bvamunds
Member
Last Activity: 06-27-2024, 08:42 AM
Joined: 06-16-2015
Location: Mounds View MN
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John, glad you got this worked out and for adding the actual board designations. I'm sure you've made it much easier for future repairs. Cheers, BrianA_MN. -
John, sorry about the delay in responding. I pretty much relied on the repair from a site ccl-la.com, which isn't online now, but I give them credit for creating the original repair.
Check the picture for which capacitor you are trying to repair. The capacitors you need to replace are circled in the picture attached. Use solder braid and remove the bad caps and solder in the replacement caps. Be sure to replace them in the proper polarity, you will see a stripe on the side. The stripe is the negative lead. Just reinsert the new caps with the stripe going the same direction as the old ones...Leave a comment:
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Re: Westinghouse 22w3 DAC 19M009
Thanks CapLeaker, I was looking at the 19M008 schematic and see that these caps are involved in the 19V circuit which feeds the hi-voltage circuit for the CCFL's and also with the 13.8 v supply which feeds the video card. One of them is in parallel with 2 1000Uf 25v caps. The one in the hi-voltage circuit actually is controlling the voltage going into the P605's, which might be why they look so overheated. None of the caps look exploded or bulged, but I just thought that age may have taken its toll and they are cheap enough to simply order, and the...Leave a comment:
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Re: Westinghouse 22w3 DAC 19M009
So I ordered replacement caps from Digi-Key for the ones not previously replaced. I didn't want to tear down the monitor so relied on a listing from another site of the size for the caps and the Delta DAC 19M008 schematic parts list. The DAC 19M008 was built with 220uf 25v caps for c200, ce101 and ce108. But the same capacitors on the DAC 19M009 are all 330uf 25v as found when I removed the board.
So I need a little help. Can I use the 220uf or do I need to re-order to the 330uf caps?
These caps are all part of the power supply,...Leave a comment:
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Re: Westinghouse 22w3 DAC 19M009
The auto button has been used many times and it doesn't affect the image position.Leave a comment:
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Re: Westinghouse 22w3 DAC 19M009
I did find a cracked bulb on the upper, which was causing the screen to blank as if it was two seconds to black. Interesting that it was still lighting with a lower voltage. I order replacement bulbs from CCFL Warehouse. Actually found the correct bulb with leads in Closeout section. I replaced the two upper bulbs and now the top is brighter than the bottom! Probably means that the lower bulbs are starting to fail also, so I'll replace them next.
I'm also seeing a bright spot in the corners for the new bulbs, can that be the result...Leave a comment:
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Re: Westinghouse 22w3 DAC 19M009
Thanks for the clarification. I too was checking the DAC-19m008 schematic [CODE]http://monitor.espec.ws/files/delta_dac-19m008_198.pdf[/CODE] (which is closest that I can find on Internet to the DAC-19m009) and indeed on the page 6 schematic shows the Vadj input and page 3 describes the voltages for ignition and low and high brightness. Thanks again. Cheers. BrianCode:Re: Westinghouse 22w3 DAC 19M009 Thanks for the clarification. I too was checking the DAC-19m008 schematic [CODE]http://monitor.espec.ws/files/delta_dac-19m008_198.pdf[/CODE]
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Re: Westinghouse 22w3 DAC 19M009
R_J, thanks for the information, although it has confused me. CapLeaker's recommendation was to lower the brightness and testing seem to prove it prevented the CCFL's from shutdown. Doesn't the brightness control the high voltage sent to the CCFL's, otherwise, why would turning down the brightness affect the time to black? Also it certainly seemed that when I turn up the brightness, the spare lamp set became brighter to my observation. So what is causing the CCFL power circuit to shutdown when brightness is set higher than 70/100? Just want to learn...Leave a comment:
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Re: Westinghouse 22w3 DAC 19M009
So in this monitor it appears a CCFL set is failing after further testing. The failing unit is probably the top set because the screen is not as bright on top. I had a spare old twin lamp set, which I plugged in to replace the top set. I then turned up the brightness to 90/100 and the monitor stayed on in excess of two hours. The interesting thing is if I turn the brightness down to 30/100 and the contrast up to 90/100 the lamps will still stay on in excess of two hours also. My wife tends to have her monitors blank-out after one hour.
...Last edited by bvamunds; 01-07-2019, 01:00 PM.Leave a comment:
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Re: Westinghouse LCM-22w3 DAC 19M009
This is an LCD screen with 4 CCFL's. It is a great suggestion. Sorry I forgot to test with the flashlight. It is now tested and indeed it is only the backlights which are going out, not the whole power. I can see the image when shinning a LED flashlight into the screen and moving it around I can see the image is present.
If I change the brightness to nearly off, then the backlights stay on longer. Now I'm not sure if that eliminates the CCFL's as being the culprit, or if it simply means that one or more is starting to fail...Leave a comment:
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Re: Westinghouse 22w3 DAC 19M009
Do this to determine what? In other words, what does this test? I'd like to learn. BTW - Happy New Year, I'm surprised anyone is on the board tonight! Cheers....Last edited by bvamunds; 12-31-2018, 06:54 PM.Leave a comment:
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Westinghouse 22w3 DAC 19M009
There are a few threads on the forum which talk about bad caps in the 19M009. Initial issue in July 2015 was a bad rectifier which was replaced along with the main 120uF 400V cap. Since C200 and CE103 were questionable bulging they were also replaced with Nicicon's from Digikey in July 2015.
In July 2018 the monitor stated going black after about 3 to 5 MINUTES. There is also a momentary buzzing/chirping sound when the monitor first starts until an image is displayed and when it goes black. I've opened the unit again and pulled the DAC. There are no obvious bad caps. Notice the... -
Re: HP f1703 Monitor Blackoutafter 2 seconds, but reappears with each insert of VGA
Thanks again budm for your advice.Leave a comment:
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[SOLVED] Re: HP f1703 Monitor Blackoutafter 2 seconds
Tonight I decided to diagnose the problem a little more in depth. With schematic in hand I sought to trace the power from input through to CCFL's. The input voltage from the PSU was 15 VDC rather than the 12 VDC rating on the PSU. Now, an early suggestion in this thread was to check the external PSU for proper voltage and stability. At that time I checked voltage and found 13.8 VDC and thought OK this is strong but typical of PSU's rated for 12 VDC. I didn't check that the amperage output matched the label on back of monitor....Last edited by bvamunds; 07-05-2016, 10:17 PM.Leave a comment:
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Re: HP f1703 Monitor Blackoutafter 2 seconds, but reappears with each insert of VGA
Finally back to fixing this monitor. In the meantime I've been fixing the Westinghouse and Dell 1908FPc which had bad main supply capacitor and bad CCFL respectively. To review what has been done so far, CCFL's have tested good with a different known good inverter. The transistors and poly caps feeding the transformers have been replaced. The transformers ohm out equally on the secondaries.
I haven't been able to test the sense circuit yet, because the test points are on the bottom...Leave a comment:
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Re: HP f1703 Monitor Blackoutafter 2 seconds, but reappears with each insert of VGA
Finally got back to this. I ordered replacement .15uF polycaps, and 2sc5707 transistors to replace the 2sc5706 from Digikey (great folks to work with and fast shipping). Put them in the circuit last night. Unforunately I'm getting the same results, ie 1 seconds to black.
BTW, the old caps tested at 150.02 nF each. All four of the old sc5706 read "35Meg ohms when measured B(+) to C(-) and E(-) but "OL" or infinite in all other matchings, does that mean they are good or...Leave a comment:
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Re: HP f1703 Monitor Blackoutafter 2 seconds, but reappears with each insert of VGA
budm -> thanks for the instructions. I'll also checkout your signature tutorials to better understand circuits. I have a HP F1503 monitor, are its internal similar enough to test the CCFL's or even temp swap to this F1703 logic? Thanks
I also have a Dac-19M009 that has died (no power) but will start separate thread for it. As a teenager I use to enjoy hobby projects like these, then life with college, married, kids and my hobby became software and voice/data networking. Now I'm retired...Leave a comment:
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Re: HP f1703 Monitor Blackoutafter 2 seconds, but reappears with each insert of VGA
budm, no the CCFL's were clean and had little discoloration at then ends. I pulled them primarily to inspect for a cold soldering joint, but they were solid connections. Thanks for the advice and alternate part number. Do I need to test them disconnected even though they measure equally in circuit?Leave a comment:
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Re: HP f1703 Monitor Blackoutafter 2 seconds, but reappears with each insert of VGA
Do I need to test the caps and transistors out of circuit? I'm asking because I'm getting the same reading on all four transistors. These little guys are NPN type according to the schematic, they measure B(+)->C(-)= .178; B(+)->E(-)= .506, C(+)-.E(-)=.507. Each one matches exactly in measurement. The emitter lead goes to power ground. Base and Collector both go to separate loops of the high voltage transformer coil. The Base leads each act as one end of the loop, but there are two parallel...Leave a comment:
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Re: HP f1703 Monitor Blackoutafter 2 seconds, but reappears with each insert of VGA
Thanks for the suggestions. Yes the purple caps are Hermei, the black two say "TL" and the polyester ones are PMG. The external power supply is good and provides a solid 15VDC.
Here is an interesting issue, the HP linked document for this monitor has the parts listed per board. The only thing is the inverter board model listed is IDPC7425A1 and the board in this monitor is IDPC7426A1, and the caps seem to be slightly different. For example the two large polyester caps are...Leave a comment:
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