The K3's T-R line output ("KEY OUT") can switch up to 200VDC @ 5A... so it will
easily switch the +120VDC @ 15-30mA from the SB-220.However, it will NOT SWITCH a NEGATIVE T-R line voltage UNDER ANY CIRCUMSTANCES! Users with amps which offer a negative T-R line control voltage will have to provide alternate switching (relay, or solid state). 73, Tom N0SS >phones, mic, >line in, and line out At 10:13 02/12/2009, Lee Buller wrote: >HMMMM.... I thought the transistor on the K3 doing the switching is >pretty tough. I guess we are talking about older amps and not the >ones that use 12 volts to switch. > >I have done the following to.... Radio Shack sells a 5v reed relay >that is pretty darn fast and has good specs. I just used a dropping >resistor from a 12 volt line in series with the reed relay and >worked great for years. I think I used a 180 ohm resistor. Worked >great. Not QSK, but I don't like QSK anyway. Messes with my head. HI > >Lee Buller - K0WA > > > >In our day and age it seems that Common Sense is in short supply. If >you don't have any Common Sense - get some Common Sense and use it. >If you can't find any Common Sense, ask for help from somebody who >has some Common Sense. Is Common Sense divine? >______________________________________________________________ >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 ______________________________________________________________ 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
