[Elecraft] k2 with ameritron 811

[Dale Boresz]

Donald Nesbitt wrote:

>Hi Dale - I don't have the same amp as you - and - don't know if the keying
>circuit you are using for the K2 is the same as I am using (built mine from
>the same article I think) - but - I found that both my 30L-1 and my FL-2100B
>had NEGATIVE keying lines and the little "kit" could only key POSITIVE
>lines.  When connected to a negative line it kept the relay keyed all the
>time (that would explain your xmit lamp being lit all the time - ie: the
>relay is already trip'd.)  I had to add a small reed relay to mine in order
>to key the NEGATIVE keying lines from the linears.  You could check the
>keying line from the AL-811 with a VOM to see if it is positive or negative.
>Have fun  --don  K2/100 #2028
>
>BTW - the keying circuit for external amps that is built in to the KPA-100
>is also set up to only key POSITIVE lines - what a pain!!
>
>----- Original Message -----
>From: "Dale Boresz" <dmb@lightstream.net>
>To: <elecraft@mailman.qth.net>
>Sent: Sunday, April 27, 2003 11:29 PM
>Subject: Re: [Elecraft] k2 with ameritron 811
>
>  
>
Hi Don,

Well, this isn't as nice as our previous K2/K2 QSO's on 20m SSB, but it 
has it's uses!

Anyway, my amplifier and John's are the same - an Ameritron 811H, which 
has a positive voltage which must be pulled to ground to drive the 
relay. The circuit worked fine for me, so I suspect the problem is just 
a bad connection somewhere that's either not driving the switching 
transistor hard enough, or the ground to which the relay line is being 
pulled, has a questionable connection.

Look forward to chatting with you again on 20m, now that the band is 
coming back! Still spend most of my time on CW, but I occasionally get 
on 20 meter phone for a little while on the weekends.

73,
Dale - WA8SRA