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Maybe we need to learn more about PIN Diodes?
 
73/K5GW
 
In a message dated 3/30/2008 7:01:28 A.M. Central Daylight Time,  
hmandel@barantelecom.com writes:
When I  first saw a Jennings RJ-1, and
compared it to the open frame relay  my
'220 was using, it was astonishing.
That was because vacuum  relays are
good for isolation.
However RJ-1's are virtually  useless
for a decent QRO rig above 20 meters
and that's because the RF  ampacity
diminishes so rapidly with frequency
change.
On bigger  tube rigs it was necessary to 
graduate to an RJ-2, but remember,  those
vacuum relays only carry 12 amps at 32MHz.
So then there's the  Jennings RF-10C.
The problem with getting vacuum relays with
enough  contact gusto is they slow down because
of mass and inertia. The RF-10C is  not too good
at 50WPM as you can imagine.
So it's a toss-up: You get  a relay capable of
high speed QSK and it has poor ampacity and
blows out  frequently, or you get an  elevator
contactor.....
Hal
W4HBM
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