[Elecraft] Key Out Jack

[James Wilson]

Pete, I think you have misunderstood the purpose of the Key Out jack
on the K3.  It does not provide 12 volts out at 40 ma. It is a keying
circuit that can withstand a external keying circuit up to +200 volts
DC and can handle a keying load of up to 5 amps. (See the K3 manual
regarding the Rear Panel) If you want to key your external relay, you
will need to provide a source of power for the relay - and use the Key
Out connection as the "switch" for it.

Jim - W4RKS

--------------------------

>I am trying to use the Key Out jack on my K3 to key a small relay to
>protect my SDR from RF.  The 12V at 40 <http://mailman.qth.net/mailman/listinfo/elecraft> ma is well within the stated rating
>of the jack, but to my surprise it does not work.  Measuring with an
>analog multimeter, the jack appears to be shorted all the time, and also
>to have a very small DC voltage on it.  I don't have a schematic for the
>radio, so I'm stumped.  Is this a function of the way I'm measuring, or...?

-- 

>73, Pete N4ZR