Main > Monitor/Video Forum
Help with a (generic?) H-12 Universal Chassis
kyle__:
Oh. OK. So, is that something you can tell from looking at it, or the model? How does one figure that out?
Edit, also ordered this from Jameco: https://www.jameco.com/z/ITR300-Power-Transformer-Isolation-120VAC-120VAC-300VA_181315.html
Ken Layton:
I can tell by looking at the chassis. There would have been a large yellow transformer in the power supply section. That would have been part of a switching regulator power supply. Since it didn't have that transformer, this is a chassis that needs an isolation transformer.
By the way the transformer you ordered is a bit overkill for the common monitors. Here is what most games requiring isolation use:
http://www.arcadeshop.com/i/1346/monitor-isolation-transformer.htm
kyle__:
So .... if I plug in the chassis to the isolation transformer, and plug it in, it blows the fuse on the transformer. Did my plugging this in without an iso transofrmer kill it; is it a lemon of a board; or do I just have it hooked up backassward?
grantspain:
check the diodes in the bridge circuit and the regulator
kyle__:
I tested all the diodes I could identify. They seem fine.
I don't know if it's related to what's happening, but what are these circled in white here?
The short wires jumpered to one of two pins.