[TechAssist] Re: Sony KV32XBR96S (repeated audio amp IC failure)

Off the top of my head.....looks like you're replacing the output and the
output side of the amp.....this is the 2nd time around, right??

Is it possible the input side is shifting DC? Or is it capacitively
coupled??

Sometimes I wish they (Sony) would put the old schematics up on the web.

Damon Brunger

----- Original Message -----
From: "Gemini Computer & TV" <geminitv@xxxxxxxxxxx>
To: <techassist@xxxxxxxxxxxxx>
Sent: Thursday, July 22, 2004 9:19 AM
Subject: [TechAssist] Re: Sony KV32XBR96S (repeated audio amp IC failure)


| Update! Besides the audio amp IC (IC1401) being blown again and replacing
it
| along with D1409, D1410,  D1411, and C1407, I have found the following
| defective components in the power supply and replaced them:
|
| Q603
| Q604
| VDR602
| R623
|
| After replacing these and every electrolytic on the "G" (power supply)
| board, when plugging in the set the relay starts to chatter repeatedly and
| Q603 and Q604 get very hot immediately and shortly thereafter short again
| (even with connector G5 disconneted for audio amp B+). this time however,
| R623 remains normal. I can't seem to locate why and I am spending far too
| much time on this set and the customer is very anxious to get it back. I
had
| previously replaced C662 and C668 but as I indicated, all electrolytics
have
| been replaced (again for some of them). Anyone have some sugestions?
|
| Bob Waterman, CET® #RI-28
| Master Technician License #9109
| Service Manager / Parts Manager
| Gemini Computer, TV, & Security Alarms
| (508)695-7302
| (508)695-7769 FAX
| geminitv@xxxxxxxxxxx
| geminitv@xxxxxxx
| www.geminicomputertvsecurityalarms.com
|
|
| ----- Original Message -----
| From: "Gemini Computer & TV" <geminitv@xxxxxxxxxxx>
| To: "Techassist" <techassist@xxxxxxxxxxxxx>
| Sent: Monday, June 28, 2004 8:24 AM
| Subject: [TechAssist] Sony KV32XBR96S (repeated audio amp IC failure)
|
|
| > I have a customer (who is an electronics engineer) with a Sony
KV32XBR96S
| > who brought in his set (as he lives outside my in-home service area)
back
| in
| > January for a dead set condition. I had found the front audio amp IC
| > (IC1401) blown with a hole in it. There were also other damaged
components
| > as well that were replaced with Sony originals. Here is a list of those
| > parts:
| > IC1401
| > IC1501
| > D1409
| > D1410
| > D1411
| > C661
| > C662
| > C668
| > VDR602
| > R623
| >
| > Everything was fine until the beginning of June when the customer once
| again
| > brought it in for a dead set condition again. This time I found and
| replaced
| > the following components with Sony originals:
| > IC1401
| > D1409
| > D1410
| > D1411
| >
| > I completed the repair on Friday, 06/18/2004 and let the set run
| continously
| > around the clock until he picked it up on Thursday, 06/24/2004. I had
| > informed the customer that IC1401 once again had a hole blown in it and
| had
| > him check the external speaker wire connections to make sure that none
had
| > excessive length of exposed bare copper at either end when he returned
| home.
| > The set ran great Thursday, Friday, and part of Saturday but then the
| > customer states he lost audio for about 15 minutes, then lost the
picture,
| > smelled burning, and the set returned to it's same old dead set
condition.
| I
| > just got off the phone with him and explained that it sounds like that
| > IC1401 may have blown again but I am at a loss to explain the reason for
a
| > repeated failure and that I would pose this question to my fellow
| > technicians on the various email forums to which I am a member. So now
let
| > me request your collective ideas!
| >
| > Bob Waterman, CET® #RI-28
| > Master Technician License #9109
| > Service Manager / Parts Manager
| > Gemini Computer, TV, & Security Alarms
| > (508)695-7302
| > (508)695-7769 FAX
| > geminitv@xxxxxxxxxxx
| > geminitv@xxxxxxx
| > www.geminicomputertvsecurityalarms.com
| >
| >
| >
|
> --------------------------------------------------------------------------
| ---
| > Lost Password:
| > http://www.tech-assist.org  and select "Login Problems?".
| > Email Archives:
| > http://www.freelists.org/archives/techassist/
| >
|
|
|
| --------------------------------------------------------------------------
---
| Lost Password:
| http://www.tech-assist.org  and select "Login Problems?".
| Email Archives:
| http://www.freelists.org/archives/techassist/
|


-----------------------------------------------------------------------------
Lost Password:
http://www.tech-assist.org  and select "Login Problems?".
Email Archives:
http://www.freelists.org/archives/techassist/

Other related posts: