Martin, According to the SM-8 microphone schematic, the UP button connects the UP/DN line directly to ground, but the DN button connects the UP/DN button to ground through a 470 ohm resistor. You would have to convert these closures to 2 lines each of which is a circuit direct to ground, so you would have to provide some sort of level sensing at the input of whatever adapter circuit you would come up with.
Much microphone information can be found on G4WPW's wonderful collection of microphone connections/diagrams/etc. Look at http://www.timroberts-vk4yeh.id.au/G4WPW_mic_connections/index.htm#icom 73, Don W3FPR DM4iM wrote: > List, > According to the Icom SM-8 Desktop Microphone manual, there is only 1 > wire for the Up and Down buttons. > So i suspect Icom feeds a positive voltage for up and a negative voltage > for down (or vice versa). > How to adapt this to make it work with K3? > I had good audio reports so far. > > Martin > > > ------------------------------------------------------------------------ > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 9.0.725 / Virus Database: 270.14.129/2605 - Release Date: 01/07/10 > 02:35:00 > > ______________________________________________________________ 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
