I have a Speadstream 5260 DSL modem and have had it for about 2.5 years now.
On the higher HF bands, I generally don't have a problem with it. On 80m
when I run high power, it gets knocked out. But that's OK, I don't run much
on 80 except for contests. And it comes back pretty quickly when I stop
transmitting.
At this time, I have no ferrites on any cords. What I am using is high
quality CAT-5 cable on all lines. One thing that may help my situation
though is that my DSL line was put in when they were still running dedicated
lines. I don't share it with my house phone wiring. So it comes up from
the basement where it comes into the house and is a single run of cat-5
grade cable to the room where the modem is (which happens to be the ham
shack).
I guess I've just decided to put up with the interference I have as it isn't
all that bad....
73,
Jon
NA9D
on 1/3/03 12:00 PM, Cortland Richmond at ka5s@earthlink.net wrote:
>
> I worked on RFI and EMC problems associated with DSL, both CAP/RADSL and
> DMT. The telco portion has mandatory immunity testing (under Telcordia
> GR-1089 and telco addenda to that) so is pretty good. But the downstream,
> Customer Provided Equipment (CPE) end, where signals may be only
> microvolts, these have no immunity requirement. Conducted noise at
> residential installations may be in the millivolts -- or even volts -- so
> it's easy to see the problem.
>
> I've seen a specification for *one* vendor's modem that required emissions
> 20 dB below Part 15, a good figure, I think. But immunity, especially to RF
> noise in the power, was a particular problem in one modem I worked with. I
> solved it, though I don't believe they changed the design -- and then we
> changed from CAP/RADSL to DMT in the next iteration.
>
> Cortland
>
>> From: Richard Zalewski <w7zr@citlink.net>
>> Subject: Re: [RFI] Speedstream WiFi network
>>
>> May not be 100% on topic but I have a SpeedStream DSL external modem that
>> has LOTS of problems with HF RF and even low levels. AND the company has
>> not interest in advising or fixing the problem.
>>
>> Dick W7ZR
>
>
>
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