John, You can use the amp keying circuit described for the K2 on the Elecraft website http://www.elecraft.com/Apps/Amp_keying_ckt.htm. With the K1, you would use the 6R signal line in the K1 to drive it.
If your amp relay voltage is higher (or the current required is higher) than can be handled by a 2N2222, take a look at the circuit used by Tom Hammond at http://www.n0ss.net/k2_t-r_rly_drvr.pdf. Unfortunately, Tom cannot supply kits at this time, but it is not difficult to construct this circuit on perfboard. 73, Don W3FPR On 7/26/2011 10:20 PM, VK7JB wrote: > Hi All, > > I have a K1 and also a cute, but rugged, little Tokyo HP-45b amp, which puts > out about 45W and I take it camping. I've been thinking of pairing the two. > The THP amp doesn't have RF sensing for switching. Can anyone point me in > the direction of a simple way to key the amp with a K1 / KX1? Are there amp > keying buffer circuits you can make up and use with the K1/KX1? > > Perhaps someone out there has done this successfully already. I can't find > much in the archives, so perhaps others have worked out that it's not worth > the fuss?! :) > > Thanks! > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html

