[TechAssist] Re: SONY KV-27TS32
- From: "Gemini Computer & TV" <geminitv@xxxxxxxxxxxxxxxx>
- To: <techassist@xxxxxxxxxxxxx>
- Date: Tue, 1 Jul 2003 06:33:09 -0400
Many people have already told you to resolder the horizontal driver
transformer which should be standard when working on any of these,
regardless of the complaint. Having said that and if it still shorts the
output (and makes a "big sound" as you described), I would replace C525 off
the horizontal driver transformer and check the horizontal driver transistor
Q502 (2SC2688-LK, Sony part number 8-729-119-80). If you still have the
problem after that, I would suspect the flyback. The service manual is
available for download in the members area.
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@xxxxxxxxxxxxxxxx
geminitv@xxxxxxx
www.geminicomputertvsecurityalarms.com
----- Original Message -----
From: "Peter oliver" <oliver_peter1@xxxxxxxxxxx>
To: <techassist@xxxxxxxxxxxxx>
Sent: Monday, June 30, 2003 11:14 PM
Subject: [TechAssist] Re: SONY KV-27TS32
> Definately an odd one as Lenoard said it is usually one or the other.
Sony's
> litrature seems to indicate (if I read it correctly) that the VDR's
primary
> purpose is to protect the transformers from over voltage when the chopper
> transistors fail. Hence VDR standing for voltage dependant resistor,
> Essentialy a MOV (metal oxide varistor) that only conducts after a certian
> voltage threshold is reached although in that set they may be using it to
> control the firing of the start up transformer. I have seen tips for, but
> never have had to (fortunatly), replacment of some of the small ceramic
> caps in the circuit- possiblly they could be altering the waveform and
> causing a spike or wave form anonomoly or as was proposed the FBT could
have
> an internitnat thermal fault but hypothetically it should have a
propensity
> to kill the HOT again. Another possibility would be a bad batch of
parts???.
> One other off the wall thought that came to me would be to check the
> vertical IC connections in the remote possibity that the connections are
> poor sending an irregular sync pulse into the Horz or Pin timming. PC
board
> cracks?
>
> Peter Oliver
> Tucson Radio TV
>
>
> From: "Leonard Caillouet" <lcaillo@xxxxxxxxxxxx>
> Reply-To: techassist@xxxxxxxxxxxxx
> To: <techassist@xxxxxxxxxxxxx>
> Subject: [TechAssist] Re: SONY KV-27TS32
> Date: Mon, 30 Jun 2003 21:49:29 -0400
>
> I fix these all the time and rarely find a bad VDR, especially when the
HOTs
> are bad. Occasionally there is a bad cap in the primary of the supply,
and
> all of them should be checked. The diodes should be lifted and checked
out
> of circuit as well if you are having repeat failures. Verify that the
duty
> cycle of Q601 and Q602 is 50% +/- a couple of percent when starting it up
> very slowly.
>
> Are you sure that VDR601 was bad? If you checked it in circuit b/f you
> removed the shorted transistors it would have read short. If the HOT was
> the cause of the PS failure, the VDRs are usually OK and the root cause of
> the problem is usually in the H drive circuit.
>
> Like everyone has said, make sure that you resolder the HDT well.
>
> Leonard Caillouet
> Electronics World
> Gainesville, FL
>
> ----- Original Message -----
> From: "Intrepid Video Support" <support@xxxxxxxxxxxxxxxxxx>
> To: <techassist@xxxxxxxxxxxxx>
> Sent: Monday, June 30, 2003 9:04 PM
> Subject: [TechAssist] Re: SONY KV-27TS32
>
>
> > Medi,
> > I've been told all the VDR's should be replaced. At their low price, it
> shouldn't break you, but maybe add
> > reliability.
> >
> > Jeff Dougherty
> > Intrepid Video TV/VCR
> > 263 S Front St
> > Steelton PA 17113
> > fax...717-564-4952
> > www.intrepid-video.com www.tech-repair.net
> >
> > ----- Original Message -----
> > From: "Nova Service Center" <techassist@xxxxxxxxxx>
> > To: <techassist@xxxxxxxxxxxxx>
> > Sent: Monday, June 30, 2003 4:32 PM
> > Subject: [TechAssist] SONY KV-27TS32
> >
> >
> > Hi Everyone
> > The customer complaint was that the Sony TV ( Model # KV-27TS32 ) was
> dead
> . I found 2 regulators (
> > 2sc4834 ) and horizontal output transistor ( 2sc4927 ) were short. Also
> .1
> ohm resistor was open and VDR
> > 601 was bad. replaced all tv turned on and worked for 10 minutes. The a
> big sound and all the parts except
> > VDR 601 went bad again. The VDR 602 and 603 looks good.I don't know
what
> I
> am missing . Any suggestion
> > would be appreciated.
> > Nova service Center
> > 240-632-2994
> > Medi
> >
>
****************************************************************************
> *
> > CHECK OUT THE NEW CHATROOM! Just login and click on chat!
> > http://www.tech-assist.org/secure/tip/main.htm
> > 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/
> >
> >
> >
> >
>
****************************************************************************
> *
> > CHECK OUT THE NEW CHATROOM! Just login and click on chat!
> > http://www.tech-assist.org/secure/tip/main.htm
> > 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/
>
>
>
****************************************************************************
*
> CHECK OUT THE NEW CHATROOM! Just login and click on chat!
> http://www.tech-assist.org/secure/tip/main.htm
> 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/
>
> _________________________________________________________________
> STOP MORE SPAM with the new MSN 8 and get 2 months FREE*
> http://join.msn.com/?page=features/junkmail
>
>
****************************************************************************
*
> CHECK OUT THE NEW CHATROOM! Just login and click on chat!
> http://www.tech-assist.org/secure/tip/main.htm
> 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/
>
*****************************************************************************
CHECK OUT THE NEW CHATROOM! Just login and click on chat!
http://www.tech-assist.org/secure/tip/main.htm
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:
