MFJ-434 Voice Keyer and Icom radio question
 

Hello,

I have been thinking about purchasing the MFJ-434 voice keyer to use for
contests, Field Day, and I had a few questions for anyone who may own one.
I downloaded the manual off of MFJ's web page and it mentioned that you need
to set the internal jumpers for the proper voltage for your tranceiver's
microphone if you are using any transceiver other than a Yaesu. I recently
purchased a used Icom 720A that is currently being repaired by MTS in
Washington state. The radio didn't come with the HM-7 hand mic, so I am
probably going to have Scott Malcolm at MTS just put together another mic on
the radio for me that has a pre-amp built into it that will work with the
720A. I was wondering if anyone knows what the proper voltage is for this
microphone? The 434 listed voltage jumpers of something like 0, 2.5, and 5
Volts, but I'm not sure what the proper voltage for my mic would be, or even
how to find out exactly. I have a VOM that I can use if I knew what I need
to do to determine the mic voltage from the transceiver. Has anyone used
the 424 with an Icom rig, or even with 720A, and can you tell me what I need
to set the voltage jumper for? Is the 434 a good keyer, given MFJ's
reputation, and where is the best place to buy one? I live about a two hour
drive from Ten-Tec, so I was thinking about buying one from them in case I
had a problem with it and had to return it. Can anyone help me with this
one? Thanks for the help!

73,

Michael Brown KU4UV
Lexington, KY.