Steven Zeuner wrote:
>
> Posting this for a buddy of mine....no really. :)
>
> On power up, there is no spot killer. HV is present, with just an eerie
> glow on screen. You can see that the game is playing as the image moves.
> It's mostly a 1 inch circle.
>
> I capped it for him. Replacing all 6 power transistors. I notice that R100
> was fried when I took it out.
>
> After installing all the parts and powering it up. I can see that R100 will
> smoke again. So the cap kit did not replace the defective part.
>
> Any ideas what could be smoking R100? I did check continuity on all the
> power transistors and there fine.
Most likely there is something shorting out the +28-volt line. It pulls
too much current through Q100, causing R100 to fry. Q100 may be
shorted. With the 28-volt line failing, that will also cause the high
voltage circuitry to not perform properly.
Check all diodes and transisors on the deflection board. The MPSU07 and
MPSU57 transistors love to short out. Also make sure the 28-volt zener
diode at ZD100 isn't shorted, or the 1N914 at D104.
HTH,
Matt J. McCullar
Arlington, TX
---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.
Received on Mon Aug 14 23:15:59 2000
This archive was generated by hypermail 2.1.8 : Thu Jul 31 2003 - 23:01:02 EDT