Jim, I can see that magnetic fields in a vehicle could cause problems with a microphone, as the output level is in the -50dBm range and is much more susceptible to it . Using equipment like the KX3 at consumer line level (-20dBm) there would much less of a problem with magnetic fields, so a less expensive, unshielded in-line transformer would probably work just fine.
73, Rich - K1HTV = = = -----Original Message----- From: Jim Brown [mailto:[email protected]] Sent: Wednesday, June 01, 2011 13:04 PM To: Reflector Elecraft Subject: Re: [Elecraft] KX3 Audio output On 6/1/2011 5:31 AM, Rich - K1HTV wrote: > Looks like the addition of an inline audio transformer between the > wireless transmitter's miniplug and the KX3 (or any device powered by > the vehicle) would resolve the potential problem which you have addressed. Yes -- IF the transformer did not pick up magnetic fields from the vehicle's systems. I saw that when doing testing of some pro mics for RFI in a Volvo S80 -- the output transformer in the mic was not shielded, and picked up trash. That would be fixed with a transformer that has a mu-metal shield, but shielded transformers are expensive. 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
