Thanks for the tips ! I'll try to open it and redo some soldering on the
POT then. If it doesn't work, I'll fine time to come and visit you Josh :)
Le sam. 25 nov. 2017 à 21:41, Josh Bensadon <jbensadon@xxxxxxxxxxx> a
écrit :
Jeremie,
There's only 1 place that's dangerous, that's the high voltage anode.
I was very scared the first time I grounded one of these, but after doing
it a few times, it's like taking a walk through the park. In fact, walking
through the park is more dangerous, you might get mugged.
The schematic is not very complicated, in fact, it mostly all goes to 1
IC, which is probably working just fine.
That Colour POT is very likely to be the issue, or another signal to this
IC (perhaps the colour burst crystal).
I did some Colour TV repair, long long time ago when all those circuits in
that IC were separate transistors and even tubes! But the most important
thing on that schematic is that they show you the signals at all the test
points. You can track down a problem very quickly... it's just a matter of
finding the test points.
Can you look around to see if you find a PCB parts layout for this board?
It should show you which are the test points on the board. It will make
tracing the problem even faster. Assuming of course you are accepting my
offer to visit my shop.?
Cheers,
Josh
------------------------------
*From:* torontocbm-bounce@xxxxxxxxxxxxx <torontocbm-bounce@xxxxxxxxxxxxx>
on behalf of Jérémie Marsin <jeremie.marsin@xxxxxxxxx>
*Sent:* Saturday, November 25, 2017 8:03 PM
*To:* torontocbm@xxxxxxxxxxxxx
*Subject:* [torontocbm] Re: Commodore 1802 Monitor needs service
Thanks for the tip Rob! I though about the color pot too. Even though I do
a bit of electronic repairs myself as a beginner, I'm always afraid to work
with crt screens, that's why I didn't touch it. I'd rather ask someone
who's advanced in electronics!
Le sam. 25 nov. 2017 04:09, Rob Adlers <robadlers@xxxxxxxxxxx> a écrit :
Sorry for multiple replies. My other thought was a cold solder on the
color pot.
Here's a fruitful thread of things to check.
http://www.lemon64.com/forum/viewtopic.php?t=22590&sid=91e95487c383576e9235b575264426b8
Sent from my BlackBerry - the most secure mobile device - via the Rogers
Network
*From:* robadlers@xxxxxxxxxxx
*Sent:* November 25, 2017 4:02 AM
*To:* torontocbm@xxxxxxxxxxxxx
*Subject:* Re: [torontocbm] Commodore 1802 Monitor needs service
Is this happening with all inputs? I had a sync problem that turned out to
be a faulty cable.
Rob
Sent from my BlackBerry - the most secure mobile device - via the Rogers
Network
*From:* jeremie.marsin@xxxxxxxxx
*Sent:* November 25, 2017 12:03 AM
*To:* torontocbm@xxxxxxxxxxxxx
*Reply-to:* torontocbm@xxxxxxxxxxxxx
*Subject:* [torontocbm] Commodore 1802 Monitor needs service
Hey all,
I've had this monitor in storage for two years now and didn't use it
because it has a very peculiar issue, it's only showing back and white. And
no it's not related to a PAL/NTSC issue or misconfiguration/cable. It's
really b&w. The color potentiometer is the only one that doesn't have any
effect on the image, so maybe it is something related to that.
Anyway, I'm looking for someone that could take a look at it and maybe
even repair it !
I'll be at WoC and can bring it.
Any idea to whom I may talk to ?
Thanks !
Jeremie
