On Sun,8/16/2015 7:17 PM, Brian Denley wrote:
Don't electrets have to be powered (voltage applied) where dynamics do not?
Right. On Sun,8/16/2015 8:00 PM, James Wilson wrote:
Yes, the electret mics do require a small amount of power - Elecraft and others call it BIAS voltage.
It's called bias because it IS bias -- electret capsules have a very high output Z, so they use a FET follower as an output stage. The voltage provides bias for that output stage.
Fortunately - with the K3 and K3S and very likely the KX3 also - that needed bias is available and can be turned on or off with a menu selection.
Virtually all modern rigs (within the last 30+ years) provide V+, usually about 8 V, on one pin of the mic connector. All it takes to use that for bias is a resistor in the range of 5K ohms from V+ to the mic input.
73, Jim K9YC ______________________________________________________________ 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 Message delivered to [email protected]
