[R-390] Post to List (Antenna Relay)

[Flowertime01 at wmconnect.com]

I think it best to keep this relay, so terminals are grounded
during break times when transmitting.  Am I wrong, and
is the relay really needed for ham use?   jsullivan

Most fellows using R390 or R390/A for Ham use are also running a transmitter.
The relay gets used for break-in operation. 

Some fellows have TR switches, but these can bleed RF through, so having the 
antenna get grounded is good. Some of the TR switches just swap the antenna 
via relay between trans and receive. Some just cut the receiver signal off by 
driving a tube or transistor into cut off. Some TR switches actually ground the 
break-in circuit on the R390's and use the antenna relay to ground the 
receiver input. Of course in these circuits you cannot also feed the whole 
transmitter output into the R390 input, some other switching action has to occur. 

The receivers offer a single ended coax for input. The better balance input 
is just a Twinax IBM network type cable. The connectors and coax are very 
available. The Receivers also were operated with an adapter from twinax to grounded 
one side and single center conductor coax feed. Any of these work real good.

Just Chuck Ripple's R390 Page.

http://www.r390a.com/html/history.htm 

As Les keeps it going.

Chuck did a how to hook any wire to the input of an R390. Its been working 
for fellows for a long time.

No need to hack the antenna input on any receiver.

Roger KC6TRU