[UK-CONTEST] re ADSL Modem RFI

[Chris Tran GM3WOJ]

Hello Steve, Ian, David, Alex

Thanks for the extra input and suggestions. I've removed some house 
extension wiring, improved the shack earth system and ditched my 'Safecom' 
router (which seemed OK in the past) and now using a BT HomeHub2 which seems 
better for RFI - I think it is a Thompson router inside but not sure. The 
RFI from 160m and 80m is much less.

As I understand it, the 'ADSL Microfilter' which is needed on all phone 
points is a High-pass filter - to separate out the ADSL from the audio 
signal - the ADSL download bandwidth is up to about 1.1MHz (ADSL2 = 2.0MHz?) 
so I had the cunning plan to change a Microfilter into a bandpass filter, 
with an upper cut-off frequency of about 1.1MHz as per the commercial 
filters mentioned. However I gave up on this idea cos (a) it should be in 
screened metal box and (b) the microfilter is usually some distance from the 
router ADSL input and (c) I couldn't figure out the existing microfilter 
circuit.

I've also tried unsuccessfully to monitor the ADSL S/N ratio so that I could 
see degradation or otherwise - tried Router Stats, Router Stats Lite and DMT 
software but they all seem very router-specific - does anyone know the URL 
for the BT HomeHub2 stats page ?

73
Chris   GM3WOJ
GM7V in CQ WW CW 2009+