scooterspal wrote:
...I'm simply patching the output of my portable
mixer into the existing mic jack on the unit. I'm doing away
with the 48" extended mic cable and the antenna that is part of it.

Holding out 4' of wire will not work for my needs. I need to use
a fixed antenna.

Will any antenna designed for 75-76mhz work?

Aside from the differences in level/impedance between
your mixer and the original mic, the simplest hurdle
is the floating shield on the orig mic that they
use as the antenna.

I don't recall now the freq of your device. But antenna
length probably won't make a huge difference. A 48 inch wire
might give you just the same performance as a 12 inch wire.

If you're going into the guts of the transmitter to
connect the mixer, that will reduce the antenna float
problem. But if you're somehow plugging the mixer output
into the mic input, then the shield/ground of the mixer,
perhaps all the way back to the 3rd lug ground in the AC
wall supply (if it's AC powered), will become the antenna.

There might also be some kind of DC power on the mic
line from the transmitter to power a condensor mic.

There's just a ton of variables. And it all seems to
hinge around them using the mic cable for the antenna.

PERHAPS a simple solution would be to use an impedance
matching xformer (Shure, RatShack etc) between the mixer
output and the transmitter input. Make your mixer to
transmitter cable 48 inches long, use the xformer between
the mixer and that cable, and use the cable as the antenna,
as originally designed. In other words, replace the mic with
a transformer and appropriate connector to mate with your mixer.
The transformer would tend to isolate the mixer from the antenna
somewhat, as well as matching the two audio levels a little better.

[Transmitter]---mic cable 48"---{|xformer|]--[Mixer]


Lumpy

Did you do a lot of those Emergency Broadcast Warnings?
Yes. Had it been an actual emergency I would have hid.

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