🚀 go-pugleaf

I too have found that the C24 is a touchy little bastard.  However, when
passing normal video through the device, I am able to make the unit sync up
by turning up R34 to allow a very colorfull picture.  This results in a smaller
color burst level, and fewer things for the TV to have problems locking in on.
I can then lower back down R34 to a normal color level, and the picture usually
stays locked.

Some observations noticed with the oscilloscope:

Pin 8 of IC5 (the chroma chip) outputs garbage when the circuit powers up.
Pin 7 (the clock signal from the 3.58 oscillator associated with C24)
  looses amplitude and lock when I touch C24 (makes sense eh?)
As a result, I get no burst key from the CD22402, and no lockup.
Something else I noted... Pin 9 of the PLL outputs a stable signal at all
times (not surprising for a PLL) but the frequency changes once the circuit
locks up to a slightly higher value.  Keeping this in mind, I have tinkered
with C36 (what I believe to be the initial frequency setter) but have not
found any golden results.

Anyone have any other ideas?  I have also played with the value of C42 by
placing various capacitors in parallel, and even removing it to put in a
smaller fixed value, but no results other than failure to be able to lock up
even with the button pressed.  I believe that the value of the cap is correct,
because the screen scrolls horizontally at a reasonable rate when S1 is
pressed... what else does that leave?

Thinking back now, the deal with adjusting R34 doesn't make all that much
sense as far as the circuit locking up, because it only controls the level
output to the TV, not the levels internal to the circuitry... hummmm....

The technical support number given by the company that sold the kit is
518-854-9280.  Does anyone in that area code care to give the company
a call?  hours are 1:30-4:30 pm EST.

Scott
sb2o@andrew.cmu.edu