[Amps] Relays

[Paul Christensen]

> The RJ-1 type of relay can also be completely silent if you mount it
> with a few drops of silicone seal or on a piece of soft rubber. Mount it
> directly to metal if you like to hear it click!

Good suggestion, Vic.  Although typically, that's half the solution. 
Generally, cabling going to the relay's pins contributes much to sound 
conductivity.  For example, RG-213/214, RG-142 and coaxial cable of other 
sizes are often found terminating directly onto the relay's pins.  With 
RG-213/214, the wiring size can become the limiting factor in the 
transmission of the relay's sound -- even if the relay is shock-mounted.

I cut small 1"-2" loops made from ultra-flexible silicone HV wiring and use 
it to bridge the end of the coax to the relay pin.  The loop creates a 
cushioning effect.  Not much of a length, just enough to let the relay's 
vibration dampen and dissipate in the wire.  Same with the coil pins, if 
necessary.  Between shock-mounting the relay and using the flexible HV 
wiring, all that is left is a slight tick -- but still not as quiet as a PIN 
diode <g>.

Paul, W9AC