[Elecraft] External AMP

[Don Wilhelm]

Ray,

That relay power is normally provided by the amplifier - you do not need 
any voltage from the transceiver unless there is some strange and 
unusual circuit involved.

Measure the voltage at the "PTT" or "KEYIN" jack of the amplifier.  Is 
it AC or is it DC?  If AC, it will not work with the K3S which needs for 
the voltage to be both positive and DC.

If it is DC, what is the polarity?  It must be a positive voltage.

Many older tube amplifier designs depended on hard relay contacts for 
keying that cold work with AC or DC and did not care about polarity.
In today's solid state world, one must care about such things.

On 11/30/2018 10:02 AM, Raymond wrote:
> I am using my ancient Heathkit SB 230 (original tube) with my K3s. Is there a way to get 12 volts out of acc connector to power relay?  Using K3 external plug for P3 power.
> Ray
> W8LYJ
> 
> Sent from my iPhone
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