Isolation transformer voltage to my monitor?

What kind of monitor? Most isolation transformers should have a 1:1 ratio, 115v in equals 115v out.

If it is a Nintendo or some of the early Sega color games you should be seeing closer to 100v.
 
It's a Sega monitor from a Zaxxon, I am getting 107v, is that enough to power up the monitor?


It should be enough to power up any monitor. When you say a Sega monitor, what do you mean? Have you identified the monitor type? Is the power connection a Molex 2 position connector or is it a jones plug (similar to a lamp power cord)?
 
Molex 2, not a power cord type, I have a Sega Frogger that has a power plug like you described. A decal on the back of the monitor says:
Model No.19K4675
120v 60Hz 70 w max
Well Gardner Electronics Corp.
 
Well it's not coming up from the 107v, should I supply 120 volts to it from the ac from the switching power supply?
 
I did notice that on the isolation transformer that it has posts for 100v and 120v, it is currently wired to the 100v, can I switch those wires over to 120v for my monitor?
 
Are those the input or the output wires?

Test the lugs with a meter. If the output is closer to 120v but doesn't exceed 130v you should be able to safely shift the monitor input power but it will not fix your problem.
 
I looked for the B+ (VR501) and also the emitter (VR502) to make the B+ adjustment as you suggested but I can't find anything labeled VR01 or VR502, I will include some pics of the chassis so you can possibly see something that I do not.
 

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In your last picture there is a board that is standing up on the left side of the pic against the metal frame. This has nearly all of the B+ regulation components.

TP91 should read the B+, pin 2 of this small daughter board is another area you can find the voltage.
 
If I remember correctly, the pot for adjustment is also on the daughter card. It is most likely covered in epoxy, though.

It is much more likely that you'll find that the B+ is extremely high, say 150v or more. This points to a failure in the B+ circuit so you'll have to test the components in the circuit. Start with the voltage regulator. Dokert has a good write up here for testing transistors. He uses a G07 for examples but the concept is the same.

http://forums.arcade-museum.com/showthread.php?t=126760&highlight=test
 
I tested the hot and the voltage regulator as shown in the pictures and my meter read a 4 digit number and then went to 1 on both the hot and the regulator. The thread was a little misleading, are they good or are they bad?
 
Does a 1 on your meter display when the leads are removed or does it display when they are shorted (held together)? Either way the results do not look good. However, you should test your meter's battery. If the battery is failing it can give you erroneous results.
 
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