[Elecraft] DSL filters as RFI filters -- don't bother!

[Stephen W. Kercel]

I have found KCOM filters very effective at cutting out telehone RFI. 
I have found that the KCOM handset filters do interfere with the 
proper operation of some cheap telephones. I have not run into any 
problems with the KCOM line filters.

73,

Steve
AA4AK
K2 S/N 5383


At 02:34 PM 4/17/2006, Vic K2VCO wrote:
>I've collected a large number of DSL telephone filters from various 
>installations.  Someone recently suggested that they can be used as 
>ham RFI filters, since they are supposed to isolate the telephone 
>from the DSL carrier.  Although the DSL signal is much lower in 
>frequency than ham signals (I believe 10-100 KHz, correct me if I'm 
>wrong), I thought it would be worth a try.
>
>I tried four different types of DSL filter and compared them to a 
>KCOM RFI filter designed for 3-30 MHz.  I transmitted 100w CW on 7 
>MHz into a vertical.  With no filters, the keying could clearly be 
>heard.  The KCOM filter was quite effective, suppressing most of the 
>interference.  The DSL filters appeared to have no effect.
>
>So much for that idea.
>--
>73,
>Vic, K2VCO
>Fresno CA
>http://www.qsl.net/k2vco
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