[TechAssist] Re: JVC TV AV2749S, yoke arcing at CRT neck

  • From: "Teltek3" <teltek3@xxxxxxxxxxxx>
  • To: <techassist@xxxxxxxxxxxxx>
  • Date: Thu, 14 Aug 2003 06:38:39 -0400

Gary;

Make sure it clean, cover the spot with a piece of scotch tape, use some
nail polish before you put the other yoke on. I don't think that physically
it will be a spot to worry about.

-Ed-
Ed Gaidies
Tel-Tek Electronics
Ontario-Canada
teltek3@xxxxxxxxxxxx
----- Original Message ----- 
From: "Gary McCartney" <gary@xxxxxxxxxxx>
To: <techassist@xxxxxxxxxxxxx>
Sent: Thursday, August 14, 2003 1:16 AM
Subject: [TechAssist] JVC TV AV2749S, yoke arcing at CRT neck


> I have this JVC TV  model AV2749S in the shop and I have found that the
> yoke is shorted where it wraps around the neck of the CRT, causing a
> black burn mark on the glass. I took a knife and scraped it off but
> there is a slight crater in the glass now, maybe 1/64 of an inch or so
> deep. Is this a weak spot from now on, meaning that this spot will be
> suseptable to more arcing in the future or worse yet, a crack in the
> neck? Can I apply some epoxy to the spot to give it insulation, or
> should this tube be scrapped? I have a used yoke which looks to be in
> great shape which I can use in the set so I hate to tell the customer it
> is garbage.
>
>
> Here is a photo of the mentioned spot on the glass:
>
> http://www.number63.ca/tube-neck.jpg
>
>
>
> How I found the bad yoke:
>
> The set came in with F902, 1.25 Amp fuse open. I couldn't find any
> defective parts so I installed a new fuse in case that was the only
> problem. Pressed power button and saw LED blink and that was all- the
> fuse was open again. Next, I looked up tips and found one that mentioned
> the yoke as a possibility, so I pulled the CRT board and the yoke
> connectors. The LED came on and stayed. Then I reconnected the hor.
> winding and put a new fuse in. Had to use 1.5A instead of 1.25. I used a
> variac set at 90VAC and plugged it in. The LED came on and I heard the
> arcing and saw smoke coming from the yoke/ CRT neck.
>
>
> Thanks for any help.
> -- 
>
>
>
>
> Gary McCartney
>
> McCartney Electronics
> Guelph Ontario Canada
> Est. 1984
> email: gary (at) number63.ca
>
>
****************************************************************************
*
> 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: