Hi Todd,
Tnx for your note. I've removed the ARB704 interface and all is well. I've fingers crossed that the pulse canceling diode remains healthy. When I posted my question, I'd had trouble finding the specs on the K3 keying circuit in the manual - they're there, but couldn't find them!. I felt happy when I found it's so robust. Thanks for your interest. 73 John VK7JB On 08/09/2012, at 1:48, "Todd - k1tm [via Elecraft]" <ml-node+s365791n7562241...@n2.nabble.com> wrote: > The AL-811 manual states that "Relay: keys amplifier when grounded. Sources > +12 VDC open > circuit and supplies 100mA when grounded. A built-in pulse canceling diode > protects the exciter. " > > The K3 is pretty robust "KEY OUT (RCA/Phono) is the amplifier T-R relay > keying output, capable of keying up to +200VDC @ 5A." The relay coils back > emf is contained by the diode across it. > > So, no issues switching the AL-811. 5A's and 200Vdc withstand voltage, beats > 100ma and an applied 12Vdc source all day long. > > 73 > > If you reply to this email, your message will be added to the discussion > below: > http://elecraft.365791.n2.nabble.com/K3-and-AL-811-amplifier-interfacing-tp7561650p7562241.html > To unsubscribe from K3 and AL-811 amplifier interfacing..., click here. > NAML -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-and-AL-811-amplifier-interfacing-tp7561650p7562260.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
