[AMRadio] Re: 220 v.a.c.

D. Chester k4kyv at charter.net
Sat Sep 1 22:45:59 EDT 2007

> Please, help me be sure I am thinking correctly.  To hook up a 220 vac
> transformer to the main, I need use only the two hot legs, is this 
> correct?
> The third leg is for grounding purposes only, is this correct.

> Rick/K5IAR

That's correct.  Just pull the power off the two hot wires, and leave the 
neutral  floating.

I run 220 volts with neutral to my homebrew transmitter, but everything 
inside is 110v.  I use one side of the line to neutral for the filaments, 
vfo, etc.  The other side powers the modulator and final amp plate supplies. 
That way, if the modulator and final pull down the voltage under  load, the 
voltage at other side will actually rise slightly instead of sagging. 
Better for the filaments to brighten up under modulation, than to  dim down.

NEVER strap the neutral directly to ground anywhere except right at the 
service entrance near the meter and breaker panel.
It is unsafe, a violation of the electrical code, and even if it doesn't 
develop into a hazardous condition right away, it will induce all kinds of 
mysterious hum problems into audio and rf equipment due to the ground loop.

Don k4kyv 

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