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OK, let's take this one question at a time.
<p>Paul Sommers wrote:
<blockquote TYPE=CITE>
<p><font face="Arial"><font color="#0000FF">Gang,</font></font>
<p><font face="Arial"><font color="#0000FF">The sad history of my Breakout
is that the transformer caught on fire about a year ago (smoke everywhere
- the fire brigade actually turned up because I opened all windows and
doors for the smoke to get out).</font></font>
<p><font face="Arial"><font color="#0000FF">I have now replaced the transformer
with two others (one for 110vac and one for 16.5 and 6.3 vac).</font></font>
<br> </blockquote>
At this point we will assume he means the GAME transformer and not the
monitor transformer---only way the voltages make sense.
<blockquote TYPE=CITE>
<br><font face="Arial"><font color="#0000FF">It looks like the board got
spiked because it was working fine to that point - now I have monitor and
board problems that I've got some questions about.</font></font>
<p><font face="Arial"><font color="#0000FF">1. I have replaced all the
lytics on the monitor board, and it made no difference. I'm getting continuous
waves through the picture. I don't believe they are hums bars. Just waves
of greyscale. If you adjust the brightness and contrast to SOLID black
and white - it is almost un-noticable. The waves move across the vertical
screen right to left.</font></font>
<p><font face="Arial"><font color="#0000FF">There are an awful lot of polyester
caps on the board. Very old. Should I replace these or look for something
else.</font></font>
<br> </blockquote>
Leave the monitor alone for now, unless it has the waves while set for
gray with the game board unplugged. Leave polyester capacitors alone
unless you know for a fact they're bad. It's unlikely they are a
problem.
<blockquote TYPE=CITE>
<br><font face="Arial"><font color="#0000FF">The thought has occurred to
me it may be coming from the PCB.</font></font>
<br> </blockquote>
Either that or the power supply.
<blockquote TYPE=CITE>
<br><font face="Arial"><font color="#0000FF">2. There are three caps of
50uf. The schematic lists these are polyester, but these look lytic. It
doesn't look like a repair - or it was done long enough ago all the solder
matches.</font></font>
<p><font face="Arial"><font color="#0000FF">I can't find 50uf caps anywhere
in Australia. How would I go with 47uf. Just how much tolerence do these
things have.</font></font>
<p><font face="Arial"><font color="#0000FF">Should I follow the original
schematic and change them back to poly's.</font></font>
<br> </blockquote>
47 would be fine. Tolerance on electrolytics (unless marked otherwise)
can be as drastic as -20% to +100%. But I doubt these are your problem.
<blockquote TYPE=CITE>
<br><font face="Arial"><font color="#0000FF">3. While we're on caps. The
big 8000uf at 16v that is one the board looks pretty old. But the only
8000uf cap I can get in Australia is 80v and it is a surface mount. What
a pain - not to mention expensive. Can I put a couple of lower value caps
which make up 8000uf in series or parallel instead???</font></font>
<br> </blockquote>
Sure. Or use a 10,000. Or a 20,000! Whatever you can
find. Or just try tightening the terminal screws on the one you have
and see if that helps.
<p>BUT, before we get too carried away with this, I have a question.
Is there ONE hum bar or TWO? Very simple rule here:
<br> ONE hum bar = bad rectifier (or fuseholder in series
with rectifier)
<br> TWO hum bars = filter capacitor problem.
<blockquote TYPE=CITE>
<br><font face="Arial"><font color="#0000FF">4. The paddle is shaky. It's
okay when it is hard right, but as you move it further left you get very
very shaky double and triple images. I'm wondering whether the main 8000uf
cap which does the power filtering could cause this, as the paddle is the
only part of the circuit (except sound... blip) that uses analogue components.
I have replaced the 4016, 555 and the pot with no effect.</font></font>
<br> </blockquote>
Could be ripple doing this.
<blockquote TYPE=CITE>
<br><font face="Arial"><font color="#0000FF">5. I'll work this last one
out eventually.... I have only half a brick in the first column (left hand
side). Just thought someone may have seen this before.</font></font>
<br> </blockquote>
Monitor adjustment? If I remember correctly, Breakout had the monitor
turned so this would be a vertical adjustment. OR that side of monitor
is squashed (ala Nintendo games) due to open electrolytic in power feed
of vertical output stage.
<blockquote TYPE=CITE>
<br><font face="Arial"><font color="#0000FF">Phew! It seems a lot, but
I've brought it back from the dead and started getting tired of working
it out myself. Hopefully someone can help me on one or more.</font></font>
<p><font face="Arial"><font color="#0000FF">Thanks</font></font>
<br><font face="Arial"><font color="#0000FF">MacMan</font></font></blockquote>
<p>--
<br>Windows:
<p>32 bit graphical interface for a
<br>16 bit patch for an
<br>8 bit operating system written for a
<br>4 bit processor by a
<br>2 bit company that can't stand
<br>1 bit of competition.
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Received on Sun Sep 24 19:43:49 2000
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