[GreenKeys] Re: polar loops

[WA5CAB at cs.com]

Simplest solution of all (and most likely the most reliable) would be to just 
use the WE215 or WE255 polar relay that the system was no doubt built to use. 
 You can drive the neutral side with your preferred brand of poison.

If the RT-671/PRC-47 had been delivered with a vibrator in the inverter 
instead of those !@##$% germanium power transistors, mine like all the others would 
still no doubt be working.  But a lightning strike on a phone line took out 
the RT-671 plus almost all of the solid state based gear in the house.  The 
tube and dynamotor based gear in the garage (shack) all still works fine.

In a message dated 6/16/2004 8:24:44 PM Central Daylight Time, 
gil at vauxelectronics.com writes: 
> With an adapter, you could convert a neutral-loop keyer to drive a polar 
> loop.  Something like an H-bridge of transistors comes to mind.  Hafta play 
> with it a bit.
> 
> The loop sense needs no change -- the zener will conduct in forward mode 
> for the other polarity.
> 

Robert & Susan Downs - Houston
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