[GreenKeys] Re: polar loops

[Don Robert House]

At this late date the older polar relays are becoming scarce.  The 
last polar relay in high volume use was th Weco 314 mercury wetted 
relay.  Many of these relays are still available and have the 
advantage of not having to be adjusted.

Don




At 9:46 PM -0400 06/16/2004, WA5CAB at cs.com wrote:
>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
><http://www.wa5cab.com> (Web Store)
><wa5cab at cs.com> (Primary email)
><wa5cab at houston.rr.com> (Backup email)
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Don R. House
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