KX3 Relay Control For Desktop Amplifiers

[Robert W Schumacher]

Most common desktop amps have a relay circuit that requires a transceiver to short 12 VDC at 100 ma to key the amplifier on.
In the KX3 specs, the maximum amp relay current is stated to be 100 ma. Has anyone keyed a desktop amp directly with a KX3 or is it recommended to use an intermediate external relay circuit?

Thanks,

W9DBR
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[Mike Furrey]

You might try installing a "soft key" kit in the amp if the voltage and
current requirements may be a bit high for the KX3.

73, Mike WA5POK

--------------------------------------------------
From: "Bob Schumacher" <[hidden email]>
Sent: Tuesday, March 12, 2013 12:06 PM
To: <[hidden email]>
Subject: [Elecraft] KX3 Relay Control For Desktop Amplifiers

> Most common desktop amps have a relay circuit that requires a transceiver
> to short 12 VDC at 100 ma to key the amplifier on.
> In the KX3 specs, the maximum amp relay current is stated to be 100 ma.
> Has anyone keyed a desktop amp directly with a KX3 or is it recommended to
> use an intermediate external relay circuit?
>
> Thanks,
>
> W9DBR
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html 

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[ke9uw]

The continuous rating for the output fet  2N7002 is 115ma. So seems ok at 100ma.

Sent from my iPad
Chuck, KE9UW
(Jack for BMW motorcycles)

On Mar 12, 2013, at 11:07 AM, "Bob Schumacher" <[hidden email]> wrote:

> Most common desktop amps have a relay circuit that requires a transceiver to short 12 VDC at 100 ma to key the amplifier on.
> In the KX3 specs, the maximum amp relay current is stated to be 100 ma. Has anyone keyed a desktop amp directly with a KX3 or is it recommended to use an intermediate external relay circuit?
>
> Thanks,
>
> W9DBR
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html