Hi, Bob,
Have you tried a telephone RFI filter on the connection of this phone to the
phone line? Telephone devices are not usually as good a radiator as are the
great big long-wire antennas they are connected to. One of the Radio Shack
filters may help. You may also need to try a common-mode choke (about 10
turns of the wire onto a Palomar F-140-43 core) on any power supply
connection (usually via a wall cube) to the phone.
>From http://www.arrl.org/tis/tisfind.html :
Palomar Engineers
PO Box 462222
Escondido, CA 92046
USA
Tel: 760-747-3343
Fax: 760-747-3346
Email: palomar@compuserve.com
http://www.palomar-engineers.com/
The static noise sounds like it may be a switch-mode power supply. Does the
phone use one? If so, the common-mode filter may not help much; try one of
the Radio Shack catalog # 15-1111 ac line filters or one of the filters sold
by Industrial Communications Engineers:
Industrial Communications Engineers (ICE)
PO Box 18495
Indianapolis, IN 46218-0495
USA
Tel: 317-545-5412
800-423-2666
Fax: 317-545-9645
http://www.inducomm.net/
Under Part 15 of the FCC's rules, there are NO *specific* limits for
radiated emissions on HF. Part 15 handles HF with conducted limits, but
these generally apply only to the AC lines, not to the phone lines. The
conducted limits are high enough that the level of signals you describe
could be coming from a "legal" Part 15 device. Under Part 15, the OPERATOR
of the device (not the manufacturer) is also responsible for any harmful
interference. Is this a neighbor's device, or one of your own?
73,
Ed Hare, W1RFI
ARRL Laboratory Supervisor
225 Main St
Newington, CT 06111
Tel: 860-594-0318
FAX: 860-594-0259
Internet: w1rfi@arrl.org
ARRL Web: http://www.arrl.org
ARRL Technical Information Service: http://www.arrl.org/tis/
> -----Original Message-----
> From: BOB [mailto:bob@2cls.com]
> Sent: Thursday, August 03, 2000 4:29 PM
> To: RFI
> Subject: [RFI] digital phone RFI
>
>
>
> I am receiving RFI interference FROM a Panasonic KX-TD1232-3 digital
> phone system (reverse from normal RFI). The system is located
> about 150
> feet from the antenna.
>
> I receive a bad noise spike at S-8/9 (on a FT1000MP Mark V)
> every 8 khz
> from 40 mtrs through 10 mtrs (only bands I use), and a S-4/5 continuos
> static noise over the same range.
>
> Panasonic says they don't know of a problem and refuse to do
> anything?
> Any suggestions other than calling the FCC (and maybe hear
> something in
> 2 or 3 years)?
>
> Bob W8GC
>
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