Carter, Facts: 1) The Kenwood mic wiring is very similar to the Elecraft - all mic header pins wired straight across except pins 5 and 6 which may be not connected or pin 5 may be connected to 5 volts. See the KSB2 manual for details. Since your Kenwood mic is a dynamic type you should have no resistor wired to the back of the mic jack.
2) The ProSet-K2 needs to have a 5.6k resistor from +5v to the AF line (pin 1) to power the electret element. You can check the mic jack pin 5 to see whether it has 5 volts on it or not - you can do that without opening the K2. If you do find 5 volts present on pin 5 it would be possible to put a 5.6k resistor inside the Proset-K2 adapter between pins 5 and 1 - it would be a tight fit (use a 1/8 watt size for an easier fit), but that would be the only thing needed. If you do not have 5 volts on mic pin 5 or you do not like the idea of mounting the resistor inside the adapter/plug, there is another solution, but it involves getting into the K2 (that should not break it in any way) and wire the mic configuration header to the Elecraft 'standard', then alter the Kenwood mic. The alteration needed on the Kenwood mic is to be certain nothing is connected to pins 5 and 6 at the plug end of the cord, and somewhere in the AF (pin 1) line, you need to place a capacitor about 1 uF in value. The capacitor would likely fit most easily into the head of the mic, there just is not adequate room in the plug. If you use an electrolytic or other polarized type, the + side should go toward pin 1. As yet another solution, you could build an alternate external adapter for either mic. Details of the connections would depend on your choices of how you wish to have the K2 mic jack pinout. I would suggest that the external box would be a better solution IMHO, and I would include switching from one mic to the other inside that box too, but then that is just my way of tackling the situation, your choices may differ. I would even include adding fixed audio output to the mic jack and add a computer soundcard interface inside the switching box too, in fact my mic switching box does exactly that and has provisions for 3 mics, one of which needs a preamp (also inside the box), and I can plug an Elecraft wired mic directly into the K2 for forays with the K2 portable. 73, Don W3FPR > -----Original Message----- > > Before I go and lay out $147.00 for a Heil ProSet-K2 headset to go with my > ancient K2 (S/N 678, Revision B, with software version 2.03d), can you > helpful folks tell me about any pitfalls to installing this unit? > > Will I have to open up the rig and make any modifications? My K2 > is working > so well that I really don't want risk breaking something that > isn't already > broken! > > Right now I am using a simple Kenwood 600-Ohm dynamic hand microphone, and > that mike works very well, but I thought I'd like to try using a headset, > since my hearing needs all the help it can get. So my K2 is presently > configured to use that Kenwood mike. > > Should I stay clear of this headset? I tried using ANOTHER Heil > headset (not > one configured expressly for the K2) a few years ago, and had problems > getting the VOX to trip properly, as I remember, and I think my received > signal reports were not so good... > > Any ideas? > > 73, > > Carter > _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
