[RFI] Sitting position and RFI ...

[Michael Carter]

David,

You didn't conclusively identify the signal source that was opening
the squelch.  However, your body may be the necessary
attenuator to prevent the squelch opening in just
the right body posture.  A slight shift in posture is
enough to increase the squelch-breaking signal
strength at the HT.

For what it's worth, I use my body as an absorber
when DF'ing RFI sources with a 135 MHz handheld
receiver and a simple helical whip.  The body absorption
is sufficient to remove the whip's null direction ambiguity
when held horizontal and swung in the azimuth direction.

73,
Mike, K8CN
________________________________
From: RFI <rfi-bounces+mike.carter=unh.edu at contesting.com> on behalf of QRV at kd4e.com <QRV at kd4e.com>
Sent: Monday, January 31, 2022 3:55 PM
To: RFI at contesting.com <RFI at contesting.com>
Subject: [RFI] Sitting position and RFI ...

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Riddle me this ...

I'm sitting at my desk and my handheld is sitting on a wood shelf

just behind the HP laptop.

The HT is on and set to monitor 146.670 (it has long thin flex antenna).

All of a sudden the squelch opened to static.

I walked around with it and it seemed that the source might be the

inline UHF amplifier that feeds two rtl-sdr devices, or the cellphone

repeater. Note: Both devices are located on the other side of a 4x8'

steel door from the handheld, laptop, and me.

When I sat back down at my desk it was quiet, then when I moved,

it started, again.

Yup, it's responding to the position of my body relative to the laptop

and mouse.

Sitting back, away from the desk opens the squelch, leaning forward

quiets it.

WDYT?

David KD4E

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