I have had good experience with the cheap "Princess Type" phones from Radio
Shack. Unfortunately the XYL likes to use the 900mhz phones and the phone in
the kitchen ( a SONY with Answering machine). These other phones are very
bad in RF fields. However I have modified them all using AG6K
double-filters, bypassed and placed Ferrites on the power cords. The cost of
components for the AG6K filters was about $50 .. enough to do about 25
telephones! I used Tantalum 22uf as well as .1uf and .01uf caps on the
incoming power. Type 43 Ferrite was used getting as many turns of the power
cord around it as the length of the cord would permit. All but the SONY
are completely free of interference. The SONY ( per my XYL ) has an
'acceptable' amout of interference. She can hear me on 10 meters, but can
ignore it because of the attenuated audio. Check the AG6K web page for
details on the filters ( and DigiKey part numbers ).
Bill Turner, W7TI wrote:
> On Tue, 8 Dec 1998 06:47:52 -0500, "brad roope" <w1rqbrad@mdc.net>
> wrote:
>
> >
> >Re: Radio Shack Telephones.
> >
> >Remember some comments on Radio shack Phones. Does anyone have model
> >numbers on what phones may reduce or eliminate RFI? Also are the K-Comm
> >filters any good?
> >
> >Thanks brad W1RQ
> ______________________________________________________________
> It might have been me you remember. I have a Radio Shack phone that
> is totally free of RFI without any filters at all, even running 1500
> watts SSB and the antenna being only about 60 feet from the phone.
> Unfortunately there is no model number on the phone, but it's the one
> with the transparent case so you can see all the circuitry inside.
> It's in what used to be known as the "Princess" style, meaning the
> handset had the pushbuttons in it and rested in a separate cradle when
> not in use. Hope this helps.
>
> 73, Bill W7TI
>
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