Re: Tech: G07 help!!!

On Feb 23, 4:25 pm, Qbert247 <qbert...@xxxxxxxxx> wrote:
On Feb 23, 5:19 pm, gamefixer <gamefi...@xxxxxxxxx> wrote:





On Feb 23, 4:07 pm, Qbert247 <qbert...@xxxxxxxxx> wrote:

On Feb 23, 5:02 pm, gamefixer <gamefi...@xxxxxxxxx> wrote:

On Feb 23, 3:46 pm, Qbert247 <qbert...@xxxxxxxxx> wrote:

I am working on a G07 that I recapped and replaced the flyback and HOT
on. It was running fine for about 5 min. while I was adjusting it. I
happened to adjust the wrong pot on the back, and I accidentally
turned the horizontal frequency all the way down. After doing that,
the "magic smoke" was let out of something(I did not see what it was)
and the fuse F902 blew. I replaced that fuse. After turning it on
again, F901 blew this time. The HOT is ok and the flyback is new. All
of the caps are confirmed to be installed correctly. Now what do I
check?

Typically when 901 blows its the HOT or the Flyback (or both). You
might need to remove the wires from the HOT to get an actual reading
off of it though. Going to far with the horizontal frequency pot could
blow the HOT without too much effort. And I've also seen new flybacks
fail within a short period of time. We can thank "Made in China" for
that blunder.

BTW, now that 901 is blown that big cap on the right side of the board
is going to be charged. Be careful... It can zap you pretty good. If
your going to discharge the thing do it with a screwdriver that you
dont care about.

Matt

Hmm...HOT is good and I don't see any burn marks or cracks on my new
flyback...- Hide quoted text -

- Show quoted text -

Your going to be looking for a large component thats shorted. Could be
that the flyback is internally shorted, bad poly cap, bad diode or
even a bad electrolytic cap. Something large is going to have to be
bad in order for 901 to blow. Is the inside of the fuse black or is it
just lightly blown open?

The fuse is black. I saw a huge blue spark in it.- Hide quoted text -

- Show quoted text -

That indicates that you have a serious current draw there. The only
parts that can do that and not blow up in the process are the HOT, the
Flyback, perhaps the poly caps and maybe a dead short thanks to a
solder bridge or an uncut leg on a cap hitting the metal frame.

Matt
.

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