Towertalk
[Top] [All Lists]

Re: [TowerTalk] Help need Vacuum Relay Isolation 1.8 to 30 MHz

To: "RCARIELLO" <RCARIELLO@si.rr.com>,"Jim Lux" <jimlux@earthlink.net>,"Towertalk" <Towertalk@contesting.com>
Subject: Re: [TowerTalk] Help need Vacuum Relay Isolation 1.8 to 30 MHz
From: "Tom Rauch" <w8ji@contesting.com>
Reply-to: Tom Rauch <w8ji@contesting.com>
Date: Wed, 5 Jan 2005 14:40:30 -0500
List-post: <mailto:towertalk@contesting.com>
Hi Rich,

If the wiring is what it sounds like to me, you are really
setting yourself up to eventually seriously damage your
radios.

> Two relays mounted next to each other in an aluminum box.
No shielding
> between the relays. Both normally open. Connect one
terminal from each relay
> together and to an SO-239 connector feeding outside the
box to a 50 ohm
> dummy load.

What happens if one relay sticks and does move, has an open
coil and doesn't move, or a wire breaks? What happens if you
get a short someplace? What happens if a contact welds?

Look carefully at your contact wiring. If there is ever a
possibility a relay or electrical failure can cause two
radios to connect to one antenna port, I'd strongly suggest
you buy different relays!!

If you intend to build a crossover switch, you should at the
very minimum use a DPDT relay that has a reliable armature
that is always synchronized.

73 Tom

_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>