36) dell 수리내역

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QUESTION NO. P101503-8:  Dell 1028L monitor.  What is the value of the ph-33d?

Without the component's chassis location number, the service literature cannot be referenced, but this may be a Philips fast-recovery type rectifier, BYD-33D, rated 200 Volts, 1 Amp. Possible substitutes for that one, are FR103, NTE552, or NTE574.

QUESTION NO. P72403-3:  Dell p991 19 Sony monitor,  I am measuring 30 KV for high voltage and unless I lower brightness and contrast  down to 30% of full the monitor goes into shutdown.  How can I lower HiV to 26-27 KV?  When I pull crt socket off the tube all is OK, so I'm guessing its excessive beam current.

According to the manual, HV is adjusted to 27KV by RV901 (on D board, under a cover and RTV silicone). Also, check components in the HV regulatory circuit (R924, R925, RV901, IC901, and FBT T901), and the HV and ABL protection circuits (R917, R918, R920, R921, R923, R932, R933, R191, R1004, R1006, C920, D911, D912, D915, D917, IC901, T901), in case any are off-value or faulty. Note, Defective FBT's (Sony p/n# 1-453-317-11) are one cause of 30KV HV in this model.

QUESTION NO. P72103-1:  Dell GDM-5001PT monitor does not respond to the controls for vertical center and vertical size, also has pincushion on both sides.  How do I reset ic007 in the D board, CXA-2043Q like Samsung TV's?

This Dell is a Sony, not a Samsung, chassis. The symptoms sound more like a defective IC007, than one that needs realigning via Sony DAS software. If you replace IC007, beware of lifting the fine PCB traces. Sony distributors have CXA2043Q, as Sony part number 8-752-078-46, or MCM Electronics may have the generic part available.

QUESTION NO. P70903-4:  Dell P1110 monitor, G2 dies out after 1 to 2 hours, spraying coolant on Q406 brings back the picture.  Q406 is surface mounted with no visible markings, what is the generic part #?

In the Sony Manual, Q406 is either a Matsushita 2SB709A (in the schematic), or a Toshiba 2SA1162 (in the parts list); these two PNP transistors have similar specs. The parts list shows Q406 as 2SA1162-G (G = gain bracket 200-400), and Sony p/n# 8-729-216-22.

QUESTION NO. P61703-2:  Dell D1626HT monitor (Sony chassis SCC-L04K-A) with no red color. After check and replace de IC403 (FA4111) without result, I think the problem can be caused by malfunction of IC402 (M52722P).  I haven't any datasheet of M52722P and I can't find in Mitsubishi Semiconductor site.

In the schematic, the Red input to IC402 is to pin 17, and is about 2.8V. Red drive (pin 18) is about 3.9V, Red hold (pin 35) is about 4.4V, and Red Output (pin 37) is about 2.7V. Vcc for red (12VDC) is IC402, pins 16 and 36; red ground pins are pins 24 and 29. Red output goes to transistor Q101 (PNP, base is about 2.8V, emitter is about 3.5V), then continues on to input at IC403. If another IC is needed, IC402 (M52722P) is Sony part number 8-759-468-63.

QUESTION NO. P42303-2:  I need the Sony manual part number for a Dell P992 monitor.

The number on the P992 service manual is 9-978-704-01.

QUESTION NO. P41703-4:  Dell P1110 monitor (Sony chassis SCC-L22D-A), the CRT heater voltage is muted.  Applied external CRT filament supply, the picture appeared, but the screen is too high.

Most times in the case of the missing heater voltage, there is usually a dried out electrolytic capacitor or bad inductor coil in the circuit. Check for one or the other. If the capacitor you find is suspected to be bad, you can parallel a known good one across it. If it is bad this should restore heater voltage somewhere around 7 volts DC.

QUESTION NO. P41503-4:  I need a Sony part no. ( 8-xxx-xxx-xx )  for a Sony IC (CXD9164M) from a Dell P992 monitor.

The Sony manual lists IC003 (CXD9164MTR) as Sony p/n# 6-700-723-01. (Not "8").

QUESTION NO. P31303-3:  Dell D1025HT monitor has dim picture and no red color.

This was a comman fault of VPS12 IC.

QUESTION NO. P32403-7:  Dell  p991 monitor has no video.  Replaced Q901 (Irfi9634g) and Q902 (fs5km-18a, replaced with nte2958) both shorted.  I checked R934, C507, C644 and C914.

Since Q901 and Q902 are for driving flyback transformer T901, I would check if the FBT is bad. Also check gate-protection zeners D906 (10V) and D909 (15V), as well as B+ cap C913, and ultrafast D907. If the G2 voltage is low/missing, check R916, D910, and C919. An FS5KM-18A is rated at 900 Volts, a higher rating than NTE 2958 (700 Volts); is that NTE substitute FET still OK?

QUESTION NO. P31403-8:  Dell 1600h model D1626HS (Sony Chassis).  I need the value of missing Q640 in power supply.  R640 is open and looks like C641 has been replaced as there is carbon marks around it.

Assuming this model is actually the Dell/Sony 1600HS/D1626HT, Q640 is the dual transistor, MX0841AB-F; you can get this from Sony, as their part# 8-729-041-12.  R640 = 0.1 ohm, 1/2 Watt, fusible; C641 = 470 pF/500V, ceramic.

QUESTION NO. P30503-7:  Dell Ultrascan P780, chassis SCC-L29K-A: monitor clicks on power up and then green light will turn amber and flash. HOT and all other components tested OK.

HV/+B  failure   Blink Amber on 0.5 sec off 0.5 sec.

H stop or V stop (included S-cap          Blink Amber on 0.5 sec off 0.5 sec.

ABL Failure      Blink Amber on 0.5 sec off 1.5 sec.

Aging/self-test  Blink Amber on 0.5 sec off 0.5 sec Blink Green on 0.5 sec off 0.5 sec.

I think the H stop or V stop is Amber on 1.5 sec: off 0.5 sec.

QUESTION NO. P102802-10:  Dell ultrascan P1110 monitor with an excessive brightness/raster with slight color purity problem.  Fault seems to be on small logic board situated on the base of the monitor and I am am unable to pinpoint the fault.  The board has a Sony ic, I changed the whole board to cure the fault short term, but I am seeing more monitors like this.  There are no adjustments other than focus.

This Dell is like the Sony G1-chassis types, and it sounds like it needs a Sony DAS (software) alignment, which can adjust the G2 voltage (assuming yours is excessive), as well as adjusting the white balance.

QUESTION NO. P80102-9:  Dell UltraScan 1000HS Model D1025TM monitor, I need the value of R577 (located near in front of the HOT Q507).

If this Dell is a Sony chassis code SCC-L07 type, like the Sony CPD-200GS, the schematic lists R577 as 12 ohm, 2 Watt, 5%, fusible.

QUESTION NO. P62002-7:  Dell Ultrascan 17FS-EN monitor (Mitsubishi TFS6705) has no high voltage.  On gate of Q603 there is an H-drive pulse of 500mVpp and 168V via T601 at its drain but it does not pulse.  Are they good values?  I changed Q603 but it continues and I have not found broken parts around it.  All controls and power supply voltages are good.

Be sure the fan is running at the correct (3300) RPM.  If the fan runs too slowly, and its pulse circuitry sends pulses too slowly, the monitor will shut down the HV.  Sometimes the fan's bearings just need lubrication; the pulse circuit also can go bad.

QUESTION NO. P53102-5:  Dell 828FI monitor 800F series works fine until turned off and back on, or reboot PC, than LED flash green twice as fast (blinks when connected to non working PC and constant ON when computer is on) but no video.  Turn monitor off and disconnect from computer for about 5 minutes, connect again, turn on and everything works fine again until you reboot PC or turn power off and on.  When power cycled on off on I can hear slight buzzing noise (very slight) like it is not enough power to kick in high voltage ether on power supply or on the flyback.  I replaced hot Q406 transistor and the D403 with no effect, replaced C503, C606, C515 nothing changes. Replaced TDA 9109, it did not help.

The micom ic202 supplies OSD,to the video board.vert/horz sync to TDA 9109.  According to Samsung, check H/V pulses Pins 4 & 10 of ic105 NO check ic105 OK same H/V Pins 20&21 ic202 NO ic202.The other ic is the E2EPROM ic205..There is a reliability mod for this chassis.  With chassis removed, clean the lower edge of the bell CRT.  Glue a piece of foil (3inches wide 10 long) along the bell over-lapping the rim band.  This is to prevent static discharge from the CRT from damaging ic302 or the CPU.  Many of the common faults on this product are attributable to ic302.

QUESTION NO. P50702-6:  Dell D1025tm monitor (Sony CPD200gs) has a fuzzy picture.  The keys on the front are locked up. When I press anything but the menu, I get a picture of a key in the lower left corner.  The menu will only let me move between two of nine menu choices.  How can I unlock it? Do I need the DAS software to do it?  Dell could not find anything about it and the Sony manual does not say anything about locking the menu.

The Sony CPD-200GS does have a "Lock" Option in its OSD Menu; perhaps the same procedure is used in your Dell.  Press the "Menu" key, use the arrow keys to toggle Up/Down and Left/Right, to select the "Option" Menu (at lower right), and then press "Menu" again. Several Options will appear, including a Key Icon. Toggle up/down to the Key Icon, then use the Left/Right keys to turn it off. Regarding the fuzziness, try going to the "Screen" Menu (upper right), and adjusting the H or V convergence, or the Moire.

QUESTION NO. P43002-4:  Dell D1025TM monitor, how do I adjust the screen controls , and the gain for the red, blue, green, (there are no pots).  Is this chassis a Sony?  What is the Sony Model?

This Dell is similar to the Sony CPD-200GS model.  Service adjustments in that Sony model are done with the Sony DAS software and interface adaptor.  Using the user OSD controls, brightness and color temperature levels may be selected.

QUESTION NO. P220-8:  Dell Ultrascan P780 monitor appears to power up, No green / amber light.  Fuse OK. 120 through the fuse.

Check the Horizontal Output Transistor. It may be Open, or otherwise failed.

QUESTION NO. P130-2:  Dell D1226H monitor FCC A3KM073 has no video.  Found Q7543 (MTP5P25) shorted and R3544 burned.  I need the value for R3544.

R3544 = 1 ohm, 1/4 Watt, fusible. Also should check Q7532, D6534, and L5526.

QUESTION NO. P1212-7:  Dell 1728-LS monitor, built by Samsung.  The raster, color balance, purity, convergence and screen display are all normal. The brightness and contrast controls are operative, but the maximum brightness is very low.

See if the screen voltage or the heater voltage is low.  If the heater voltage is bad, check the solder, and the value, on components going to the heater, including SMPS transformer T601, D617, R620, C644, J311, J309, CN603, CN105, R165, etc.  Also check the ESR, as well as value, on C644. If these are all OK, try checking the CRT emissions.

QUESTION NO. P1119-4:  Looking for correct pinout to a Dell D1028LR monitor with Philips CM6800 Chassis (FCCA3KM066). The cable is cut at the VGA connector, pinout for the VGA is no problem, but I need the pinout for the internal connector.

www.epanorama.net/links/repair.html.

QUESTION NO. P117-7:  I need the pinout of the signal cable of a Dell M990 monitor FCC A3KM085 (Philips)?  The cable is cut at the monitor side. (I know the connector-pinout, need the pinout of the internal connector.)

www.epanorama.net/links/repair.html

QUESTION NO. P927-2:  Dell d1025he monitor FCC iey447s.  I replaced the hot as it was shorted.  Now on turn on, there are power supply voltages but nothing on the collector of the hot.  I am getting the correct pulses on the base of it but still no H.T.

See if R411 has gone open-circuit.  If so, before powering up, also check D404 and T404.

QUESTION NO. P1023-2;  Dell D2026T-HS monitor is very dark (only can shows the OSD).  We found a low G2 voltage, the G2 control transistor is ok.  Is there a protection control circuit that shuts it down?

Assuming that your Dell's FCC number shows that it is a Sony GDM20E03 chassis, the probable cause is a defective IC, CXA1907S, on the CRT board, Sony part# 8-752-071-56.  If the output voltage from pin 22 of the CXA1907S is too low, going to IC407, this will cause low G2 voltage.  To remove the old IC without lifting PC traces, it is best to cut off each pin, and remove the pins one at a time.

QUESTION NO. P1019-9:  Dell 828Fi monitor.  During bootup sequence, it seems to loose horizontal sync and controls have no effect. I suspect TDA9109 might becoming progressively faulty, but I would like confirmation.

TDA9109 is a common failure in this chassis, and it can give a variety of symptoms, such as jitter, bad linearity, loss of sync, loss of user settings, etc.  Try some freeze mist on the IC, sometimes that helps diagnose it.  If this IC is replaced, be sure to use the exact same version of TDA9109, as was originally installed; TDA9109 and TDA9109/S are different chips.

QUESTION NO. P103-10:  Dell UltraScan 17TX monitor FCC AK8GDM17SE2T came in with tilted picture and blurry screen.  Adjusted the screen and focus controls and got focus, however, the words and letters are in the 3 primary colors, red, green, and blue.  Cannot seem to get the (Purity or Convergence?) adjustment in.  The screen tilt was temporarily fixed by disconnecting a wire on the Yoke board.  Screen came in with all yoke and crt adjustments loosened.

You are going to need a service manual, to correctly adjust the purity.  Try to get the manual for a Sony GDM-17SE2T, which should be similar, from a Sony distributor.

QUESTION NO. P925-4:  Dell D1728D-LS monitor, FCC A3LCMG737 will not power up,.no response.  Switching power supply appears OK except no 12VDC at one point on board.

Check if R508 has gone open-circuit. Depending on the A3LCMG737 board version, itcan be either a small-value (1.8, 3.3, etc, ohm) fusible resistor, or a 1 Amp microfuse,on the 195V supply. If it is bad, also check if HOT Q502 has shorted, as well.

QUESTION NO. P828-10:  Dell D2026T-HS Ultrascan 20TX Sony vertical is very unstable, poor pincushion.  The front controls will not adjust the vertical width or position.  I am suspecting the circuit around ic 502. I replaced the vert ic TDA 8172, and all electrolytic caps around it with no effect.

I am more suspicious of the IC007 (Sony part# 8-752-076-34), on the D board, than of IC502, for this type of problem; it's a known failure component.

QUESTION NO. P919-7:  Dell D1025TM monitor (Sony chassis) with bad HOT, damper diode, and fet w/protect zener.  I can locate the original HOT, and fet w/protect zener but cannot find the damper diode. The only numbers on the diode are DLA 8-J.  Sony does not support this monitor and Dell has been unresponsive.

Toshiba makes a family of rectifiers with the marking "DLA" and a date-code.  Although it is not the damper, I suspect you are referring to D516, a Toshiba 3DL41A, a 3 Amp, 200 Volt, superfast rectifier. The original is Sony part# 8-719-051-97; similar rectifiers include NTE/ECG 588 or Rectron's SF34.

QUESTION NO. P910-10:  Dell D825tm (UltraScan 800 series) monitor, very dim picture.  C653 which filters the line going to the filaments is missing.

Try 2200uF/16V for C653.  This is a common value for filter cap of filament supply.  Filament should be around 6.3V generally.

QUESTION NO. P917-4:  Dell D1028LR monitor comes on, but goes off when computer is restarted and refuses to power up again.  No green light, yellow light flickers sometimes. 

Replace component 3110. (Resistor - 220K, 1WJ)

QUESTION NO. P79-5:  Dell d825ht monitor has vertical foldover on the bottom portion of the screen.  I replaced the vertical output with no luck.

Is there a solid -10 VDC on pin 4 of the vertical IC?  If not, try checking components on this line, such as C401, C403, D653, C653, and L653. Also, pin 2 should be +16 VDC.

QUESTION NO. P618-8:  Several Dell P1728U monitors which have a non standard pin configuration.  Where can I get cables?  I really do not want to open them all and move the pins around.

The Dell P1728U is a Mitsubishi-made chassis, and Mitsubishi uses a nonstandard pinout.  You might get cables from a Mitsubishi supplier, or check with KMR Technical Services (www.kmrtech.com), about their cable VCDB-003.

QUESTION NO. P46-5:  Dell UltraScan 1000HS, Model D1025TM monitor will no longer power up.  About every 5-10 seconds it makes a high-pitched chirp.  Previously the monitor would only power on and give an orange light, even with a signal connected.

First, check the following components, Q507, Q520, Q501, D503, D516, D614, C622,and IC605.  If these are all OK, or if the flashing orange LED returns, suspecta bad CPU IC, IC901; it has been a common failure in this Sony chassis.

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. 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. 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. P39-1:  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. 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. 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. 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. 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?

Value for R814 is 1kohm 25watt.  Check to make sure R801, R810 are not open.  Check if Q803 or I801 shorted.

QUESTION NO. P104-2:  Dell 1528-LS monitor, with burned resistor (R468). I need the value.

The value is 21ohm 0.5W +/- 5%.

QUESTION NO. P104-3:  Dell V1728E monitor that starts jumping/scrolling after warm up.  Changed all caps in vertical stage, still the same. When certain caps and IC(TDA9102C) are sprayed with freeze(just a two second burst) jumping stops. I suspect IC but not sure.

A defective TDA9102C IC can indeed exhibit a vertical-jumping symptom when warm.

QUESTION NO. P922-10:  Dell 1528 LS monitor (lite-on FCC H4ICM15006). The red color does nit work.  I replaced Q901 and Q902 (2sc2851 and 2sc3611). With an osciloscope I can see that the red, green and blue signals going in I501 (MM1203) have the same level.  The outgoing signal of red is about 10 times smaller then the signals for blue and green. I can't find a manufactorer or a datasheet of the MM1203. The IC tell's me it is made by Mitsumi but on their site they do not know it.

The datasheet for Mitsumi's MM1203 is at www.mitsumi.co.jp/Catalog/ic/visual/mm/1203/text01e.pdf MM1203 is similar to LM1203AN (or LM1203BN), and you should be able to sub one of those parts for it.  B&D Enterprises (800-458-6053; www.bdent.com) lists LM1203AN. A plain LM1203N is slower than MM1203, and may not be a suitable substitute for it. You might also check the components off pins 5, 26, and 27, as these inputs will affect the red output channel (pin 25) as well.

QESTION NO. P96-8:  Dell (Sony) d1526t-hs monitor.  When started a click is heard, then the power and the power save light begin to blink, simultaneously.   No hv, but B+ is approx 30 v and the other voltages also very low.  Checked that the power supply works, but apparently in a standby mode. When power switch is pressed the green light gets steady but soon reverts to blinking.  Replaced the HOT, which was shorted. The low voltage to operate the smps is 6 v but should be at least 8,5 v.  Checked all the diodes, caps. What makes the unit adopt a standby mode?

This is a Sony 15SF1 chassis.  These go into a shutdown mode when the circuitry detects faults, so there are numerous reasons why yours may have gone down.   Most common are cracks in the board traces, and bad solder, particularly towards the board center, and around the big heatsink, and including the solder on heatsink rivets. Since the HOT was shorted, other components to check include FET Q503, C599 = 22 uF/100V, D504, Schottky D508. Also check if the N board is regulating the Horiz. drive transformer voltage properly; pin#1 of T504 should be about 60 VDC in 640x480 mode.

QUESTION NO. P728-2:  Dell D1728D-LS monitor powers up, no high voltage.  Checked the HOT and Diode (D405) along side the flyback cage and they check out fine.  Flyback appears fine.

Check if R508 is open.  Check Q416 and Q502.  Once in awhile, the insulation coating on Q502 has arced through, and transistor is bad even if it tests good, so check for this too.

QUESTION NO. P721-4:  Dell Ultrascan 21FS-BEN monitor July 1994 manufacture, no cable supplied.  Looks like oo::::o.  Need part number/supplier.

This cable should not be hard to find, it is used on many monitors ie Nanao and IBM (IBM cable has these nubers on it.  FUJIKURA-T part#96g2156 e.c. # 003021B).

QUESTION NO. P65-2:  Dell d825tm ultrascan 800 series monitor the display is very dim.  Fault is not with crt or lopt.

The cap that filters the filament voltage in the switch mode power supply is bad c632 I think that is the correct location very smal 470 uf cap next to a 1000 uf cap in the switch mode.

QUESTION NO. P47-8:  Dell 17fs-n monitor, video is very washed out with green screen and retrace lines.  Focus works as does screen control.   Voltages appear to be correct.

Check if there is a short between the green cathode, and either G1, or the heater.  If there is no short in the CRT, then on the CRT board, check hybrid IC202 (Mitsubishi OEM# CP267P042A30), Q2B0, IC203 (LH2426H), and if necessary, the SMD IC on the back of the board, IC201 = AN93B04SCR (Mitsubishi OEM# CP263P05701). If you need parts, this chassis is similar to a Mitsubishi Diamond Pro 17, TFS6705SETK, so either try Mitsubishi itself (e.g., 800-447-7703), or else a Mitsubishi supplier, like National Parts Depot (800) 524-8338 or Comprex (800) 526-8611.

QUESTION NO. P320-2:  Several Dell D1528-LS monitors go blank shortly after powering on, the led remains green.  Pushing the button off/on the picture appears for a moment then the same problem occurs.  I changed the capacitor ( 220킚 400 V ) but it does not work.

I am not 100% sure if your screen is the same as mine but I have had similar faults on three Dell screens that go blank after about 1hour or longer.  The fault was caused by the main Z80 based processor (test to see if control panels lights work correctly, if they have locked in one position or operate in a strange way this is likely to be the fault) which I think is available Richardsons.

I removed IC701 (Zilog 860204 Keyboard Controller) and reinstalled the same part after not finding a replacement.  The monitor has worked now for 2 days without blinking. I suspect there is oxidation on the socket connections and removing and reinstalling the same part has made better connections to the socket.

QUESTION NO. P328-5:  Dell D2026T-HS Ultra Scan 20TX monitor.   Initial problem is a very dim image. Investigation reveals that G2 voltage enters neckboard at approx. 1000 volts.  By the time it reaches the CRT socket it is down to about 80 volts.  I believe it should be at least 120 volts there.  It appears that Q407 and Q403 are involved in controlling the G2 voltage.  After temporarily installing a focus divider to bring G2 up to about 120 v. the image is much brighter , but there are now random retrace lines flashing across the screen.  Everything else "appears" to be as expected.

The most common failure component for G2 problems on this chassis, is IC402 = CXA1907S, on the CRT board, Sony p/n#8-752-071-56 (get from Sony, or try CCS). The old IC is hard to remove safely; it works best to clip off each pin, and remove the pins one at a time.  But before buying this IC ($40+), you might want to check first with a CRT tester, to ensure that the CRT has good emission.

QUESTION NO. P316-1:  Dell D1528 LS monitor, after one hour the display goes off.  The high voltage remains and the monitor displays again if switched off and then on after a few minutes.  The on time gets shorter with time.   Capacitors C826 and C828 becomes very hot.

You should change the caps, especially C826, it gets leaky; also check C823 and C841.  There is a good chance the Zilog Z860204PSC microcontroller (I701) is going thermally bad.  Does freeze spray affect it?  Does the front panel LED change color at shut-off?  Try NEI (www.neiparts.net/cmparts/semiconrecent.html; 888-634-7278), or CCS, for a replacement Zilog if you need one.  It has also been recommended to glue a metal strip to the top of of the new IC, and ground the metal, to protect it against damage from arcing.  It is also possible the Eeprom (I703) is bad; if needed, try NEI or LJ Enterprises (800-627-8755;  www.ljent.com) for the preprogrammed Eeprom.

QUESTION NO. P127-8:  Dell D1726S-HS Monitor powers up and comes on, good video but relay will start clicking.  This is intermittent, and the screen will blank.  It does not cycle at any given interval.  Sometimes unit has played several minutes, 30-45 before doing and others does it when first fired up.

This could just be a bad solder connection somewhere. Also, in one case of this symptom, on a related chassis, it was caused by a 7805-type voltage regulator (IC651), which was being overloaded a bit, and occasionally activated its internal shutdown circuit.  Replacing it with a heftier regulator (a L78S05CV from Mouser Electronics, 800-346-6873) with better heatsinking solved that one.  Perhaps a corresponding voltage regulator IC on your chassis is doing this. If either of these is not the cause, then I'd check out the hybrid IC, HIC601 = MP17H.

QUESTION NO. P1115-2:  Dell ultra scan 17FS-EN monitor with no green color.  I need the value of "IC201".

This is a similar chassis to the Mitsubishi TFS6705SETK; IC201 = AN93B04SCR, p/n# CP263P05701, a 28-pin SMD IC on the video board. Maybe try Nationwide.

QUESTION NO. P99-6:  Dell D1028LR Color Monitor ( Phillips Manufacture Chassis CM 6800).  Problem Horizontal collapse, thin line down centre of monitor).  I have checked for dry joints on scan coil connectors etc & continuity of the coils themselves.  I replaced Diode 6632 which was short circuit (BYV 36C).   This was in the scan circuit, however on switch on it has made no difference.

According to a technical bulletin from Philips, check R3550 if open perform the following: Replace- R3550 1.5ohm 1/4 w 4822 052 10158, Q7520 mtp6p20e 4822 130 63882, Q7630 BU2527A 4822 130 63627, add Q7523 4835 130 47173 (grid c-12 on schematic,CBA prescreened and drilled), remove choke L5502, remove jumper 9605 (grid B-12) and replace with a 1ohm resistor 4822 052 11108, add 220ohm (4822 116 83872) from collector of Q7518 (grid D12) to jumper 9128 (grid F8).  This is the second bulletin (and most recent) for this problem.  Grid numbers refer to grids marked on the schematic.    Philips service manual number 6595.

QUESTION NO. P827-9:  Mitsubishi Diamond Scan HA-3905ADK Monitor.   Read here that their Cable for Dell/Mitsu monitors is not a standard Cable like for VGA.  Is that true for this model?  I have been trying to align the picture to my test box, but it is all over the screen, cannot seem to sync.

Yes, this model uses a different cable pinout from usual, and using standard VGA cables does give that sync. problem. The Mitsu. cable's pinout, on the monitor side is, pin #2 = red; #3= red ground; #4 = green; #5 = green ground; #6 = blue ground; #8 = vert. sync.; #9 = horiz. sync.; #10 = blue; pins #1, 7, & 11 - 15 are no connection. The cable's pinout, on the computer side, is, pin #1 = Red; #2 = Green; #3 = Blue; #4 = ground; #6 = red ground; #7 = green ground; #8 = blue ground; #10 = ground; #11 = ground; #13 = horiz. sync; #14 = vert. sync; pins #5, 9, 12, & 15 are no connection.

QUESTION NO. P826-10:  Dell P1728U monitor.  It has a Mitsubishi chassis TB92108801.2.  I replaced the shorted HOT and it worked for about 10 seconds until the HOT shorted again.

If you found the HOT Q503 shorted, what was the condition of Q534, the P-FET that regulates its B+? When this P-FET (usually a 2SJ307) goes, it overvoltages the HOT.  Also check for any bad components (diodes, resistors, etc) off the gate of the FET, to avoid more blowups. If, when you say the new HOT "worked", you mean the unit powered on, but you didn't actually see a full display briefly, then it is also reasonable to check the horizontal yoke coil and/or the CRT for shorts as well. If you do need 2SJ307, you might try B & D Enterprises (800-458-6053) or MCM (800-543-4330).

QUESTION NO. P511-8:  Dell p1728u monitor. The monitor powers up but there is no display.  The contrast and brightness leds are flashing on and off.   I have changed ic 902 already.  Also the neck is lit up which appears that there is high voltage.

I think you will find that this "Dell" monitor is actually a Mitsubishi chassis.  This Mitsubishi's video cable does not use the standard VGA pinout, and using a standard VGA cable will not give any video.  Get the customer to bring in their video cable for this monitor.  If you have to make your own, the pins going into the monitor are pin#2 = red; #3= Red ground; #4 = green; #5 = green ground; #6 = blue ground; #8 = vert. sync.; #9 = horiz. sync.; #10 = blue; pins# 1,7, and 11-15 are no connection.

QUESTION NO. P56-8:  Dell ultra scan 17tx monitor, shuts down after about 2 seconds,and the amber LED flashes.  No horizontal startup.  I checked the H trans. and related components, all check O.K. The 5-volt stand-by voltage remains after shut-down,but all other voltages come up about half-way then shut-down.   Checked continuity on video cable, also checked Q417,420.

This "Dell" is probably has a Sony FCC#. If so, a common failure part in those is R613 = 390K (if value bad, replace with 0.5W rating, also replace R612 & C600).  Check all "PS" type fuses (PS401, PS402, etc, around 8 total) and R638 for open; check IC401 = LM339 type, & IC403 = LM324 type; also check diodes D441 through D446. Check if VR401 is set for ~28KV. Sometimes the Eeprom goes bad in this Sony.

QUESTION NO. P56-6:  Dell D1726S-HS monitor.  I need a hibrid ic location on pcb is HIC 401, on the part you can read this HS17 IEKS.  Who is selling these parts?

If you check the FCC#, you will likely find that your "Dell" monitor is actually made by Samsung. If so, try getting this HIC from a Samsung supplier. In the US, for Samsung parts, you can try Herman's Electronics (800-938-4376) or J&J International (800-627-4368) on the east coast; Amcotron (800-344-3882) on the west coast; or maybe Samsung itself (800-726-7864).

QUESTION NO. P416-7:  Dell D1025HE (FCC IEY447S). The height of the picture is too small (vertical), top is appr. at 50%.  Perhaps this is a software problem? Can I give a general reset in some way? (The factory defaults menu option does not help.)

You need to troubleshoot the vertical circuit.

QUESTION NO. P46-7:  How do I remove the cover of a Dell D1025HE 17" monitor?  Who is the manufacturer?

Like many other computer manufacturers (including Packard Bell, Compaq, Gateway, Apple, and more), Dell often uses the same model number for monitors that are different chassis, from different manufacturers.  So be aware that if you post a question for any of these, and did not include the FCC number, any answers you get just might be for the wrong monitor chassis!  To find out the real manufacturer, get the first three characters from the FCC number, and look up the manufacturer on the FCC website at  http//www.fcc.gov/oet/fccid/.

QUESTION NO. P1030-6:   I have a customer with numerous Dell D1526T-HS monitors that need color/geom. adjustments. There are no internal adj. for these settings. The monitor is made by SONY for Dell and my customer spent a couple of hours on the phone w/Dell  only to find out that they no longer support this monitor and referred him to contact SONY. Does anyone out there have the software and cable or info. on where I can get it?

You need the Sony digital alignment software/interface (DAS) package, and Sony will sell you this, but expect to drop roughly $1000, or more, depending on what equipment/interfaces/cabling you already have or can wire up. I think this Dell is a Sony CPD-15SF1 chassis if so, the DAS connector will be a 4-pin connector with round pins near the flyback. If instead the connector is near the power supply and has flat pins, it is a CPD-15SF2. If your client has a lot of units, would they be willing to set you up for doing this service?  A financial/convenience case might be made for an ongoing service.

You may be able to get what you need from Sony parts . You can find a parts supplier through Sony's web site.

QUESTION NO. P1029-4:  Dell D2026T-HS Computer Monitor (seems to be Sony GDM20-E03) FCC-ID AK8GDM20E03, Sony-ID SCC-K18A-A.  Picture is only bright white with about five flyback-lines.  UG2-Voltage is 0V.

It is possible you have a bad high-voltage transformer.  Remove the crt pcb from the crt, turn the set on and recheck the ug-2 voltage.  If you still have no voltage the high-voltage transformer is bad, if you do have voltage it may be a shorted crt.

Just solved this exact problem on my Sony GDM-20E01 FCCAK8GDM20E01 SCC-G96A-A; On CRT board, there is one 3.15A solder-in fuse marked "SOC 315"; I replaced it and got all video-drive back; my prob was caused by accidental shorting of a B+ line while troubleshooting another problem.

QUESTION NO. P1028-6:  Repairing a Dell P1728U found a bad scr but the number will not cross to ecg.  The location  is Q524 and the number on the part is J307.

The J307 is a 2SJ307 and are available from DALBINI 800-325-2264.

J307 is 2SJ307, a 250-Volt, P-channel MOSFET, not an SCR. You can get one from MCM (800-543-4330) or B & D Enterprises (800-458-6053).

QUESTION NO. P108-8:  I am working on a Dell D1728-L5, Video comes up Dim (Flyback OK).  Have checked caps, LM1203. I do not have pin out for Sencore CR70.   If not tube, can someone help?

If you have a CR70, you use socket 3, video 2, bias 100v, filiment 6.3v.

QUESTION NO. P929-3:  I have a 1993 Dell Vi1428U monitor with a fast flashing power led, no high voltage. Speed of pulsing is similar to an unset VCR clock display.   Monitor looks very clean, no burnt components, no cracks on board. Any idea? Power supply?

Listen carefully to the power supply. If it is ticking or chirping, suspect the HOT. If not, check the video connector pins (PC end).  A bent pin(s) that disables sync. signal(s) will place the monitor in power save mode if it is so equipped.

QUESTION NO. P720-6:  I have a Dell Model D1726S-HS that all colors have faded, red is real light pink.  Focus and brightness looks good. Customer said this has progressed slowly.

You should test the tube, preferably with the Sencore beamrite 7000 which checks low level tracking. This test when it fails indicates a "leaky" tube which affects contrast and colors - NO way to fix this problem.

QUESTION NO. P617-10: I have a Dell P1728U monitor here that had a shorted diode (D954). After replacing the diode, the vert IC blew, and I cano't read the number. I suspect that the vert IC was shorted causing the diode to go.. With the vert. IC taken out, the monitor comes up but the LEDs on the contrast and brightness controls flash and the vert. size led is on solid. Can anyone tell me what the part # of the vertical IC (IC401) is?

IC401 is a TDA2006

QUESTION NO. P61-6: I have a Dell D1528LS with no raster, HV is 26Kv, Heater is 6.3, but G1 is about 20V more negative than it should be after doing comparison to a working unit. It appears that the processor could be holding the tube

cutoff.

If this Dell 1528LS is a Lite-On unit, with the Zilog Z0861404PSC processor, that IC is known to give problems, and shutdown to black is one possible symptom. Sometimes freezespray or heating can reveal this IC as a culprit. These IC's have a number stamped on the chip ("Zilog xxxx") indicating the programmed version. So a replacement Zilog (~$20) must be compatible with that version, or you won't have access to control functions like pincushion adjust, or won't sync, etc. Try LJ Enterprises (800-627-8755) or Partronics (800-232-3055) for help on this aspect.

QUESTION NO. P330-8: Dell Mdl D1727S-HS SVGA monitor, horizontal problem. FCC ID: A3LCMH737. High voltage comes up but not measured. The image on the screenis only 2" wide from top of the screen to the bottom. The video is all there inside this two inches, ie; you can read some of the characters. The sides of the image are straight not pinned. The dc power supply voltages were checked and are ok. The vertical shift and size seem to change in the image but the horizontal shift and size doesn't change anything. IC201 (uproc) has horz sync going in and out, also the horz size output from the chip is changing the duty cycle. Horz sync is then fed into a sync processor IC401 a TDA9103. When changing the horz shift or size, nothing changes on the horz sync out pin. The output is a 50% duty cycle square wave that doesn't change at all with shift or size adjusted. The collector of Q407 is 400vp-p. I have checked everything in the horz circuit and have changed the TDA9103 but cannot find the problem.

I had a problem on a 17inch identical to yours. I found that the hot was breaking down. When I pulled the old hot out and compared it to a new one it was very obvious using a curve tracer. I hope that helps.

If I read you correctly, the horiz. output of the TDA9103 (pin 20 or 21) is pinned at its maximal duty cycle (50 2V gives minimal duty cycle, while 6V gives maximum (50%). Try monitoring the input to pin# 2 and seeing if it is within legal limits, and if this DC control voltage can be varied between these limits. Assuming the TDA9103 is functional, it sounds like that pin is stuck high, and so tracing back from this point should lead to the culprit.

QUESTION NO. P29-8:  Dell D1528 Monitor That flashes the Green to Amber LED when powered up, however it justs keeps doing that and never powers up the screen

Check for a shorted HOT. Something is shorting the B+.

QUESTION NO. P210-4:  Dell VI1428U made by Lite-On, many power supply caps were bad and replaced, Power and high voltage is present but still have no video and monitor is squealing. I have about 10 of these models.

Check the values of R436 resistance and R437 is located near the fly-back. They should be 1M ohm..