[TechAssist] Re: KV35S36 regs in thermal runaway
- From: "Leonard G. Caillouet" <lcaillo@xxxxxxxxxxxx>
- To: <techassist@xxxxxxxxxxxxx>
- Date: Tue, 23 Sep 2003 10:09:52 -0400
The one that I had with a bad transformer would run for a few minutes and
blow the transistors. They got hot pretty fast. The transformer did not
test bad, but did not measure the same inductance on one of the coils as a
good one that I had. I just got lucky to have one to compare.
Leonard G. Caillouet
Electronics World
Gainesville, FL
352-332-5608
352-332-5668 (fax)
----- Original Message -----
From: "tony saracco" <tcselectronics@xxxxxxxxxxxxxxxx>
To: <techassist@xxxxxxxxxxxxx>
Sent: Tuesday, September 23, 2003 8:33 AM
Subject: [TechAssist] Re: KV35S36 regs in thermal runaway
Thanks for the tips Leonard, I also match up the transistor by the date
code and have went as far as measuring the EB junction on the diode check to
match as closely as possible. I will check the duty cycle next chance I get
to insure 50 %. I get one of these supplies every now and then ( usually on
the 35" TV) that no matter what I change it still will over heat the regs
and self destruct within an hour. you mentioned the transformer in the pws
reading bad, what problem did it cause
( overheating or instant destruction).
Tony Saracco
TCS ELECTRONICS
Elgin , IL 60120
847-695-1928
tcselectronics@xxxxxxxxxxxxxxxx
----- Original Message -----
From: "Leonard G. Caillouet" <lcaillo@xxxxxxxxxxxx>
To: <techassist@xxxxxxxxxxxxx>
Sent: Monday, September 22, 2003 12:25 PM
Subject: [TechAssist] Re: KV35S36 regs in thermal runaway
> Tony,
>
> Check the duty cycle, it should be pretty close to 50%. IF it is not,
look
> to one of the components in the primary or try matching your transistors.
I
> buy them in batches and they seem to match up pretty well but mixing
batches
> can get you in trouble, even with Sony replacements. Generics are fine if
> they are the Shindingen parts and not some copy. I fix dozens of these
> power supplies (using Tritronics generics made by Shindengen just like the
> Sony pars) and never have a recall due to bad transistors. Check all of
the
> caps and diodes out of circuit. Check or replace VDR601, especially if
R622
> is open. I believe that one is a 430v rating.
>
> Look to the secondary, like a problem in the 9v regulator. I just had one
> kill Q601,2 that had a shorted SI3090C (IC641).
>
> I also had one once with a bad T603. It rang good on all windings but I
got
> lucky and had one to compare it to that was reading differently. That was
a
> lightning damaged set and the only convertor that I have seen bad in a
Sony
> PS.
>
> Does it fail if you run the PS unloaded out of the set?
>
> Leonard G. Caillouet
> Electronics World
> Gainesville, FL
> 352-332-5608
> 352-332-5668 (fax)
>
>
>
>
>
> ----- Original Message -----
> From: "tony saracco" <tcselectronics@xxxxxxxxxxxxxxxx>
> To: <techassist@xxxxxxxxxxxxx>
> Sent: Monday, September 22, 2003 12:11 PM
> Subject: [TechAssist] KV35S36 regs in thermal runaway
>
>
> I have changed the .47uf bird tird caps, .22uf blue caps, 2 - .001uf blue
> caps ( basically all caps in primary side of reg circuit) statically check
> all other reg components but Q 601 an 602 still over heat and die after 45
> min. I even tried making heat sinks with no luck there. YES i am using
> generic C4834's but can get away with it most of the time without thermal
> probs. Have tried both P's and M versions.
> any advise or maybe a pws part # if it is still available, Not listed on
> tritronix model part list.
>
> could use the SM if someone wants to Email it to me.
>
> thanks much
>
> Tony Saracco
> TCS ELECTRONICS
> Elgin , IL 60120
> 847-695-1928
> tcselectronics@xxxxxxxxxxxxxxxx
>
****************************************************************************
> *
> Classifieds! Buy or Sell!
> http://sell.tech-assist.org
> The Tech Address Book:
> http://www.tech-assist.org/secure/tip/contact.htm
> Add a Repair Tip Here, or Change/Remove your Email Address:
> http://www.tech-assist.org/secure/tip/main.htm
> Lost Password:
> http://www.tech-assist.org and select "Lost your Login Info?".
> Email Archives:
> //www.freelists.org/archives/techassist/
>
>
>
****************************************************************************
*
> Classifieds! Buy or Sell!
> http://sell.tech-assist.org
> The Tech Address Book:
> http://www.tech-assist.org/secure/tip/contact.htm
> Add a Repair Tip Here, or Change/Remove your Email Address:
> http://www.tech-assist.org/secure/tip/main.htm
> Lost Password:
> http://www.tech-assist.org and select "Lost your Login Info?".
> Email Archives:
> //www.freelists.org/archives/techassist/
>
>
****************************************************************************
*
Classifieds! Buy or Sell!
http://sell.tech-assist.org
The Tech Address Book:
http://www.tech-assist.org/secure/tip/contact.htm
Add a Repair Tip Here, or Change/Remove your Email Address:
http://www.tech-assist.org/secure/tip/main.htm
Lost Password:
http://www.tech-assist.org and select "Lost your Login Info?".
Email Archives:
//www.freelists.org/archives/techassist/
*****************************************************************************
Classifieds! Buy or Sell!
http://sell.tech-assist.org
The Tech Address Book:
http://www.tech-assist.org/secure/tip/contact.htm
Add a Repair Tip Here, or Change/Remove your Email Address:
http://www.tech-assist.org/secure/tip/main.htm
Lost Password:
http://www.tech-assist.org and select "Lost your Login Info?".
Email Archives:
//www.freelists.org/archives/techassist/
Other related posts:
