[Heath] HP-23 power supplies - an idea and some questions.

Kenneth G. Gordon kgordon2006 at frontier.com
Sun Feb 4 20:33:16 EST 2018


On 4 Feb 2018 at 15:54, Mike Fitzgerald wrote:

> Ken....A lot of trouble for a few more watts out of the 6146's that no
> one can hear anyway....I have made numerous tests asking receiving
> stations if they can hear any differende when I QRO from 100  to 150
> watts. Not one said they heard any appreciable difference...Just sayin"....
> 
> Mike AA7WU

You are absolutely correct, of course. 

In fact, in order to increase the signal level at the receiver enough to hear a difference, one 
must double the output power of the transmitter. 100 watts to 200 watts for 1 db difference 
at the receiver.

1 entire S unit (or 6 db, i.e. a power ratio of 4) increase at the receiver requires increasing 
transmitter output power from 100 watts to 400 watts. Then another S unit above that 
requires 1600 watts. No thanks.

I am not concerned about power output here: to my way of thinking, the lower voltage simply 
"isn't right.".

If it was not important, why did Heathkit change the AC voltage from 268 to 282?

Are there deleterious effects due to the lower voltage OTHER THAN power output? I 
suspect so. 

Screen-grid issues come to mind.

But none of the above concerns me.

So, I still have not gotten an opinion or an answer to my question: is it likely that the 410 
VDC across the 12.6 V winding of the added transformer is too much, or is it acceptable?

If no one knows, I believe I'll try it to see. Empirical evidence is always good.

Ken W7EKB

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