On 12/15/2010 8:23 AM, rick darwicki wrote:
> I have large multiturn LF and HF material chokes on my old portable phone
> line, right at the phone.
What's a portable phone line? Do you mean a radio-based wireless
extension of your wired phone line? If this is what you're describing,
I'd guess that your body is acting as an antenna to couple 10M RF into
the portable handset (which is really a UHF radio transceiver), and the
poorly designed circuits in that portable handset are detecting the RF.
When you grab the ferrite choke with one hand, the RF current carried by
your body is being diverted away from the portable handset to the
The above is a WAG. :) But think about it -- when you use a 2M talkie,
your body is acting as the return for antenna current through the rubber
duck, just like radials are acting like the return for antenna current
with an HF vertical antenna, or the car body acts as a return for
antenna current with a mobile antenna.
73, Jim K9YC
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