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  #16  
Old 04-30-2017, 09:52 PM
user181 user181 is offline
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Quote:
Originally Posted by rcaman View Post
the last i got from encompass was junk and went up in a fit of sparks. and encompass would not warranty them i no longer buy ANYTHING from encompass.

Is there another supplier you'd recommend?
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  #17  
Old 05-03-2017, 11:00 AM
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Findm-Keepm Findm-Keepm is offline
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Quote:
Originally Posted by rcaman View Post
the last i got from encompass was junk and went up in a fit of sparks. and encompass would not warranty them i no longer buy ANYTHING from encompass.

248 dollars of parts (mostly 2SC4834s, MX0841s, and one lamp ballast board for aDLP set) from Encompass so far (since 2012/3), and all are genuine, but even genuine parts will fail if the original problem isn't fixed - whatever caused the original part to fail will take out any replacement.

What genuine Sony replacement source do you suggest, or use? Hard to find any Sony parts in North America anymore, much less genuine without going with Encompass - expensive they are, but original and genuine.
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Last edited by Findm-Keepm; 05-03-2017 at 11:01 AM. Reason: 248 vs 348 - correction..
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  #18  
Old 09-26-2017, 12:44 PM
user181 user181 is offline
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I'm following-up on this issue that I originally posted in April (Sony KD-34XBR970, having trouble starting up).

The issue first occurred in April, then again in early August, and yesterday (late September), and each time I was able to resolve things by briefly unplugging AC power to the set.

I have read everything you guys have posted about the MCZ3001DB chips being the likely culprit, and I've also taken note of the fact that there are counterfeits out there to beware of. Way back in April I preemptively purchased some chips from Encompass Parts, as well as proper sockets for them. So, I'm prepared to replace them when the time comes.

However, part of me has a nagging feeling of wanting to be certain this is the correct thing to do.

Are there any measurements or tests I could do (without specialized/proprietary equipment) to verify if the chips are good/bad? Is there a typical separate root-cause for these chips to fail, or is the problem the chips themselves?

Also, since I'm able to get by -- for now -- by power-cycling the set, I'm hesitant to risk making things worse by messing with it. What general advice do you guys have for making such a repair? I'm relatively proficient with soldering/desoldering, but I have never worked on a CRT TV. Do I need to discharge the CRT before proceeding to work on the D board? I'm sure the answer is 'yes,' but I could sure use some guidance on that.

From the service manual for this particular set, it seems that some of the boards can flip or hinge for service access. Is that the case for the D board, or is it best to completely remove the board from the set and do the chip replacements on the bench?

I know I've asked several questions, and I sincerely appreciate your patience and bearing with me.
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  #19  
Old 09-27-2017, 08:56 AM
zeno zeno is offline
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There are 2 power supplies. One is always on & supplies
the micro & on/off relay ( if it has one.). Second one supplies
B+ for horz/HV. Its on/off is via a relay or other method.
You will need a schematic for at least the power supplies
to check them & see if one isnt working.

Use care changing the IC's the board is double sided & you will
probably lift some top etch. If you have very small dikes
you can try nipping off the IC pins & saving the etch. Otherwise
you will need jumpers.

We were a authorized Sony dealer / warranty station at that time.
Never seen a bulletin on the problem & Sony TA changed the subject !
It was common, I had the 30" & went through 3 sets in abt 5 yrs.
Shame of it is the 30 & 34" widescreens were the best CRT sets
ever made pix wise.

good luck Zeno
LFOD !
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