[aprssig] D700 microphone cable

Mike Yetsko myetsko at insydesw.com
Thu Aug 26 23:01:57 EDT 2004

> I don't like having the microphone on the Kenwood D700 attached
> to the base unit.  I am considering using a CAT5 network cable and
> an RJ45 line coupler to mount the microphone up on the dash.  Has
> anyone done this? Were there any problems?
> Is the connector on the microphone for the D700 an RJ45
> connector?  Will ferrite cores be necessary on each end?

Go ahead and try.

>From a theoretical standpoint, initial thinking would be it should stink.
a practical standpoint, there are other considerations.

Mainly, 'twisted pairs' offer better immunity to noise than most coaxial
shielded lines.  But...  'twisted pair' is designed to operate in a
or balanced mode where introduced noise is common mode.

So, it's like asking, of apples and oranges, which is faster.

As I said, there are 'considerations'.  Why does twisted pair seem to
work, at least for some applications.  Well, I'd use 'shielded' Ethernet,
should help.  And while you may not pair up your audio line with a ground,
chances are pretty good that you're pairing it up in the twist with
line that is 'steady state', either high or low, so that at least won't
things.  Unless you have a mic like the Radio Shack HTX-242 that sends
clock and data signals from the mic to the rig.  Even there, the mic cable
will probably be quite, electrically anyway, while you are talking in the

Bottom line is you don't know.  Ethernet wire is cheap, though. Just do it
and try it.


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