Take the BU406D back out. That will prevent any high voltage from
being generated while you run this test:
The key test is that you are getting +30V and -30V DC unregulated
coming into the voltage regulators, and +24V and -24V regulated going
out of the regulators. If you are getting wacko readings at any of
the test points, you have issues you need to clear up before putting
the BU406D back in.
There is a detailed procedure on this in Michael Kelley's excellent
Amplifone HV guide ver 1.2 starting on page 24 (worth 10 times the
price...). The top of page 26 shows where you can easily check the
voltages without shorting something out. Note that it is normal for
the -24V can be as low as -36V if your board has the 5w 50-ohm
resistors at the regulators. If everything tests out, put the BU406D
back in and try it out!
I just rebuilt my Star Wars HV board using this guide and it is
working awesome now. I had several bad components and lots of cold
solder joints that the guide helped me find and fix easily. Make
sure you replace the W1 jumper with a piece of straight wire as the
jumper can test OK but not work under load (mine was bad). You have
around six "W" jumpers on the deflection board as well, so if you're
not getting +30/-30 at the regulators, your deflection board (and
maybe its "W" jumpers) is likely the culprit.
After I turned everything on and got a picture, and since I don't
have a HV probe, instead I measured the anode side of CR3 and set a
DC voltage of 180 using the R7 pot. (If you trace the wintron green
wire you will see the copper trace leads up to CR3. Put your red
probe on the far side of CR3 and black to ground). 180V at this
point corresponds to 19.5K volts at the monitor cap. If memory
serves, decreasing R7 increases the B+ voltage at CR3.
I actually have no idea what I'm talking about - I didn't know what a
solder sucker was a month ago. Just use the guide like I did and
you'll have it working in no time!
Hope this helps!
Jonathan
On Sun, 30 Mar 2003 10:46:25 -0800, Tony Jones wrote:
>4) I've installed a Wintron, new BU406d, new regulators, fuses
>between the
>HV and deflection board -- but I have no history with the
>HV/deflection
>boards. Is there any testing that is recommended before flicking
>the
>power switch?
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Received on Sun Mar 30 11:25:28 2003
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