[arm-allstar] hum on my allstar nodes

[Doug Crompton]

Hum on local RF nodes is a common problem when transmitting TO your node.
It is usually because you are too close to your node. If the hum stops when
you move to another location, sometimes just a foot or two one way or the
other then that is probably the problem. It happens more often when using
antennas that are mounted on the node itself. One way to get rid of it is
to use those small mag mount antennas that have 10-15 feet of coax and get
it away from your operating position or use an outdoor antenna. Other than
that there is no filtering or other way to eliminate it. If the hum is
constant at any location even walking hundreds of feet away then it is not
this phenomenon.

*73 Doug, WA3DSP*
*http://wa3dsp.org <http://wa3dsp.org>*



On Sun, Apr 26, 2020 at 4:08 AM "Jed Barton via ARM-allstar" <
arm-allstar at hamvoip.org> wrote:

> Hey guys,
>
> So i'm sure i'm not the only 1 with this problem. I've got all my
> allstar pies plugged in.  They each have their own power supply. It's
> the typical wall wart.  They all produce a nice little hum that's just
> annoying.
> I'm sure a lot of you guys have delt with this.  You hear it on the
> node transmitter such as the Shari.  Any ideas for getting rid of it,
> or reducing it?
>
> Cheers,
>
> Jed
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