[Elecraft] Keying an amp

[Guy Olinger, K2AV]

Phil, don't hook this up directly any more.

By my information the 30L1 has a minus (-)170 VDC key line.  You are
actually keying 811A final tube grid cutoff bias, not a relay in the 30L1.
This line was meant to be hooked up to a relay in one of the Collins S-line
units.

The K3 only handles POSITIVE keying voltages.  You will have to use an
intermediate relay to key the 30L1.  Many have modified the Collins to
provide a more standard positive 12V through the coil of a reed relay which
in turn grounds the -170  volt grid cutoff bias from the 30L1.

This is a different problem than the +120V from the old SB220 amps, which
the K3 *can* key.

73, Guy.

----- Original Message ----- 
From: "Phil LaMarche" <plamarc1 at verizon.net>
To: "'Christopher Kovacs'" <w0anm at charter.net>
Cc: <elecraft at mailman.qth.net>
Sent: Sunday, February 08, 2009 2:05 PM
Subject: Re: [Elecraft] Keying an amp


>
> When I take the cable from the K3 directly to the 30L-1 it keys the amp
> w/o
> being manually keyed.  It's in Key Out.
>
>
> Philip LaMarche
> LaMarche Enterprises, Inc.
> www.instantgourmetspices.com
>
> www.w9dvm.com
> 800-395-7795 pin 02
> 727-944-3226
> FAX 727-937-8834
> NASFT 30210
>
> K3  #1605
> W9DVM
>
>
>
> -----Original Message-----
> From: Christopher Kovacs [mailto:w0anm at charter.net]
> Sent: Sunday, February 08, 2009 12:51 PM
> To: Phil LaMarche
> Subject: Re: [Elecraft] Keying an amp
>
> What kind of amplifier are you using?  You have to be careful about the
> keying voltage and polarity.
>
> Chris
>
> Phil LaMarche wrote:
>> Hooking up an amplifier through an amp key to key out.  Is there any
>> menu that needs to be changed.  Don't see it in the book but when I
>> plug in the amp it keys.  Take out the keying device and direct, it
>> still keys.  Looking in book to no avail.
>>
>> Phil
>>
>
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