On Wed, 12 Aug 2009, Philip Lord wrote:

> I was just about to say that Pin2 is connected to one of the red leads that 
> goes to the capacitor, therefore with the red leads disconnected there would 
> be 0V at pin2, but instead I decided to test it anyway...I got 0.5VDC!!!! 
> Then I realized what is happening:
>
> When I disconnect the two red leads from the capacitor, but still have the 
> two leads connected together the voltage reads 0.5VDC at pin4 and pin2. When 
> the red leads are disconnected from the capacitor, and also disconnected from 
> each other I get just over 8VDC at pin4, and 0VDC at pin2 (as expected).
>
> ...as for a glow from the monitor filliment, I had to turn off all the lights 
> to see it, but yes indeed, there is a glow.

This is good!  This means that the transformer, the big filter capacitor, 
and CR1 and CR2 are all good.

The problem is localized to CR3, C11, C12, C13, VR3, VR4, VR5, or VR6. 
One or more of those is bad.  The prime suspect is CR3.  If it was 
working, you should see 8V on pin 2.  These diodes get hot when operating. 
If it is cold, it is probably open.

Now would be a good time to remove the circuit board.  Small things, like 
paper clips, sometimes get trapped under there, and short things out.
The screw on the left rear of the board is a ground to the chasis.  The 
others should not contact any circuits.

wlevak@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org

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