Quantum picture crooked, spot killer flickers...

Hello,

    On my Quantum, I replaced both 12 bit DACs (AM012's) and I'm now getting a
picture that is rather small, and seems to slope diagonally to the lower right
of the screen (remeber that Quantum is a verticle game). In attract mode, the
spot killer still trips when "Quantum" is being drawn on the screen, and the
spot killer seems to flicker occassionally, with the picture flickering as
well (spot killer is starting to kick in, but not quite, thus causing the
picture flicker). I've tried all my board pots, no luck. My picture seems weak
on the X side - my "X-size" pot won't even come close to putting the picture
to the edges of the screen. (The pot is working though, as are all the other
board pots).
     I am using a scope (but not a really good one) that my friend Ed loaned
to me. The picture is readable now, but it's not even close to being playable.
I can put a cross hatch up in test mode, as well as a diagonal grid, but in
attract mode, things start flickering, and I get the spot killer every time
"Quantum" is drawn on the screen. Any ideas on this? Perhaps its the 8-bit
DAC? Please help if you can, I'm stuck on this one. I don't know what the
signals should look like as normal, and becuase I'm getting signals, it's
making it hard to find where the troubles are.
     Also, I'm trying to get the following chips, please help if you can:
Here are the AVG parts that I am trying to get. Pulls are fine (as long as
they work):

UC1495N (4 of these) Atari part # 37-1495 Multiplier integrated curcuit
AM6012 (2 of these) Atari part #137158-002 12-bit DAC
DAC08CN (2 of these) Atari part #137159-001 8-bit DAC
13201-5 (2 of these) Atari part #37-13201 Quad analog switch

Please let me know if you can get these, and what they will cost. I really
appreciate your help!

Thanks Very Much,
Michael Kelley
Received on Mon Oct 5 10:05:09 1998