[TenTec] Ten-Tec amplifier vacuum relay noise

[Ken Brown]

I have a Titan 425 and a Hercules II 420 amplifier. The vacuum relays in 
the two amplifiers appear to be the same model. The vacuum relay in the 
425 makes much more noise. I know it uses a higher voltage to actuate it 
that the 420 does, 20 V versus 13 V. That may be part of the difference 
in noise. I am wondering if differences in the mounting of the relays 
and the stiffness of the wires connected to the relay is also an 
important factor in the amount of noise radiated (acoustically) from the 
relay. I am considering replacing the grommets that the relay board is 
mounted with, and adding short lengths or braid in the connections to 
the relay (not stiffened by being totally soaked full of solder) to help 
isolate the relay vibration from the rest of the chassis.

Anyone out there tried any of this already? I'd be interested to hear 
about your successes and/or failures.

DE N6KB