Topband: RF Relays

[MorgusMagnificen@aol.com]

I have taken apart many commercial relays looking for good ones for RF 
switching. I use them extensively in auto-tune amplifiers which I have been 
building. Most (all?) of the relays I have studies had one or more problems, a 
frequent one being poor insulation and/or isolation between contact structure members 
and the armature. But a while back I happened to find an outstanding relay 
and bought up all of them for resale to ham friends.

It is a power-rated SPST relay in a fairly small (not miniature) sealed 
plastic enclosure with PC contacts. It is power-rated at 30A and the contact 
spacing is about .050, which is plenty for low-Z switching. The contacts are plated 
and have good wiping action and most importantly, there is excellent isolation 
between contacts and actuator. Anything in physical contact with the contacts 
is PVC plastic. It is built similarly to a contactor and also has very low 
inductance in the RF path. The coil is 24DC at 20ma. 

Since it is already sealed, using these in a sealed "main" enclosure should 
weather well. I am charging $2 ea. plus shipping from 48442. Most switching 
systems can be built using 5-10 of these. 

73,
Eric von Valtier K8LV