More circuit help required please

Tony Duell ard.p850ug1 at
Sun Jan 8 08:06:45 CST 2017

On Sun, Jan 8, 2017 at 2:00 PM, Adrian Graham
<witchy at> wrote:

> You were right, I'd drawn out R335 wrongly and flipped V333. All the anodes
> go via R312 to the collector of V333 along with R309-R311. Base for V333 is
> the inverted sync output of the MR9735. R322 is 6.8k
> (blue-grey-black-brown). All diodes are 1N4148.

That makes more sense. I am surprised that the anodes of the diodes don't go
to a +ve power line (maybe +12V), though. It could be right as drawn,
but I would
check it.

When you power up, what voltage and/or signal (use a 'scope) do you see on the
anodes of said diodes?


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