Topband: TX relays

[GeorgeWallner]

On Fri, 10 Oct 2014 11:13:14 -0700
  Paul Baldock <pbaldock at frontier.com> wrote:
> One solution to the receiving problem when using high 
>current relays may be to have dc current (eg 100mA) pass 
>through the contact in RX. 

1. In all my antenna systems I always use some wetting 
current. I feed from 24 V about 2 mA of DC wetting current 
via a 1 mH choke and a 4k7 resistor at each end. I used to 
have receive problems with all kinds of relays, including 
vacuum relays, before I added the wetting current. Since 
then, all relays have been working perfectly in RX (via 
the normally closed contacts).

2. For TX above 500 W I use vacuum relays. Where the SWR 
is low I use RJ1A (HC-1) or RF1D ((K45C) or similar types 
and where the SWR could be high I use RJ4 (KC-2, KC8 or 
H-8) types. Overkill? Maybe. But...

73,

George
AA7JV