Topband
[Top] [All Lists]

Re: Topband: Vac relay keying

To: "MR TREVOR DUNNE" <ei2glb@eircom.net>, "'topband List'" <topband@contesting.com>, "Richard \(Rick\) Karlquist" <richard@karlquist.com>
Subject: Re: Topband: Vac relay keying
From: David Cutter via Topband <topband@contesting.com>
Reply-to: David Cutter <d.cutter@ntlworld.com>
Date: Wed, 15 Nov 2017 10:10:04 -0000
List-post: <mailto:topband@contesting.com>
Trevor

That circuit works well if you only have a 13V typical radio supply. You can string several relays from the T/R line but remember to fit a 1N4000 type diode across the relay, + end to supply, -end to the T/R line.

It's important to take into account your linear amplifier (if you are using one) as well. If you have a radio that can delay RF after sending the PTT/transmit signal, that is an advantage to avoid hot-switching.

The slowest relay in your system might be the one in the amplifier, but that's slow to energise and slow to de-energise. Make yourself a little timing diagram of what you need. I think this is in various handbooks.

Give more info on your *complete* set up.

David
G3UNA



----- Original Message ----- From: "Richard (Rick) Karlquist" <richard@karlquist.com> To: "MR TREVOR DUNNE" <ei2glb@eircom.net>; "'topband List'" <topband@contesting.com>
Sent: Tuesday, November 14, 2017 9:37 PM
Subject: Re: Topband: Vac relay keying


See:

www.k6xx.com/radio/fastrely.pdf

Rick N6RK

On 11/14/2017 11:51 AM, MR TREVOR DUNNE wrote:
Hi Guys

Can someone point me in the direction of a circuit I can use to key a 26v vacuum relay using the tx out on my rig,

I have a 24v PSU I just need to know how to switch on the feed to the relay as quick as possible when I TX,

Thanks
Trevor
EI2GLB
_________________
Topband Reflector Archives - http://www.contesting.com/_topband


_________________
Topband Reflector Archives - http://www.contesting.com/_topband

_________________
Topband Reflector Archives - http://www.contesting.com/_topband

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