Archive Computer Monitor Repair

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Computer Monitor Repair - Archived Files (cont.)

Updated March 25, 2005

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QUESTION NO. P11003-4: Samsung SynkMaster 710s monitor FCC A3LCHB770. I need the value of D630..

I believe this is a 27 Volt Zener diode, added to protect IC601.

QUESTION NO. P10903-2: Gateway ev700-7000965 monitor, picture is blurry. There is some adjustment using the focus block on the flyback, but video is still not crisp.

Check heater voltage.

QUESTION NO. P20603-8: Sony CPD-200GST monitor chassis SCC-L07B-A. I need the type and value of D608.

D608 is type RD18ESB2, an 18 Volt Zener; it is Sony part number 8-719-110-49.

QUESTION NO. P20603-1: Sony SCC-L07G-A Chassis monitor (IBM 6556-43) with Q507 (HOT) and Q520 (MOSFET "H-REG OUT") blown. No bad solder joints.

Sometimes, only Q507 and Q520 are bad, but, besides the solder, you also might check D516 (200 Volt, 3 Amp, ultrafast), D518 (10 Volt zener), D506 (damper), C508, and C575.

QUESTION NO. P20603-2: Samsung 400nb monitor. When switched on b+ line drops but rises (when lopt end disconnected) to correct value. HOT tests ok. Is lopt faulty?

This does sound like a faulty LOPT.

QUESTION NO. P20403-1: Samtron 75e /DP17LT monitor. Replaced burnt R513 and it burnt again. Checked flyback and HOT OK. Removed Hor Def yoke. Replaced R513 again and it did not burn. I did a ring test on the yoke and it hit 6., which shows acceptable. Is the yoke possibly still bad or are there other parts of the circuit I should be checking?

This is part of the G2 circuit. Check D583 , C587, R589 , R588 , R522.

QUESTION NO. P20303-4: Dell D1226H monitor CM5800 chassis has no line drive vertical line on the screen. R3544 is open, I need the value and a reason for it over-heating and going o/c.

R3544 is 1 ohm. Also check Q7532 (HOT 2SC5331), Q7543 (P-channel Mosfet MTP5P25), D6534 (Damper BY459-1500), L5526. If the semi's are leaky or shorted, R3544 can open.

QUESTION NO. P13003-4: Acerview 56c monitor (7256c). I need value of R618 (0,5 ohm ?) and cross reference of Q602. I substituted Q602 with IRF840, but after 1 day it burned the resistor and mosfet.

R618 is 0.5 Ohm, 1 Watt, fusible. Q602 is 2SK2645, a 600 Volt, 9 Amp Mosfet (IRF840 is rated for 500 Volts). Possible crosses include IRFIB6N60A or STP11NM60FP, or with insulator, IRFB9N60A or STP11NM60; IRFBC40A might squeak by, but in this unit, you may not wish to risk it. Digikey (www.digikey.com) lists the IRF FET's, and Mouser (www.mouser.com) lists the STP FET's. Since Q602 has burned, you might also check R608, R609, D605, C624, and IC601, as well. If no zener is installed at location ZD605, in parallel with R608, and if problems still persist, you might consider installing an 18 to 20 Volt zener at location ZD605 as protection for the gate of Q602.

QUESTION NO. P12703-9: Gateway 2000 Crystalscan monitor Chassis YEO711-01. Power supply makes ticking noise but will not start.

This symptom is usually due to an overload. There are many potential causes of this, in this chassis, such as shorted diodes (D311 through D315; D102, D103, D104, etc.); shorted Q105 or cracked solder on Q105; shorted Q103 or Q203; shorted C108, C104, or C105, to name some.

QUESTION NO. P123002-3: Acer AJ15,FCC AMPJ51I Monitor no display and also no power LED indicated. Replaced shorted HOT (BU2520AF) and it shorted again and confirmed FBT 751-02-56 is shorted. I cannot find the original, what is the sub for this FBT.

I think there is no sub but try http://www.electronicsic.com

QUESTION NO. P10604-9: IBM 6547 monitor, transistor KSC 5088 Blown & IRFI 6530 . I replaced them & they blew again.

If you are not able to ring the flyback, unplug and short the tube top cap to the aquadag. Now measure resistance to chassis from top cap, any reading is bad news. Can also test for capacitance, nano farad OK 15 to 25 pF bad news.

QUESTION NO. P10703-5: Proview PX-986 monitor FCC IJE 986, Horizontal deflection shrinks to about 1/3 width. Returns to full width instantly when case is flexed. No flexing will bring it back. Digital Horizontal width control adjustment doesn't affect width.

Check 22mf 250volts cap on +B rail.

QUESTION NO. P11403-9: Samsung syncmaster 450b monitor, replaced defective transistor d2125.2e with BU 508 DF then every thing ok for 120 seconds maximum and then I hear sound like caps discharge then screen vibrates and monitor powers off itself. Now the screen is white with or without data signal and the same sound problem.

I think there is a flyback spark from body to ground, that is why the set goes dead after a few seconds. Replace FBT with new one.

QUESTION NO. P11403-7: Dell 828fi, horizontal, vertical width are too wide, controls are adjusting but do not fit picture into normal, osd menu is normal. I replaced tda9109 with used one but no change, suspect flyback.

Before changing the flyback, check C509 and C517; if not these, check if IC501 is functional, and providing pulses to Q506, which drives the B+ boost FET, Q504.

QUESTION NO. P121302-3: Dell 828fi monitor 800f series was shocking. I could not find any leakages but found C5088 is bad. What replacement can I use and what is the function and composition of this transistor?

The full number is KSC5088; it is a 1500 Volt, 8 Amp, 50 Watt, Horizontal Deflection transistor. NTE 2324 is one possible replacement, as are 2SC5299, 2SC4924, 2SC5386.

QUESTION NO. P10903-3: Acer 7276e FCC JVP 7276E. Need values of burnt R241, R329 (reads approx. 10.5K ohms), and C327 these all look as if caught on fire. Also checked ZD 210 shorted off pin 1 of IC 201 a TDA 4858. Number on diode is 1N 751A a 5.1 volt 1/2 watt. I also pulled C326 another ceramic with 271 a 270 pico farad capacitor. Also should I check anything else for possible damage as most of these are in the horizontal drive circuit?

R241 = 10k, R329 = 10k, C327 = 220pF 2KV. Check R326, R328, D309, Q317 hopefully ZD201 protected IC201.

C327 = 220 pF/2KV, ceramic disk cap; use a 3KV capacitor as replacement, if possible. C326 = 270 pF/500V. R241 = 10K, R329 = 10K, R326 = 3.9K, R328 = 4.7K. Also check the 3 Amp microfuse at location J013, the small MOSFET at location Q301 (BSS89), and HOT Q302 (2SC5048). If the 5.1V zener ZD201 has shorted, sometimes IC201 is also bad.

QUESTION NO. P10803-6: I need the part number and sub for Q2001 (N1l4M K34XM) of NEC XV17+ monitor.

That marking corresponds to AN1L4M, an NEC PNP digital switching transistor. There are two series 47K resistors between its base and emitter leads, which will make this device test differently from normal transistors. The NTE/ECG 2360 is a possible sub.

QUESTION NO. P10703-10:  Optiquest Q71.  R457 was burned, I need the value.

The resistor is 680 ohm 緩 R457in circuit.

There are several different chassis used in the Optiquest Q71, but if R457 burned, yours is probably the Jean chassis, where R457 is 680 ohms, 1/2 Watt. Also replace the defective disk capacitor C449 (220pF/2KV), which caused the R457 to burn.

QUESTION NO. P10603-5: Viewsonic G810 monitor started out by making a 'snapping' sound, then going out of focus, and picture (H&V) expanding past the crt borders momentarily. Symptom was intermittent. S671 (spark gap) was the source of the snapping, and is severely discolored. The monitor finally died completely while on the test bench. I suspect the FBT, TLFA01365. H.O.T. appears to be ok.

Flyback TLFA01365 is the most common failure in this chassis, and can cause those symptoms. To obtain this flyback, try a Panasonic distributor.

QUESTION NO. P:123002-3: Samsung dp17LT monitor. Need value for R513 which is burnt.

The schematic shows R513 as 27K ohms, 1/2 Watt.

QUESTION NO. P123002-7: Acer 7176ie monitor, video output IC102 is blown, all that is legible is LM?

The schematic shows IC102 as a LM2419.

QUESTION NO. P121602-9: Nokia 447e monitor, I need the value of burned R209.

2.2 ohms

QUESTION NO. P112202-4: Mag DX1795 Monitor has very bad pincushion. Checked caps and diodes.

Try to change TDA9103 or there is a small pincushion driver transistor Q516.

QUESTION NO. P121802-6: Hyundai HT-7770C monitor. I need the values of R308 and R309, both burned to an unreadable state. R308 connects to B+ sense-input of H/V-controller TDA4854. R309 is a fusible resistor between ground and source of FET Q304 (YTA630).

R308 is 1.5K ohms, and R309 is 0.47 ohms, 1 Watt. Since R308 and R309 burned, also check/replace D310, Q304, Q310, and the TDA4854 IC.Sometimes the cause is a faulty Q310 Mosfet that has become degraded, but not completely shorted.

QUESTION NO. P121602-4: Acerview 76e monitor (7276e) powers up with black screen and LED is on green. R241, R329 and R326 were burn, I have been checking the FBT, is it usual that the pins 1&2 in the FBT are doing contact with pins 6&7? Must these pins be open between 1-2&6-7?

The Acer schematic shows the FBT 1-2 winding as being separate from the 6-7 winding; I would suspect a bad FBT. With those three resistors bad, also replace C327 (220pF/3KV), and check Q301 (BSS89) Q302 (2SC5048), ZD210 (5.1 Volt), IC201 (TDA4858), R328 (4.7K), and the 3 Amp micro-fuse at location J013.

QUESTION NO. P112502-4: I have been getting a problem with the Viewsonic monitors that seem to use more then one kind of fbt in the same model. Is there a way to help me figure out what FBT to order by chassis? Viewsonic never goes by the number on the fbt itself, and I do not have Service Manuals for all of them. I have a couple of G810 monitors but do not know what FBT to get.

Typically, the Viewsonic "VCDTS" model number will end with a suffix, like -2A, -4M, etc, whose number indicates which revision of a given model, you have. For those Viewsonics which are Panasonic chassis (not all are), you can usually find a Panasonic chassis code on the PCB board edge, like HV8SA, HV10S, HV12S, GV3, GV3D, etc. This helps determine which FBT is needed. HV8SA uses FBT# ETF42L31AZ, HV10S uses FBT# TLFA01365, HV12S uses ETF40L48AZ, GV3 uses TLFA00965, etc. Note that some models, like GV3, need Viewsonic's software, to adjust the focus after replacing.

QUESTION NO. P112202-7: Mag DX15-T monitor has excessive, out of range width. Horizontal size & pincushion adjustment from on-screen menu have little effect.

Look for open resistors of low value & a diode mounted to a heat sink standing vertically which is probably open or short.

QUESTION NO. P112602-2: Philips Brilliance 107 monitor, model 17A8808q, chassis CM8800, FCC A3KM060 no picture. Replaced defective Component 7503 BU2527A and component 3518 1R, after a few hours, a day or a week the same components are again defective. I replaced lin. coil 5508 but that is not the problem. I have three of these monitors with the same problem.

Check all the B+ line caps and any 1-2KV ceramics in the deflection circuit have found these electrolytics to lose capacity totally causing HOT to blow & sometimes other parts.

QUESTION NO. P111902-8: HP Ergo 1280 model D2840A monitor FCC IEY447S has no picture only LED blinks then fades, fuse F103 (6.3Amp/250volt) is blown and next to it D131 (FEP16 BT ) is short circuit.

Check for shorts in all power semiconductors D, T and SCR. After repair, use a 40W light bulb in series with power line, then a 60W, then a 100W, then directly connected to power line. This is to avoid burning again all the parts that you'll have changed.

QUESTION NO. P111902-7: Acer 7276e monitor starts up with fussy blue retrace lines that disappear after about an hour. I changed a couple of capacitors by the flyback and still no change.

Check on the PCB connected to the tube neck's. Here you have R, G and B colors circuit's. Identify the blue circuit and compare each capacitors that you find with the ones similar the the red or green circuits. It could also be due to a heater-cathode short. But this would normally not disappear after an hour of use. You can also temporarily switch the color output circuits. Blue to red and red to blue then see what is happening on the screen.

QUESTION NO. P112602-6: Packard Bell A926 monitor. Replaced blown FBT Bu 4525Ax and FET J512. After about a half hour it starts overheating.

Overheating is normally due to a wrong polarization of power transistor or a defective damping or clipping diode. Check for changed value or bad R, C or D around the HOT and maybe the FET that you changed.

QUESTION NO. P112502-9: Gateway EV700 monitor FCC iawe7006. I need the value of R253. I think it has the Mag Chassis.

R253 is 10 ohms, 3 Watts.

QUESTION NO. P112502-10: Sony CPD-17sf2 monitor. I need the value of zener diode D505, located near Q503.

D505 is a 10 Volt zener.

QUESTION NO. P112202-6: Gateway EV-700-069EV monitor FCC BEJC780. Looking for the values of R798 and SG702 located near the flyback. Both are burnt beyond recognition. Is this the chassis that has a high failure rate for the flyback?

R798 is 10K, 1/2 Watt; SG702 is a 300 Volt spark gap. The schematic shows that these connect to a pin of the flyback, so I'd suspect that an overvoltage from the flyback damaged them.

QUESTION NO. P112202-5: I need the value of R502 and R503 for Hyundai DeluxScan 17B+ Model HL-7870A monitor.

I show R502 as 10K, and R503 as 5.1K. These are in the ABL circuit, so probably they burned due to a faulty flyback transformer, which also would need replacing.

QUESTION NO. P111902-2: Mag 1795 monitor, need to know the value of zd301. Monitor has been shelved for a while and this component appears to have been taken off the board.

ZD301 is an 18 Volt Zener.

QUESTION NO. P44-6: Silicon Graphics (Sony) GDM-20D11 monitor goes into standby mode immediately on switch -on. Can hear HT come on, so HOT is good. Power supply OK. Power lamp steady green, standby lamp also steady amber. There is a little switch in the back enabling "Test". When doing so, screen lights up and a blurred (no sync) picture is seen. Checked/replaced all the electrolytics on the DA-board. Could it be the monitor cable? It has the label C-133-6 for SUN monitor.

First, the SGI GDM-20D11 is a sync-on-green monitor, so be sure this sync is being provided by the computer. The 13W3 pinouts for SUN and SGI are not identical; at the following webpage, www.monitorworld.com/Cables/video_standards.html#13W3SGI you can get the pinouts of these cables, to compare with your own cable.

QUESTION NO. P44-4: Sony CPD-1425 monitor totally dead and no light on LED. I replaced HOT with BU2508A. What exactly HOT for that monitor? I replaced all electrolytic caps that were short or dried. FET is ok (I think). Fuseable Resistor is Ok too.

I think the HOT is BU2520 = 10 Amp (BU2508 = 8 Amp). Check for cracks in the board, by the flyback and repair any broken connections.

QUESTION NO. P42-8: AST RM07F11 monitor FCC GWGRMO-RT07FXX with high voltage, no video. Q302, zd 301, q350, c350 are gone. I need the value of ZD 301.

ZD301 is a 15 Volt zener. With those four components blown, it is advisable to resolder the large rectifier D303; also be sure its bottom lead extends entirely through the board, or add an extension wire if it was cut too short.

QUESTION NO. P42-2: Acer 1454e monitor keeps blowing HOT BU2508AX, why?

I would ring flyback. Check caps in voltage regulator circuit for high esr. Also check the driver transistor .I would sub it instead [they do loose gain and develop leakage]. Check voltage from regulator that it is not too high by subbing ho transistor with 25 w lamp connected where collector, emitter went. monitor the voltage at collector in respect to emitter. It should not be higher than power line voltage ie 158v. Probably around 120- 130 vmax from regulator if it's working right.

It sounds like this Acer may be similar to the Acer FCC# JVP7134e chassis. There are many possible causes for repeatedly blowing HOT's, but one common cause, in that chassis, is a bad disk cap (C335 = 220pF/2KV) on the AFC line to IC201. If R214 = 15K is also bad, then IC201 itself may be damaged as well. The horiz. drive cap C319 might be bad. Bad solder joints, such as on drive transistor Q315 or drive transformer T301, or bad connections for the FBT or yoke, are also potentially damaging to the HOT.

QUESTION NO. P327-4: CTX pl5a monitor FCC DBL1454EL with no video. I replaced D109 (burned) and R717. When power applied, a rare sound noise appear, in 20 second the resistor burns again.

If R717 has burned again, be suspicious of a defective flyback transformer. Also check associated components, R712, VR702, C721, and IC701 (TL431).

QUESTION NO. P328-9: Packard-Bell 1512 SME, LiteOn monitor came in with a refresh rate of about 20 Hz and all out of sync. I replaced the IC 93C56 with 93LC56, and the TDA9102 (which did not help) and the MTV003 (did not help). Now the 130 voltage is around 90 volts, the peak voltage of the HOT is around 750 volts. I cannot find any way to restore the voltages to normal. I think that because of the low voltages the picture is still out of sync.

If this LiteOn is FCC H4ICM15006, I trust that you used a pre-programmed Eeprom (the 93C56 chip) as your replacement, and that it was the correct version for your chassis. (The 130V can get reduced to around 88-90V, with a corrupt/defective/unprogrammed Eeprom.) If the Eeprom is good, then the next suspect is a defective microprocessor (IC701); again, be sure to use the correct version. It is helpful to apply a grounded heatsink to IC701, to protect it from thermal faults or arcing.

QUESTION NO. P328-1: Princeton eo70 monitor with R901 and R902 burned, I cannot identify their value.

This Princeton is a KDS (Korea Data Systems) chassis, FCC EVOKD-1730. In which case, R901 = 27K, and R902 = 12K. If these resistors burned, it was probably caused by a defective flyback transformer (KDS FBT# KFS61411A). This flyback has been a common failure in the Princetons, and in KDS models like KDS VS-7. They can be purchased either from Princeton, or directly from KDS for the KDS chassis.

QUESTION NO. P328-7: Princeton EO17 monitor FCC EVOKD-1730 with a shorted D406 causing the cir. board to burn open between it and C437 / (jumper)R410. It also has an overheated R304. I need the cross or sub / spec for D406 and value of R304 so I can obtain them locally. Also, are any other components in that area likely to need replacement / checking?

In a KDS FCC EVOKD-1730, D406 is Shindengen's D1NL20U, a 200V, 1 Amp, Trr < 35 nsec ultrafast rectifier; NTE/ECG 587 or 574 might substitute. R304 is 4.7 ohms, 1/2 watt. Also check/replace the vertical IC (IC301).

QUESTION NO. P326-3: Packard Bell 1512SL monitor. I need the part number of the function control chip thermal. Zilog 1570. It is positioned under the CRT and also any other chips that may be problems in this area.

I assume this 1512SL is the chassis made by Lite-On (FCC# H4ICM15006), not one of the other P-B 1512SL chassis (made by Goldstar, etc.). If so, the number of this Zilog is Z0861404PSC-1570 (be sure it is version# 1570). Often, however, that Zilog, if thermal, can be made to function by attaching a (grounded) heatsink to it. The other high-failure chips in that area are I702 (MTV003N) and I703 (Eeprom, Atmel 93C56). The Eeprom is the more common failure, and must be obtained preprogrammed. Try LJ Enterprises (www.ljent.com) or Nationwide (www.neiparts.com) for these chips.

QUESTION NO. P323-9: Acer 7176ie monitor, when switched on, the power comes, led light on and relay clicking but no raster. Checked B+, it is normal. Measured the voltage across HOT, no voltage. Changed many capacitors around hot/fbt, but still symptom.

If there is no B+ to the HOT collector, is the gate of the B+ regulator FET Q303 being driven? If not, do the pair Q301 & Q346, and Q302, operate? Is the initial drive signal emanating from pin 6, of IC304 (TDA4855), or is IC304 being shut down, due to low Vcc (pin 9), or by an Xray-protect input (pin 2), or by taking HPLL2 (pin 31) low? Did those replaced capacitors include C320 (disk cap), and electrolytics C307, C353; as well as the trio C3950, C3951, C3952, and their associated 1 Mohm resistors?

QUESTION NO. P322-4: Techtronic monitor (made by Panasonic/Matsushita) pn 119-5113-00, chassis 21HV4S shuts down after a couple of hours. After shutdown it will not turn back on until it sits at least a half hour, then it will only stay on a minute or two. I was able to wake it up by plugging and unplugging the power cord a few times, but in the process of troubleshooting this way the Horizontal output transistor shorted. I replaced the transistor and the HV diode across the transistor and the original problem was back. I removed the output transistor in an attempt to test for signal on the base drive but the monitor instantly shuts down with the transistor removed. In circuit testing with DVM found no other obvious problems. I'm guessing it's the flyback (pn ETF42L28AZ) and I am in process of trying to locate one. I do not know how to troubleshoot it since it immediately shuts down (power LED off) when the problem occurs. If this sounds like a cap failure how do I find the right one, or should I just start replacing caps. (there's a bunch of them)?

Well, there are some caps known to cause shutdowns in the HV4 chassis. The worst offender is C839, but also C867, which tend to leak fluid out their bottoms onto the board underneath, corroding traces, and conducting high voltages to vulnerable components. Check underneath the caps, clean up all fluid and corrosion, repair any damaged traces and replace any damaged components. C709 & C886 are also known to cause shutdowns if bad, though they may not have leaked to do this. Also, the main board is flimsy, and can get cracks easily. It doesn't take very rough handling to get these, so any cracks may be very fine, needing magnification to see. Jumper any cracked PC runs. A marginal optocoupler PC831 may cause intermittent shutdown on occasion.

QUESTION NO. P222-7: Mag 1795 monitor has no H-drive. Daughter board has +12V feeding it, however pin 18 (VCC) of TDA9103 has only 3 volts. There is a crispy resistor in the position of J709, I need the value.

Another way to find the value of resistor in position j709 is to file a notch in the exact center of resistor burn't , measure from center to one end [the end that measures a resistance ] and multiply value measured by 2. This works in most cases.

QUESTION NO. P320-2: IBM 6555-773 monitor has overdriving G2. It is just raster no video.

Once again, the likely problem in this GDM20E03 chassis is IC420, which controls both the G2 levels and video signals.

QUESTION NO. P320-1: IBM 6555-773 monitor has no video when turned on. I adjusted the brightness button , but nothing happens. However, I can see in the dark the display for brightness is up to 100% already.

The FCC# for this IBM model indicates that it is a Sony GDM20E03 chassis, and it suffers from the same faults as that chassis (listed elsewhere on this page). The common problem is IC420 = CXA1907S (Sony p/n# 8-752-071-56). This IC controls both G2 and RGB video. If pin#22 of IC420 is too low, G2 voltage will be too low. If the fault is low or no filament voltage, check C677 and C683.

QUESTION NO. P37-1: Proview 770 monitor died. No power, no lights, nothing. Fuse is good, cleaned brown glue from flyback area. Has about 150vac on primary of T501 and nothing on secondary. Is this likely the only problem? I need to identify T501 and a source to buy one. Number on Transformer are 730-102-7721 9928 LAE.

For this type of component, contact Proview; they will sell parts, but have a minimum. EMC/Proview, 800-776-8439, X5712, Reggie Rosca, parts dept. Have on hand all relevant information, model#, serial#, date of manufacture, part location and marking, etc.

QUESTION NO. P316-4: Compaq V55 612 monitor is dead, the led does not light. Replaced Q402, still does not work.

The flyback transformer, and IC602, a Samsung KA2S0680 (in the power supply), are known failure components.

QUESTION NO. P36-4: HP d2807a monitor, I need the values of R335 and R601.

I believe this HP is similar to a Viewsonic 17G (Panasonic chassis). In the Viewsonic, R335 = 2.2K, and R601 = 150 ohm/2W. You might check Q305 = 2SA1872.

QUESTION NO. P39-9: Princeton Ultra monitor, had 1" horizontal band in the middle of the screen). Checked and replaced Bu2525af--problem solved. Then after couple of days it would not turn on (led turning on on front panel but dead.) Checked both HOTS and saw that a mosfet in the switching power supply had gone bad but I do not have any part # (k21--). Tried a k2142 but mosfet shorts and has been blowing fuses ever since. Also replaced 3842.

If this Princeton "Ultra" is an Ultra 17+, and if the FET is Q801, then it is a 2SK2141. The 2SK2141 is rated for 600 Volts, while 2SK2142 is only a 250 Volt FET. Also, you might check ZD801 = 12 Volt zener, Q414, & Q416. However, I do not know if this information also pertains to the Princeton Ultra 14, Ultra 15, Ultra 20, Ultra 70, Ultra 75, Ultra 100, etc., if your chassis is one of those, instead.

QUESTION NO. P39-8: Dell D2026ths monitor (crosses to Sony GDM20e03), has no video and no high voltage. The tube does not light up at all but the green light stays on and has good power draw. I had the monitor working once, was letting bench test picture started to flicker then went out. I have not been able to get the video back since.

Try checking for any cracked connections around the flyback on the G board. Also might check C677, C683, and IC603 while there.

QUESTION NO. P39-5: ADI Microscan 5PD monitor, I need a sub for a shorted HOT, part number 2SC5515 made by Panasonic.

2SC5515 is rated 1500V, 17 Amp Ic (27 peak), 65 Watts, Vce[sat] <3V @ 8.5 Amps Ic, Tfall < 0.2 usec. Possible subs for that could be 2SC4891, 2SC5045, and 2SC5411. (Relative to other manufacturers, Panasonic tends to define their maximum currents more generously, given that they test Vce[sat] and DC gain well below that maximum.)

QUESTION NO. P39-4: Princeton monitor FCC Kdsevokd-1730. Changed flyback and Q411 (with originals from Kds), R901, 902, 904. The monitor came on for a few seconds, then the flyback began to squeal and blew Q411 again. The voltages from the power supply are correct.

Since R904 was one of the burnt resistors, IC401 (TDA9103 or STV7778) may also have been damaged by the fault, so check that IC. Also, it is not unheard of, for KDS to provide a replacement flyback for EVOKD-1730, that is defective right out of the box! Other items to check might include Q405, Q407, Q408, Q415, Q416; C437, C438, C447; and IC402. The Princetons also can get bad solder on W404 (also on the FBT, but probably not an issue anymore), and bad yoke connector connections.

QUESTION NO. P39-2: Sun/Sony GDM-20E20 monitor lacks vertical linearity (showing a "S" wave form from top to bottom). Cannot be adjusted on the front panel. The symptom remains stable for every resolution. According to the answers to the Q. P1019-7 & P930-1, I replaced all elect. caps on the DA board, and got no improvement.

The GDM-20E20 is not the same chassis as a GDM-20D10. One common failure in the GDM-20E20, that gives linearity & other problems, has been IC007 = CXA1908S, the DPU on the D board (Sony p/n# 8-752-076-34). This IC is expensive; I'd try to confirm the cause with a board swap from a working unit, before buying it.

QUESTION NO. P39-1: Dell Ultrascan D1626HT monitor shows no signs of life at power-up. The fuse is good and I can trace 120 back to the large rectifier. Even the degauss relay does not pull in during power up.

The SMPS circuit in this chassis is pretty complex. The controller IC used for driving the switching transistor converts feedback for both voltage and current into a real-time power usage factor, via an onboard multiplier function. I suggest getting the service manual (Sony p/n# 9-978-596-02) from Sony, for the related chassis Sony GDM-5001PT, before trying to troubleshoot this Dell's power supply.

QUESTION NO. P37-9: Sun gdm-20e20 (oem by Sony) monitor, I can only see osd picture, but it is very dim (bright and contrast to max).

Is your G2 voltage too low, or is G1 too negative, or is the filament voltage too low? If the problem is low G2 (or G1), the usual problem is a defective IC420 = CXA1907S (Sony p/n# 8-752-071-56), on the CRT board. If the output on pin# 22 is too low (well below 3.4V), this will cause low G2. Be careful to avoid damaging the board, when removing this IC; it is safest to clip all the pins and desolder them individually. If the problem is not the IC420, then check IC407, and then Q403, Q414, and Q417. If the problem is low filament voltage, go to the G board and check/replace C677 & C683, and also check the solder on IC603. If this chassis was handled roughly, there may be cracks on the G board near the flyback, often at the mounting screws, which should be repaired.

QUESTION NO. P37-3: Viewsonic P815-1M monitor comes on but there is no high voltage, the output transistor for the high voltage transformer runs warm. The flyback tested good with the tester.

Check Q861 (11N008) on high voltage board. If it is open, replace it and replace the FBT (TLFA00965). The problem you will encounter is that to adj the focus, you need a special software (provided only to authorized service centers) to do this.

QUESTION NO. P36-8: Daytek DT-1536D monitor keeps blowing the HOT transistor after 20 min from applying power. There is a snap then no screen. All pins of the HOT are shorted.

These Dayteks are known for bad solder on the board. Remove the board and check all over for bad solder. Often, there is bad solder on the connections to the flyback transformer, and that can blow the HOT, so be sure to re-solder those connections. Also check D410, a dual damper/modulation rectifier.

QUESTION NO. P36-1: Sony GDM-20E01T monitor goes into (fault) shutdown within seconds after switching on. The green power LED lights as usual, and then the green and orange LED (standby) slash in sync. The right control panel LED (CENT) is then lit constantly. The HV is there, and the vertical oscillator is working, too (for about a second). Smoke has been reported to come out of the front of the monitor when the fault occurred, but I cannot find traces of it on the board. Even though it should be rather obvious because the oscillators do work, I measured the HOT and the usual suspects, everything seems ok. Any ideas what the meaning of the CENT LED is in this situation, or where to look further?

The CENT LED on solid, with the other two flashing, indicates a scan circuitry failure (usually horizontal, but sometimes vertical). One cause can be bad caps in the power supply, like C610, C611, C612, C615, C616, C617, C619, C625. Also, check Q511, Q512, D504, PS500 & PS501 on the main board. Bad solder, in either the horizontal or vertical circuits, can also cause this fault code.

QUESTION NO. Tatung c7bzr monitor with a wide screen and severely pincushioned.

This is a common fault on this monitor. Replace D434 diode pack which contains the damper and modulation diodes. Goes leaky reverse direction. Will be a DMV-32 but replace with DMV-56.

QUESTION NO. P12-10: Mag DX1795E monitor picture is too wide about 100% and adjusting picture width has no effect. Picture height is ok and is possible to adjust. I found also burned resistor, R503 and I need value of that. Degaussing has no effect.

I found a similar scheme (Mag DX17FE) where R503 is 47 1/4W and one terminal is to ABL (White) and another to diode D501 (1N4148) both in emitter of Q503 (A733).

QUESTION NO. P26-9: KDS VS-19sn monitor. I need the ID of R497.

R497 = 1 ohm fusible. I'd also check out R498, Q407, Q425, D403, D409-D412, D431, and if any are leaky/bad, I would also be suspicious of the flyback transformer.

QUESTION NO. P25-8: Apple 1710 monitor seems that something is missing on this monitor. Two pins, HP8 and HP9, are on the main board. There is nothing connected to them although I believe there should. I think that I could get the set going by placing a bridge over them but...What is the value of resistance RL115 also on the main board?

First, be sure the unit is provided separate H & V sync signals (not composite sync), or a good signal from a PowerMac, or it will not power up. HP8 & HP9 are not meant to be bridged during normal usage. However, you can try bridging HP8 & HP9 for testing IF the unit has no power LED or other sign of life (degauss, etc). You'd get degauss, etc, but not video, because it's bypassing the CPU. If this bridging works, either the solid-state relay is bad, or the CPU did not give it a turn-on signal. RL115 = 27K ohm.

QUESTION NO. P15-8: EMC SA-770 monitor is dead, main fuse ok, HOT appears ok. It blew the top of c635 (22mfd/250v).

If C635 blew, check/replace D632 (ultrafast type, 31DF4 or similar) and FET Q630 (IRF634A or similar). Also check the solder on the three resistors, off the FET source.

EMC is now recommending a chassis modification, to reduce the value of C635 to 10 uF/250V (from 22 uF). Apparently, the original value of C635 was excessive, and overstressed the circuit, causing the failure of the rectifier, cap, and FET. Also, D632 is now recommended to be outright replaced, regardless of how it checks, when C635 has failed; the rectifier can be damaged, yet still test fine on a DMM.

QUESTION NO. P110-8: Likom Technology LTM1502L monitor, I need the value of C112 which was burned and equivalent for Q101-2SK1507.

This monitor equivalent with monitor SAM M152PNLD. C112-100uF/16 and must check Q101-2SK1507 (no equivalent), U101-KA3842, R122-0,33ohm/2W, R123-150ohm, R117-47ohm, R118-10Kohm, R120-47ohm, R121-67ohm and D109-1N4148.

QUESTION NO. Nokia 447X monitor. I need a replacement part number for M3 a driver transformer in the deflection. Number on the transformer is FM2525 5373.

The part number on the small transformer IS the part number. I had the same thing on a FUJITSU-ICL monitor (even SALORA). Try all these brands (monitor may be called 447*).

QUESTION NO. Acer 7076 N monitor starts for a second, the high voltage is passing 30K-volts, and it shuts down. The VARA and VARB from the power-unit is too high, VARA is about 160V dc. I cannot find any defective components in this part of the power unit.

The circuitry design will drive the VAR voltages too high when there are interruptions in the HV or horizontal circuits, and when VREF is incorrect or missing. Check that VREF stays at about 2.5 VDC. Check for bad solder all along the VREF line, and elsewhere; esp. check/reflow the solder on the M605 connector, it is often cracked, and also the yoke connector. For the fault of excess HV, check out IC308 and IC309, as well as any diodes connecting to their pins, and check Q323, R239, and R243.

QUESTION NO. P21-7: Mag DX1795 monitor has no horizontal drive to HOT. Suspect IC 701. Is this the TDA9103 IC I saw mentioned on an earlier post? I cannot tell what the chip number is due to a ground foil glued to the chip.

Yes, IC701 is TDA9103; for confirmation, a TDA9103 is a 42-PSDIP IC package. That metal shield was presumably added for some protection against damage from arcing, which has been suspected to be a failure mode for these IC's. This suspicion is lent some weight by the observation that ST Micro has incorporated an internal metal shield into the design of their STV7778S chip, the latest generation in this series of IC's.

QUESTION NO. P131-5: Gateway 2000 monitor, EV900, Model X19001, No FCC ID has OSD but no video. I replaced the video processor (M52737SP) and the DA converter (IC403, UPD6211CX). If I apply 5V at contrast pin 17 of video processor or pin 5 of the DA converter video comes on and looks good.

Since you still get a good OSD on the display, it is likely that some parameter like sub-brightness, etc., got set too low in Factory Mode. To enter Factory Mode, power up while holding in the selector button on the display. You should now see an "F" on the OSD, to indicate Factory Mode. Check & adjust the parameters, as required.

QUESTION NO. P130-6: Nec Multisync XE15 monitor. I need the value or any information of transistor J306.

"J306" is 2SJ306, a P-channel MOSFET, rated at 250 Volts, 3 Amps, 25 Watts, Rds[on] < 2 ohms. There are not many substitutes, due to the 250V rating; the possibilities include 2SJ306 itself, 2SJ307, 2SJ449, and IRFI9634. Try Dalbani (www.dalbani.com), MCM Electronics (www.mcmelectronics.com), LJ Enterprises (www.ljent.com), or B&D Enterprises (www.bdent.com) for these devices.

QUESTION NO. P112-8: NEC multisync 70 monitor will intermittently not turn on from cold start. The led is amber and there is a constant clicking.

I just fixed one of these - it sure felt like X-ray protect but is apparently a power supply issue. Adjust the SMPS output setting, you will probably find that it has drifted out of spec (there is a pot for the adjustment).

QUESTION NO. P126-10: Magitronic C-SV1700PS monitor, the HOT shorted, also diode D407 (to-220/ 2 lead). I replaced HOT with an ECG 2365 and the diode with a NTE 598 ( I am not sure if these are the correct replacement, since I cannot read the numbers and letters on the original parts). The unit's switching power supply looks to work ok. When turned on, there was a "rattling" sound then stopped, HOT is fine but D407 shorted. Also, what is D407 for?

D407 is DD54RC, a damper diode made by Sanyo, rated 1500 Volts, 5 Amps, Trr <1.5 usec, TO220FI case. B&D Enterprises (www.bdent.com) or LJ (www.ljent.com) may have this one, or an alternative, such as Sanken's FMP-G2FS, and Toshiba's 5THZ47 or 5TUZ47, to name a few. Since NTE 598 is only rated 600 Volts, that is probably why it shorted. The ECG 2365 is not too bad a match for the OEM HOT, but you might also check if all these components shorting, has damaged the in-line microfuse.

QUESTION NO. P122-3: Impression Vienna 17 DX1795E monitor, FCC IAWDX17FG. The brightness was too high with retrace lines visible. I checked the HV and made a few adjustments, the brightness came down, the retrace lines disappeared, but the picture was green and fuzzy. Adjusting the focus improved it somewhat, but before I could check anything else the HOT blew. Does this Mag made unit need the upgrade parts changed, as listed for the regular Mag 1795? (All the part numbers on the CB are different). I suspect the FBT (focus circuit) is bad. Will the FBT for the 1795 replace this one?

Your DX1795e and the Mag DX1795 are both FCC# IAWDX17FG, and should have equivalent components. I think you may be confusing components in the Mag DX17F chassis, which has different circuit components (including the FBT), and also has a host of components that need checking/replacing when it goes down, with those for your DX17FG chassis. Before replacing the flyback, you first might check that the problem is not an internal leakpath within the CRT; for example, a focus-G2 short. The flyback# for the DX17FG is TF2-6V0-001-LA, if the FBT is the problem after all.

QUESTION NO. P119-10: Sony CPD-300SFT monitor, the power to C4833 and R638 burn. Found the power part number VDR687 may be bad. It looks like a capacitor (10V431K and TNR printed on it) but it is not a capacitor. What is it?

TNR-10V431K is a Metal Oxide Varistor (MOV), from UCC or Marcon. It is rated for 275 VAC(rms) continuous, 350 VDC; and surge of 3500/2500 Amps. It should read open-circuit (good or bad) at low voltages, and can only be reliably tested with a current-limited high voltage (1 mA, at 430 Volts +/-10%V). The Panasonic MOV, ERZ-V10D431, is an equivalent, listed by Digikey (www.digikey.com), cat# P7257-ND. Also similar, are MOV's from Mouser (www.mouser.com), 570-V275LA20A (Harris) or 1492-275V14 (Xicon); and from NTE (www.nteinc.com), their MOV's 2V275 or 2V300.

QUESTION NO. P117-10: Polycat monitor of a pick and place, the input automatically switches between the built in 386 computer and ccd camera connected to the loading arm of the machine. The monitor is not turning on. It is a European kit using stv2102, tda8174 ic. Where can I find datasheet of stv2102 or stv2102b (ic was replaced but in vain)?

Go to www.bdent.com/schematics/STV2102.pdf to get the datasheet for STV2102.

QUESTION NO. P117-9: Princeton KD-1511 monitor FCC EVOKD-1511. D806, D816 burned (marked 31DF 6 8L). Could not cross, guessed and replaced w/ generic 3amp/1000PIV rectifiers. HOT shorted. Replaced HOT. When plugged in, power led flashes, D806, 816 get very hot (desolder themselves).

If your "generic" diode substitutes were not ultrafast types, using them to replace ultrafasts like 31FD6 can result in their dissipating excess heat, or even a failure to rectify at all. The 31DF6 rectifiers are ultrafast rectifiers from Nihon Inter, rated 600 Volt, 3 Amp, Trr < 50 nanoseconds. Possible substitutes include Sanken's RL4A, Mospec's SF38, Shindengen's S3L60, Motorola/ON Semi's MUR460, ST Micro's MDV04-600, and Philips' BYV28-600. You can try B&D Enterprises (www.bdent.com) for MUR460, RL4A, and S3L60. Although "HER" type rectifiers frequently do not perform as well as the above types, if nothing else is available, then HER306 might be tried.

QUESTION NO. P117-3: Mitsubishi Diamond Pro 17 TX monitor only has green signal, even on On Screen Display. Using the correct cable. Customer says that originally, only the blue signal was bad and red has gone only recently.

The common cause of color loss is a bad SMD IC, IC201 = AN93B04SCR, a 28-pin flatpack IC on the back of the video board, p/n# CP263P05701. However, due to the expense, check first for loss of color signals occurring at that IC. If IC201 is not the problem, loss of colors can also be caused by bad solder joints along the video path, and sometimes by a failure of IC203 = LH2426S, the video amp, on a heat sink.

QUESTION NO. P112-7: Sony CPD-100GS monitor. Shorted D516 and Q520 IRFI9620G, after replacing with new parts, monitor would turn on with signal cable disconnected, OSD came on but the same parts would short immediately when signal cable is connected to computer.

You might check Q507 & D506 for excess leakiness/short, and see if the solder on the leads is cracked. Also, if the D516 (typ. a Toshiba 3DL41A) was poorly subbed, both D516 & Q520 would blow again. NTE/ECG 588 can be an acceptable sub for 3DL41A, if the original rectifier is not obtainable.

QUESTION NO. P111-5: PC Direct /Smile CA6736SS monitor FCC GBVCA6736SS came in with a shorted red drive. I replaced that and it worked well for a couple of days. Then the chopper transistor in the Power supply blew. The fuse went as well. I replaced the main power supply FET with a 2SK2161. I am not sure of the original as it was blown apart. It seemed to read 2sk214? I also replaced the PWM chip UC3842 and of course the fuse. When powered up again the fuse and trany went. I tested all secondary diodes the HOT, pre driver, all caps and diodes in the powers supply primary, in fact everything in the primary even the main power transformer. All test OK. The unit does not use a PTC which can crack and cause such a fault. All other posts only discuss horizontal faults in these monitors. I have checked all the remarked components anyway.

A 200 Volt FET (like 2SK2161 is) seems a pretty low voltage rating, to use as a replacement for a chopper FET in the primary of a SMPS. If the original FET began with 2SK214x, and had a TO220F case (like 2SK2161), the best candidate for the original FET is probably 2SK2141, rated at 600 Volts and 6 Amps; B&D and MCM's catalogs list 2SK2141. Or you could try an NTE/ECG 2379 (or an IRFBC40) with insulation hardware. Some known failure components in this chassis include D104, D105, Q103, Q105, and R111.

QUESTION NO. P15-1: Samsung SyncMaster 3Ne monitor, the screen is only showing half of the video, and is folded over on top. There is also a very bright white line in the middle of the screen. I checked the RGB cable from the video card to the CDU with a multimeter but it is intact.

Vertical output IC needs replaced, and then check caps.

QUESTION NO. P19-1: Daewoo CMC-1707B monitor. I need a source for a transistor type No FMP-3FU in the UK.

FMP-3FU is not a transistor, it is a dual modulation/damper rectifier, made by Sanken (Allegro). You might inquire from Sanken's UK distributors, listed at http//www.allegromicro.com/salesloc/sal1eur.htm. Also, B&D Enterprises (www.bdent.com), in the US, does ship internationally.

QUESTION NO. P14-6: Micron 700CX monitor stopped retaining digital screen settings after power has been turned off. Once the power has been turned off and turned on again, the user has to readjust the size and position settings, etc. (using the front panel buttons).

Replace the Eeprom on the main board (an 8-pin chip with the number something like 24lc16b). This is the same Eeprom that holds all of the alignment settings also so you will have to reprogram a new one by downloading the stored data in your existing Eeprom to an Eeprom burner and then burn a new Eeprom. Otherwise you will need to get one off of another Micron main board.

QUESTION NO P19-3: Sony (Silicon Graphics) GDM20E21 monitor has a display that appears that the bottom 1/2 of the screen is compressed to 2/3 normal size on one trace then on the next trace the screen appears to be too large. Straight vertical lines seem to also be jagged or skewed left and right. The problem is isolated to the board on the left side of the monitor as you are facing the screen (The board containing the HOT and other video amplifiers.)

I would be suspicious of IC007, the DPU IC on the D board. It is common for this IC to fail, and create deflection problems like these, and sometimes even shutdowns.

QUESTION NO. P19-2: Sony (Silicon Graphics) GDM20E21 monitor has a dim display.

This chassis is related to the Sony 20E03 chassis, and shares some of the same problems. If the problem is bad voltage on the CRT filaments, try checking C677, C683, and IC603, on the 'G' (power supply) Board. If the problem is reduced G2 voltage, or low G1, try checking IC420 = CXA1907S, Sony p/n# 8-752-071-56, on the 'A' (CRT) Board. If the voltage from pin#22 (typ.~3.4V) of IC420 is too low, the G2 voltage be too low.

QUESTION NO. P18-6: HP D2818A monitor manufactured 1996. According to your answer some time ago, this monitor had a weak CRT made by Samsung. Can I swap the HP CRT (M41KUK36x01) with an Apple CRT (M41KKA16x)?

I am dubious of such a substitution. That Samsung CRT is a shadow-mask type, while M41KKA16X is a Sony Trinitron (aperture-grille) type, and has three separate G1 pins, one for each cathode (R/G/B). I would lean towards using a Hitachi CRT/yoke assembly for a replacement. So long as the horizontal and vertical coils have similar inductances to the coils on the Samsung CRT, replacing the entire CRT/yoke assembly will make one's life much easier, in getting acceptable convergence, compared to trying to swap the Samsung's yoke assembly onto a replacement tube.

QUESTION NO. P18-5: AT&T CM1200 monitor FCC A3KM055 (Philips) went to excessive width, which cannot be adjusted with screen controls, pincushion also has no effect. The video is otherwise OK. There are no signs of burnt components or overheated area's of the board.

Try checking the ultrafast rectifier at location 6614, typically a MDV04-600 (could substitute MUR460 or NTE/ECG619), for excess reverse leakage or shorts.

QUESTION NO. P15-6: Apple Multiple-scan nr m4436 monitor with 1705 display, the horizontal adjustment and width (horizontal) pinoculation cannot be adjusted. The vertical adjustment is okay, the whole adjustment is being done by the same console. (no pot meters).

The usual problem is either a defective Q405, or bad solder on Q405, sometimes also causing R448 (390 ohm), located across B-E of Q405, to burn as well. Occasionally, the programmed Eeprom (a 93C46 or similar chip) needs reprogramming/replacing.

QUESTION NO. P1226-9: KDS' Multi-Scan Color Monitor FCC IDEVOKD-1730. The fuse had blown and the connector H403 had burned. The following components were faulty: Q801 - K2333, Q411 - BU2525AF, Q407 - C4368, Q415, Q416 - IRF630, IRF644, IC801 - UC3842, D812 IN4148. I replaced all the components, mostly with equivalents. On switching the monitor on, the fuse is blown. I hope this monitor does not have that KDS design flaw that requires an upgrade. I suspect that the flyback is the cause but I'm not sure and don't know the replacement part number. Also is seems very hard to remove the CRT-base board - how is this achieved (might be glued on)?

The flyback is KFS-61411A, and can be obtained directly from KDS. This chassis is not the one requiring the upgrade; the upgrade is for FCC# EVOKD-1700V.

QUESTION NO. P1227-3: Viewsonic 17 monitor chassis 1782-2 has no vertical height (just displays a line). Is this likely to be the vertical IC? If so, where is the IC located, and should any other components be replaced along with it?

Has this unit been worked on before? If it is a relatively clean unit, check the Connector and Wiring from the Vertical circuit to the Main Yoke. Sometimes at the factory they seat the connector poorly, or do bad crimp jobs.

I believe the vertical IC is IC490, LA7838. You might check it for internal shorts, or for faulty power rails (pins 1, 8, 13); also check for bad solder, and check resistor R499 (1 ohm).

QUESTION NO. P1227-7: Viewsonic 17EA monitor, power LED blinks on then goes off when power is applied. R76 is burned. Nearby transistor Q10 is shorted. Power stays on after removal of Q10 (D1563A). What is the correct value of R76?

The value for R76 is 100 Ohm .25 watt, the color is Brown, Black, Brown, Gold.

QUESTION NO. P1227-4: Digital VRC21-HA monitor. I need the replacement part number for Q341.

Q341is a chip transistor labeled in the schematics as C3338. It is in the BLUE predriver on the video board. The parts list lists Q341 as 2SC3338AR02. The monitor is manufactured for DEC by Mitsubishi. The Mitsubishi model is a THZ8165SKTKW-AE.

QUESTION NO. P1219-8a: Samsung GLsi monitor has lost horizontal scan, the image is squished to 2 inches at the center.

Try checking for a leaky Horizontal Output transistor (MJW16212).

QUESTION NO. P1222-3: CTX VL500 monitor loses Horiz and blanks out if the case is pushed on but is restored when pressure is removed from the case. Removing the case, it is almost impossible to re-create the problem. I found some cracks in the PCB but after fixing these cracks and jumpering all associated tracers, the problem still persists. If the deflection board is bent extremely, it will blank out. I magnified, poked, bent, just about everything and I cannot find it.

Try checking/reflowing the solder off the legs of Q106.

QUESTION NO. P1218-5: Sun GDM-20E20 monitor is too bright, only can see some line on screen. The G2 voltage is 0v, KG\KR\KB voltage all are 10v.

Try checking IC420 and IC405.

QUESTION NO. P121-9: IBM 8513001 monitor. I need values for R806.

Iif R806 is from the power supply then its value is 370 ohms at .25watts.

QUESTION NO. P1211-8: KTX BM15D monitor is missing the plug. The DB-15 pinout for the ground is red, green, blue, red ground, green ground, blue ground. The wire has a grey shielded wire (green, green ground), a red (red, red ground), a blue (blue, blue ground), all those wire are shielded (ground). I have to find ID bit1, ID bit2, ID bit3, Vsync, Hsync. The orther wires I have are black, white, yellow, orange and brown. (not shielded.)

pin 1 red (video), pin 2 grey (video), pin 3 blue (video), pin 4 black (matt), pin 5 black (matt), pin 6 black (video red), pin 7 black (video grey), pin 8 black (video blue), pin 9 n/c, pin 10 black (gloss), pin 11 black (matt), pin 12 brown, pin 13 white, pin 14 yellow, pin 15 orange.

QUESTION NO. P1226-2: Gateway EV700 (YE0711-01) monitor has a blank screen. HV is ok. Problem started intermittantly. Pilot light seems to work ok, even in power savings mode, but screen is now always blank. HOT checked ok. Tried solder reflow of various sections with no luck.

Check voltages off the SMPS. If low try replacing caps like C922 1000mf@16V.

QUESTION NO. P1214-2: Apple M1823 monitor. In reference to questions NO.P817-4, NO.P628-3, and NO.P922-7, I have three M1823 units with identical problems: flashing LED's (power saving and center light on left side of monitor) and no video. The following refers to one of the three units I was able to locate and test all picofuses, R851, R868, D824, and D825. All tested ok. I removed Q512 and tested its hFE with a RMS DMM which shows its value to be 4.85. I am unsure as to the nominal specification of this (hopefully bipolar) transistor because the number printed on its case (C3997 4B4) does not come up in any searches I have done. I also removed Q511 (P-MOSFET # IRFI9630G), but have been unable to verify if it is good or bad as my RMS meter does not handle FET type transistors and I do not know what values to read on which pin during an in-circuit live test. Will a bias test (treating the transistor as if it were two diodes) work on FET's out of circuit? The capacitors C611 and C612 on the power supply physically look ok, but I am unable to read their high capacitance (3300 microFarad) values directly with my limited meter. You also mention checking electrolytic caps for bad ESR leakage. Can that be performed with a standard DMM? My assumption is that the fault is in the horizontal scan circuitry (perhaps Q511 primarily), but I am unsure. I am fairly new to the component level repair of monitors (I used to just board swap) so I appreciate your patience with my novice questions.

First, in using those other answers, you must distinguish between the "central" LED of the five closely-grouped Adjustment Indicator LED's (that LED is actually for Pincushion/Geometry), and the Centering-Adjustment indicator LED (the rightmost of the five indicator LED's). Q512 is a 2SC3997, a Sanyo NPN transistor (pinout BCE), the case markings show only the base number. To test a Power MOSFET with a DMM, first check that there is very high-to-infinite resistance (out-of-circuit) between the gate lead, and either drain or source leads. Then short the gate to the source, and check that there is a good diode junction between drain and source (infinite in one direction, one diode-drop voltage in the reverse direction). This diode will be forward-biased from drain to source on a P-channel FET (like Q511, pinout GDS), and the reverse direction on an N-channel FET. As most FET's fail shorted, this usually is enough. Rarely, a FET fails as nonresponsive to its gate applying a voltage roughly 10VDC (9-volt battery is OK) between gate and source (Source more positive on a P-FET, more negative on an N-FET), will cause the drain-to-source resistance to drop from infinity, to a low value, on a good FET. Testing electrolytic caps for ESR with a DMM can only be done in a cumbersome manner, and only if the DMM has a frequency-response for VAC, that is accurate up to about 10 KHz or higher. If your meter does have that capability, you place a small (1 to 10 ohm) resistor in series with the cap leads, apply a 10 KHz sinewave signal across both, and use the meter to determine the value of the AC voltage which is dropped across that resistor, and then across the capacitor. By assuming the voltage dropped across the capacitor is due to its equivalent-series resistance (ESR), you find the ESR from the formula ESR = (Cap.voltage/Resistor Voltage)•Resistor value. However, good ESR meters are MUCH easier to use, and quite inexpensive, well worth the investment (Anatek, for example, sells the Dick Smith and Cap-Wizard meters, both fine ESR testers).

QUESTION NO. P1212-9: Applevision 1710AV monitor, I need the values for two burnt resistors RL48 and RL52.

RL48 = 470 ohm, and RL52 = 2.7K ohm.

QUESTION NO. P1213-9: Sony GDM-20E03 monitor takes 15-30 minutes to get a picture on the crt. The high voltage is coming up as soon as the monitor is turned on. Also, there is no glow in the tube while there is not a image and the led is solid green. The input has been verified to be good.

The most likely cause would be two marginal or leaky capacitors, C677 = 100uF/25V and C683 = 1000 uF/16V, on the power supply board ("G" board). While there, check for any cracks on the G board that may need jumpering, especially by the FBT, around the two support screws. If there is still a problem, try checking out IC603, and its solder.

QUESTION NO. P1212-1: Mag dx17f monitor. Green light on, no picture, no secondary voltage out of the power supply. Replaced c321, c301, zener diode off r305 mounted on the back of pc board. Voltage on ic 304 is pin 1-0.9volts, pin 2-minus 0.17volts, pin 3-0, pin 4-minus 0.6volts, pin 6-minus 137volts. Q301 measures not shorted. Flyback transistor, q109 is ok.

Is IC304 is functioning, and doubling your 137V across the two big filter caps? If not, check resistors & caps around IC304, check IC304 itself, and diodes D301 through D304. If the voltage is doubled, is there voltage reaching the drain of Q301? If not, check for bad connections, or a bad primary winding, on the transformer. If there is good voltage to the drain of Q301, is R311 good, and is IC301 delivering good pulses to the gate of Q301? If good pulses are reaching Q301's gate, but it is not turning on, perhaps the FET is nonfunctional. If no gate pulses at all, is IC301 getting good start-up and running voltages to pin#7? If insufficient (<16V) startup voltage, check the two 360K tickle resistors. If these are OK, check that IC301's running voltage stays good, & check IC301 itself, and the components around it.

QUESTION NO. P1127-7: CTX 1765CD monitor has only a white/color vertical line in the center of the screen. The hor. deflection should read 58V, but it is 0v. At T304 58v is also missing. Q314 looks ok, as well as D319. I think those should provide that voltage. Q319 measures 0 0 4 V, where I would expect 58, 180, 61V, on T302 and T304 the 58v are also missing.

Besides the Q314, D319, and Q319, try checking D420 and R380.

QUESTION NO. P128-5: Gateway CPD15F13 monitor FCC AK8CPD15SF1 - 1994. The unit shuts down after a certain length of time. Is this because of the keyboard and mouse are not installed? Also the color of the screen is light blue when the brightness is turned up. No adjustments on the crt to set the gray scale.

What you need is a video signal with good H and V sync inputs, to keep this chassis from entering power-save mode, not specifically keyboard/mouse. This chassis is notorious for bad solder and cracks in the main board. Check carefully for cracks, with magnification, and jumper any broken PC traces. Check for bad solder everywhere, but especially in the front center area of the board, and around IC502 & IC504, also the rivets on the heatsink around the flyback, on the horizontal drive transformer, and the HOT & other big transistors. Another cause of shutdown after several minutes is sometimes from overheating of a daughterboard at the front. Regarding the color balance, on this model, it is adjusted by Sony's DAS software program and interface, using the 4-pin in-line header on the main board.

QUESTION NO. P128-7: Viewmaster CA1706 monitor. Both Horz O/P and EHT generator are ok and pulse levels seems ok as well on both base and collectors but I have no EHT whatsoever.

Check c510 & c511. If that does not work, try replacing lcd.

Replace C117 electrolytic capacitor (adjacent to Horz O/P Transformer) it dries up or goes open circuit.

QUESTION NO. P125-1: Proview PV-7221M monitor had ticking sound. I replaced HOT C5150, worked for 24 hours then dead again and HOT shorted out.

2SC5207A or 2SC5251 are probably better choices for Q615, than 2SC5150, for this 17" Proview, but that change may not solve the immediate problem. Try checking/replacing the solder on the horizontal/vertical yoke connector. Also a good idea to resolder generally, but perhaps focus on the area around IC604. Probably also should replace C629, and check that FET Q621 hasn't gone bad in the interim.

QUESTION NO. P1130-4: Acer 7278c monitor has bad pincussion and is narrow.

BSS89-DMOSFET (Case T0-92) location Q301-9 or around flyback outside the heatsink. Have used IRF630 MOSFET, but not quite the screen size, as the original part.

QUESTION NO. P121-8: Sony GDM-20E21 monitor has flyback lines on screen. There is no G2, because the signal from pin 22 of a CXA1907S is low, which is shutting of the G2. I have a +ve 7volts on each of the G1's, and there is no drive on any of the cathodes. Is the Video Pre Amp common to cause this fault ( CXA1907S ). My clamp pulse is sitting on a 0.5v DC level, and the amplitude of the clamp pulses are 6 volts. I am not sure if this is correct.

A defective CXA1907S (Sony p/n# 8-752-071-56) is a common cause of problems with G1 and G2, often resulting in little or no G2 voltage. Besides the video preamp circuitry, CXA1907S contains DAC circuitry, for setting the levels of RGB bias & gain, contrast, G1 & G2 voltage. So it is conceivable it is causing your symptoms. Note that the video output IC, IC405, is also a known failure component in these chassis.

It could be a blown fuse PS001 on the videoboard. Sometimes it blows without any reason.

QUESTION NO. P1121-1: Digiview HR-50 monitor, d703 is shorted (by359x) has no cross. Where can I find this part and is there anything else that needs to be checked?

BY359X-1500 and BY359X-1500S are Philips dampers, rated for 1500 Volts and 10 Amps, in an insulated TO220 case. The 'S' version has a faster reverse recovery time. A regular BY359 might substitute if insulating hardware is added. It may also be possible to substitute Sanken's FMQ-G2FS or FMQ-G2FLS for BY359X; both are 1500V, 10 Amp, in insulated TO220 cases; FMQ-G2FS has the faster reverse-recovery time. B&D Enterprises (www.bdent.com) lists the FMQ-G2FS and FMQ-G2FLS.

QUESTION NO. P1129-9: Medion MD1772e monitor. I need value of R241 and marking for Q301. Where I can buy transformer T302 (marking 19*20079*011 LSE)? I have good signal on base Q301 but signal on collector Q301 is bad. There is no HV Collector Q301 is connect to pin T302. Maybe T302 was shorted.

This chassis is similar to the Acer 76e. In the Acer chassis, R241 = 10K ohm, and Q301 is the horizontal driver, actually a small FET, BSS89 (even though the board is marked B,C,E). With R241 bad, ceramic disk cap C327 = 220pF/2KV should be replaced (3KV is best), no matter what its condition seems to be. Also check R329 = 10K, R328 = 4.7K, R326 = 3.9K; 3 Amp. microfuse J013; D308 = UG4D; ZD210 = 5.1V zener; Q302 HOT (2SC5048); Q316 FET = IRF740 or similar; IC201 = TDA4858. Check the solder on the leads of T302 before trying to replace it, but if a source is needed, maybe try that part number with a Mitsubishi supplier (from a Mitsubishi 1772e).

QUESTION NO. P1122-4: Packard Bell 3010 monitor FCC BEJCM710 has no HV. HOT checks good, LED flashing green/amber. Can verify all voltages in SMPS which cycle as monitor clicks. Have checked many components, but cannot locate the fault.

Possible HOT and/or video logic circuit. Check DC rails out of PSU.

QUESTION NO. P1121-6: Dell 800HS series model d825tm monitor. I need the value of the power switching transistor Q602. The manufacturer number on the transistor is w804. Does ECG have a replacement?

Dell D825TM is a Sony-designed chassis which is equivalent to Sony CPD100GS. Q602 is a Mosfet IRFIBC40G-LF38, Sony P/N 8-729-038-51.

QUESTION NO. P1117-4: Mag DX700T monitor. I need values for R102 and R212.

My notes show R102 = 150 ohms, R212 = 2.2 ohms.

QUESTION NO. P1116-6: Viewsonic 17GA monitor when it powers up, or changes scan rates, it takes sometimes over a minute for the screen to reach full brightness. It slowly comes up, from a black raster. The only other side effect, is a little ghosting to the right if high contrast edges.

Try checking capacitors C212 and C215 on the CRT board.

QUESTION NO. P1115-8: View Sonic P810 monitor powers up (no HV), shows low resolution boot up screen then shuts down upon resolution change when windows starts after POST. No raster or anything after shut down just yellow stand-by light. Cannot determine if the problem is Low Voltage section of a HV regulator and HO transistor problem.

This Panasonic chassis has a couple of common problems. The PC board is flimsy, permitting cracks to occur, especially near transformers and big heatsinks. Use magnification to check for these. Also, the electrolytic caps are common to leak fluid, that corrodes PC traces and causes mischief. Any fluid must be cleaned off, and traces repaired. You might check if C852 has leaked, possibly shorting D602. If D602 shorted, check for other damaged components, like C601, R602, R919, Q902, etc, as this would send damaging voltages into the HV protection circuitry.

QUESTION NO. P1114-9: Unbranded OEM version of the 17" KDS EVOKD-1730 monitor FCC EVOKD-1730. On cold startup picture is about 1" high but as unit warms up picture expands, finally being about 70% full size (full size top scan and about 50% bottom scan). Have checked solder joints to no avail.

I would begin at the vertical IC for your OEM chassis. It may be IC301 = TDA8172. Besides the IC itself, check the supply rails (pins 2 & 6 on a TDA8172) for proper voltages during startup. Also check for any leaky electrolytics off these rails, as well as off the output (pin 5) and on the return from the vertical yoke.

QUESTION NO. P1114-6: Dell D1528-LS monitor FCC H4ICM15006. I need the value and sub for Q803 which is blown, only partial ID is possible ?507. Also the original R814 looked to be too small to be 25 watt, should it not be 0.25 watt?

Sounds like Q803 is Fuji's FET 2SK1507, rated 600 Volt, 9 Amp, 50 Watts. Try B&D (www.bdent.com), Dalbani (www.dalbani.com), MCM (www.mcmelectronics.com), etc. for that FET.

Q803 is type K1507 and R814 =1 kohm/0,25 W.

QUESTION NO. P1115-2: Peacock Entrada 17" Monitor. I require the equivalent of diode D113 which has only the marking 31DQ 06 8A as I have one which is short circuit. I tried all the normal sources of cross-reference but no success. There is another of the same type on the PCB and it reads 265 ohms.

31DQ06 is a 3 Amp, 60 Volt Schottky rectifier made by IRF; General Semiconductors' SB360, Vishay's SR306, or Rectron's SR360 might also substitute for it. Digikey (www.digikey.com) lists 31DQ06 and SR306. Mouser (www.mouser.com) lists the SB360 and SR360. An NTE/ECG 579 might also substitute, but would be pricier.

QUESTION NO. P1114-1: Acer 7177is monitor. I need a sub for hot transistor 2sc5048. I tried 2sc4747 n and 2sc5148 but it damaged the hot always. The fbt transformer is okay and tested.

2SC5048 is a 1500 Volt, 12 Amp, 50 Watt HOT. Possible subs include 2SC4890, 2SC5105, 2SC5124, but 2SC5048 itself is often cheaper, and available from places like B&D Enterprises (www.bdent.com), Dalbani (www.dalbani.com), and MCM (www.mcmelectronics.com). Before going further, have you carefully checked or replaced electrolytic caps C307, C353, C3950/51/52, the ceramic disk cap off the collector of Q306, and checked IC201 and FET's Q303 & Q314? Defective components might be causing the HOT short out. Also, D308 may become leaky, when Q306 was shorted.

QUESTION NO. P1114-3: AST RMO7F11 monitor FCC GWGRMO-RTO7FXX, the picture appears on the tube, but it is horizontally squished to only fill about half the screen. Obviously, the digital adjustments do not fix it.

Try checking the 15 Volt zener ZD301, and Q302. If either is bad, check C350 and digital transistor Q350. Also, it is wise to desolder the bottom lead of heatsinked damper D303, and check that its lead extends all the way through the board. If it does not, add an extension wire before resoldering it.

QUESTION NO. P1113-6: AST Vision7L monitor FCC GWGRMO-RTO7FXX. Q346 and Q350 burned, C350 and C343 were popped - need to id Q346, 350 - marked as R1001 504 - unable to cross.

Those transistors are Samsung's KSR1001, digital switches with two 4.7K resistors built into the base connection. An NTE/ECG 2355 might substitute; other possible substitutes include AA1L3M, DTC143ES, RN1001, & UN4222. B&D (www.bdent.com) and MCM (www.mcmelectronics.com) list the DTC143ES.

QUESTION NO. P1019-1: Samtron SC-428PSL monitor with width reduced approx 3 inches both sides. No width control or pincushion control. Checked main semi's no success.

Check Q406 for broken solder connections, also change D407. May test ok but change anyway.

QUESTION NO. P119-5: Acer 1768i monitor. Changed Q306 (BU2525AF) and C3950, C3951, C3952 (no capacity). A month later Q306 blown again. Found C307 without capacity. Is this the cause?

C307 affects the base drive for Q306, so if C307 is bad, it can cause Q306 to fail. Besides C307 and the three 450V capacitors you mentioned, also check C353, and always check the 2KV ceramic disk cap off the collector of Q306, these are common failures. When those three 450V caps go, you should also test the megohm resistors paralleled with them as well.

QUESTION NO. P117-4: Sony cpd 1604s monitor. Related Questions P610-4 and P1011-10. On initial power up (one second or less) green power led comes on and crt face has characteristic HV "feel", then it all shuts down. Actually, the SMPS is still on but is being crow-bared by Q901/NEC5p4m/scr. Isolating the gate on this device allows the +165vdc to come up, and the green power led remains on. It seems Q901 is likely doing its job.

I believe the gate of Q901 is fed by pin 10 of IC401. Check the LM324 op amp on that IC, and perhaps also check D406 and R434 & R435 from the FBT high voltage shutdown circuit. If these are all good, perhaps the HV is truly excessive. I think it should be about 27.5 KV with a B+ of around 68 VDC in VGA mode.

QUESTION NO. P116-4: LG studioworks 44m, 14 inch color monitor is fine when switched on but after a use of app. one hour the image gets blurred and the brightness level increases considerably. All voltages at the CRT remain unaltered ie. the same as when switched on but the pin at screen grid rises from 242 volts to 310 volts positive. It seems that this problem is caused by the increase in screen focus and may be final anode voltages at the CRT. However all the SMPS voltages and the voltage at FB output transistor collector plus the control grid voltage of -100 volts remain stable. Is it the FBT that is faulty?

With no model number provided, one cannot be specific, but certain Goldstar 14" chassis are known for getting bad FBT's with such symptoms.

QUESTION NO. P118-5: Packard Bell 3010 monitor, FCC BEJCM710. I need a value and source for component L701. Only markings are 150-235K WS. Should be an inductor, but no mh ratings.

That FCC# corresponds to Goldstar Chassis# CA-42, same as a Studioworks 74i, so try LG Electronics (formerly Goldstar), or a Goldstar distributor, such as Astro or Shine Electronics, for that chassis's L701 part number.

QUESTION NO. P116-6: Three Dell D828FI monitors (seems to be similar as Samsung 550??) with same problem. While warming up, picture becomes distorted in vertical direction. Vertical vibrations appears too. Top 1/2 of picture is expanded and bottom 1/2 of one is pressed. Freeze spray has no affect around IC TDA9302H.

The fault symptoms suggests that the TDA9109 needs replacement. This i/c provides hori/vert etc processing.

QUESTION NO. P116-9: IBM 2124 -001 monitor, manuf. date dec.97, it has a Samsung CRT (mod# M36KUQ35X92) (SKD). The part # of the main PCB is 55.78520.001. I need the value of C335 on the main PCB or any useful info in identifying or cross referencing (the cap is burnt beyond recognition).

This chassis is similar to the Acer 7154e. C335 is a 220 pF/2KV ceramic disk capacitor, but is better replaced with a 3KV rating. Mouser (www.mouser.com) carries such caps.

QUESTION NO. P1010-9: Samsung Sync Master 17GLsi monitor. I need the capacitance and voltage values of C429 and C430. They are both connected to the HOT.

I believe that I have the same monitor as in question, basic model no. CMH 7379L SyncMaster GLsi, main board model CMH 73*9 rev. 2.01. The C429 on my board reads "252J2500V BUP 509" which means 25 x 100pF J = +/-5% tolerance 2500V. The C430 "202J 1600V BUP-S" = 20 x 100pF J = +/-5% tolerance 1600V. Don't know what the other letters/numbers mean,could be some temp. range. Apparently 100.000 pF = 1uF. I am just a layman in this so the following info was based upon the following resources http//www.xtronics.com/Kits/ccode.htm and http//www.ee.washington.edu/circuit_archive/capacitors.html. Other useful info are at http//www.us-epanorama.net/main.html.

QUESTION NO. P1030-10: Samsung CQA4147 monitor turns on OK, but only shows a horizontal line on the screen.

Try checking the vertical IC, R301, and R307.

QUESTION NO. P1030-7: HP D2818A monitor FCC A3LCMG737. There was an interrupted "funny" resistor R508 (looks like a fuse?). I need the value and cause. I replaced it by resistor 1 ohm. Everything was O.K. but after repowering-up Q502 and Q503 have gone.

R508 is a 1 Amp, 125V Fuse. Sometimes Q502 just arcs through its insulation, and takes out that fuse, and maybe also the B+ regulator. But you might also check Q416, the FBT, and the CRT for shorts.

QUESTION NO. P1027-10: IBM 6544-403 monitor has raster but no video. However, when powering down video is momentarily present. Replaced LM1205 on CRT pcb-same.

On this G70 model, when there is no video with the signal cable still attached, but the picture flashes on the screen during shut-off, the usual cause is a bad rubberized-membrane control panel (under the CRT face), which must be replaced.

QUESTION NO. P105-8: Ampro 1100 video projector manufactured by Zenith. Ampro is no longer in business so I would need to know the Zenith model number for this projector to get a service manual from Zenith, it was manufactured in 1993. When turned on, it powers up, and after a second or two the high voltage shuts down, the Conv/HV SMPS voltage is 145.

Check the FCC ID CODE located on the the back of the unit (on the same sticker as the model) where the first 3 digits identify the manufacturer and the remaining digits identify the model, then visit www.fcc.gov/oet/fccid/ to locate contact the OEM, Zenith 1-800-243-0000 (Alabama)

QUESTION NO. P1027-4: CTX VL700 monitor. Need value of R341 (source resistor of Q311) burnt beyond recognition.

R341 is a 47k quarter watt.

QUESTION NO. P1026-4: Gateway 2000 CS1572DG monitor. Need replacement/cross for D509 (has FUF4004 on it).

FUF4004 is a 400 Volt, 1 Amp, ultrafast rectifier. General Semi's UF4004 or IRF's 11DF4 are replacements. Mouser Electronics (800-346-6873; www.mouser.com) lists UF4004. Other possible substitutes are HER105, SF16, and NTE/ECG 574.

QUESTION NO. P1023-10: KDS KD-7300 monitor, FCC EVOKD-1730. The screen cracked a few times, then went dead. LED flashing and power supply clicking. Checked for burned components and diodes, OK. Found HOT (Q411) shorted, replaced. Powered unit back up, HOT shorted again. Saw a brief puff of smoke, didn't last long enough to see location...nothing looks burned.

Check for bad solder on the flyback, W404, and yoke connector, and for bad crimp connections in the yoke connector plug, that may contribute to failure. The flybacks in this FCC# are common to fail in the ABL winding, and burn one or more of resistors R901-R904, sometimes also shorting IC401. Also, with your symptoms, you might check Q406, C438, C447, C455, D402, D407, D411, and L401.

QUESTION NO. P1024-3: Relisys RE767B monitor is dead. Replaced shorted HOT (Q504). Unit now functions but T501 runs hot and shows signs of previous overheating, i.e. puddle of brown goo at base, which appears to have melted from interior.

If T501 is marked 7351170016303 CHI 9819, or similarly, Nationwide Electronics (888-634-7278; www.neiparts.net) has been able to special-order this coil before.

QUESTION NO. P106-10: Apple colorsync M3705 monitor displays half screen verticle when connected to computer, but internal signal, controls etc. display ok.

Check connector of H-deflection yoke for bad solder joints. In that case, QL-23 is also bad (replace!). Replace RL163 (even if it measures ok!!). Another cause is a bad capacitor CL-9. Most of the time one pin is burnt. In that case, replace the capacitor and also the above QL23 abd RL163. If this does not solve your problem, check if the collector of TL23 is about 50-60V dc. If not, check QL2. We had two cases with the same problem caused by a shortcircuit between QL3 and the heatsink (replace the siliconrubber).

QUESTION NO. P1024-10: Gateway yeo711 monitor. I need the value of D112and R115, keep blowing horizonal outputs.

D112 is IRF's 11DQ06, a 60V, 1.1A Schottky rectifier; R115 = 0.18 ohms.

QUESTION NO. P1023-5: We have (8) NCD CM3800 monitors FCC A3KM053 with no video.

Two common problems seen with FCC# A3KM053, are bad R573, a 1 ohm resistor by the yoke connector on the main board, and bad flybacks.

QUESTION NO. P1020-5: Imagic 778L monitor. I need the value of R634 and the cause of it burning.

R634 = 3.3K, 1/4 Watt. A bad flyback is the common cause for burning this resistor. Also check the HOT Q521 = BUH1015HI, and R633 = 12K ohm.

QUESTION NO. P1020-3: Acer 716ie monitor with pincushion distortion. Pincushion control still works but cannot adjust enough. Replaced C3950-3952, C353, C320 (100pF, 2KV), with no improvement.

If this is actually an Acer 7176ie, try checking Q312, Q313, and D308 for excess reverse leakiness.

QUESTION NO. P1019-9: ProVista PD-959 monitor, FCC IDBR8PD-959. First no H.V. Q563(2SK10069, Q831 (BU2520DF) was shorted and R866 (2,2ohm) was burned. I replaced, when turned on Q563, Q831 and R866 there and then damaged. There is no signal on B-Q831 and G-Q563 but signal on S-Q830 (BSN254A) is o.k. Signal for horizontal output is 800Vpp and always work good.

Try replacement of the flyback transformer T806, LZ250A000P, Sampo FEA662, when those components repeatedly die.

QUESTION NO. P1018-6: Acer 54e monitor with c335 burned (blinking led and no picture). Should I replace c335, r214, d316, d317 and q317 (info from other questions)and if so what are the values of d316 & d317?

Replace C335, when it is burnt. Mouser (800-346-6873; www.mouser.com) is one source for the 220 pF/3KV disk capacitors, as well as the ultrafast UF5404 (D317). Components other than C335 only need to be replaced if they are burnt, off-value, shorted or open. Sometimes the diodes and the FET aren't totally shorted, but have high leakage in the reverse direction. If R214 is bad, consider that IC201 = TDA4858 may also need to be replaced, and if Q317 (IRFI630 or 2SK2161) is shorted/leaky, also check coil L304. And don't forget to check out Q310 = BU2525A.

QUESTION NO. P102-10: Voxon MO-D1428 monitor FCC LFVDX-1448. I need the value of r825.

R825 is 0,47 Ohm resistor Yellow Violet Silver Gold. If burned again the flyback is short and you are out of luck. Supplier is out of bussines and no way to get it so far.

QUESTION NO. P929-5: Daytek (Daewoo) DT-1536 monitor with no vertical sweep, only a bright line across the middle of the screen from left to right.

Poor solder connections on the vertical ic causes this problem. Replace the ic and check associated caps. Also resolder the flyback pins.

QUESTION NO. P1010-5: Dell D1528-LS monitor, R814 in the power supply is smoked. I need the value of it, plus, are any other components in that area likely to need replacement?