FW: [RFI] Telephone Interference -

Peter D. Vouvounas Peter D. Vouvounas" <wb3fsr@home.com
Sun, 2 Jan 2000 17:34:10 -0500

-----Original Message-----
From: Peter D. Vouvounas [mailto:wb3fsr@home.com]
Sent: Sunday, January 02, 2000 17:29
To: Dana Roode
Subject: RE: [RFI] Telephone Interference - blowing out phones?


Thanks for your insight into T-RFI.....

When we purchased our home about a year ago near the Ocean (Jersey Shore
Area) I found that I had all kinds of RFI in our house, Telephone RFI - TVI
on the cable etc.

I am most interested in the "GE" phone issues that you have worked on, any
more info would be great as we have a "GE" Kitchen wall phone (single line)
and I have a "GE" two-line desk phone in the basement (my office)...  Both
are the worst for T-RFI that I have ever seen also have problems with them
on 2 meters/440 and FRS.

I contacted the US Distributor for the "GE" phones and they said that they
would send RFI filters for both phones out to me.  That was about a month
ago & haven't seen them yet.

So please keep me in the loop on your experiences and successes in resolving
GE phone RFI problems

Regards, 73



-----Original Message-----
From: owner-rfi@contesting.com [mailto:owner-rfi@contesting.com]On
Behalf Of Dana Roode
Sent: Sunday, January 02, 2000 17:20
To: rfi@contesting.com
Subject: [RFI] Telephone Interference - blowing out phones?

RFI Folks,

Let me update you about the problem I reported below.  First off, I
would like to thank all of you who responded to my e-mail, I've not
had a chance to reply to each of you.  I received about 20 replies
with all sorts of useful information, suggestions, and moral support.
This list is a great resource.  I will not need to resort to QRP.

I responded to my neighbor's angry letter in a very diplomatic
fashion, ignoring the threats, and concentrating on the issue at
hand.  I explained the situation to her, noting that it was a
"technical problem, not a legal problem" (quote from one of the RFI
write-ups), and pointed her to the URL for the FCC phone RFI bulletin:


This is a great document that spells out the situation for the
consumer.  Its particularly important since it comes from the FCC and
not me or some Ham organization.  I closed my letter to my neighbor
with an offer to help, if she was willing to work with me (without the

My neighbor responded in a positive fashion, I asked her some
questions, and setup a time to help debug the situation.  The phones
involved were the wired variety, she had given up on cordless earlier
because of interference from me.  The fix I gave her for TVI last
March was working fine.  The telephone interference wasn't literally
constant, it was a weekend/evening thing, fitting my operating

I did my homework, read the ARRL RFI Book chapter on phone RFI (the
ARRL's book is *very* helpful), read other write-ups on the Web, and
all of your e-mail.  I ordered a "bullet-proof" phone from
Pro-distributors in Texas - I planned to leave it with my neighbor if
necessary and use it as a "debug" device otherwise.  I also got a $20
RadioShack 43-591 phone, which you folks thought was good in RFI
situations.  I got plenty of FT140-43 toroids from Amidon (they are a
few miles away), and a couple of K-Com phone filters.

I arranged a time for my brother, KA6CCF, to key the rig while I was
at my neighbor's house.  Wow, her GE wall-phone heard me on every
band, even without the Amp.  In fact, her phone picked up the small
FRS walkie-talkie I was coordinating with my brother on too.  These
phones are great receivers.  I tried the RFI phone - problem was gone,
indicating there was no audio rectification elsewhere on the line.  I
tried her phone connected through a cord over 9 turns on a FT140-43 -
problem solved.  I didn't even need a K-COM filter.

When my brother transmitted on 10 meters, I could hear a thunderous
sound echoing throughout my neighbor's house.  No wonder she was
angered after my 10 meter contest weekend.  Her son's stero was the
culprit, eventhough it was turned off.  A FT140-43 on the stereo side
of each speaker lead solved the problem.

I told her to log further problems - date, time, severity - so I could
figure out frequency, reproduce and resolve them.  In the end, my
neighbor was very appreciative, and didn't attribute the problem to
me.  I think the FCC document was key in putting things in perspective
for both of us.

Thanks to everyone for your help and advice.  Now, on to solve my
power line noise problem, which has made the radio fairly useless over
the past few weeks.


PS: Can 400w from an antenna 30 feet away blow out a phone?  Most
folks, including me, thought not.  Ed Hare did a quick computer model
of the situation, and from his information I came away thinking it was
possible after all.  And, my neighbor had no reason to make it up (she
never asked me to pay for any broken phones).

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