Quote:
Originally Posted by Rod Beauvex
How does that work in Solid State?
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This is a most the time answer, in general.........
A cold chassis uses a big, heavy, expensive power transformer
OR a more complex switching supply with a small transformer.
The AC ground is separated or isolated from the main chassis ground.
A hot chassis one side of the chassis ground goes to one side of
the AC line. So if plugged in backwards the metal ground of the
chassis has 120 VAC on it. Sets with bridge rectifires are hot either way.
Thats why you have polarized plugs, plastic insulated knobs & shafts cardboard insulators, antenna isolation etc.
Its cheaper to build a hot chassis. When video & audio ins & outs
became popular sets switched to switching supplies. They
cost more than a hot chassis but less than a power transformer.
You need a cold chassis to hook things together, including test
equipment.
Most small sets up til the mid 80's were hot. Most high end sets
& consoles were cold with power transformers til abt 1980.
The more you spent the more likely you got a cold set.
More if you need it.........
73 Zeno
