Re: Tech: Wells Gardner problems

Jeff Hendrix wrote:

>
> 1. The first HV unit thinks the HV is too high and is shutting it self down
> (I can rewire this to by-pass it if I have to)

If the first HV unit is shutting itself down, there's most likely a real
problem in the HV circuit rather than a fault in the over voltage
protection circuit. Bypassing the cutoff circuit seems dangerous
because if you allow the HV to run and the HV is set too high, you'll
risk X-RAY emissions from your tube. I suppose that as long as you are
careful to adjust the HV once you get it running, then you'll be OK.
Though, make sure you have your children before attempting this
maneouver. :-)

>
> 2. I can't get green (I've check to make sure the z signal is getting to
> the socket), Is it possible for one color to be bad in the tube?

Yes. I had a problem like this on a VGA monitor a few years back.

Did you try swapping the old neck board back onto the tube to see if the
red color now works? It's possible that the pins are simply oxidized
and need a good cleaning. Perhaps the wiping action of replacing the
neck board was enough to clean the pin for the red signal. I think you
can pretty much prove that you have a defective neck board if swapping
them again nets only the blue color.

You might just check the pots on the board to make sure they still work
correctly.

Just for grins, make sure that your boardset is actually outputting the
green color signal. Check it with a scope. I've had a Star Wars
problem where the drive transistor failed on one of the colors.

Joel-
Received on Tue Oct 21 09:29:21 1997