Hi Chris, It is very likely that the cause of interference pick-up (not the actual source) is BT's odd wiring scheme. The extensions use a third wire for the ringing signal. This unbalances the wiring making pick-up more likely on extensions. The ringing signal is basically just the incomming line "B" DC blicked with a 1.8uF capacitor. This is only required for old phones with mechanical ringers. Try disconnecting the ring wire at the master socket. It's connected to terminal 3 and should be Orange with White bands. Leave just terminals 2 and 5 (Blue with White bands and White with bands) connected to the extension sockets. Even if you are not having trouble this will often produce a substantial increase in speed. See http://www.wppltd.demon.co.uk/WPP/Wiring/UK_telephone/uk_telephone.html for info on phone wiring.
Robert G8RPI. ________________________________ From: Chris Wilson <[email protected]> To: 'Discussion of precise time and frequency measurement' <[email protected]> Sent: Thursday, 18 July 2013, 18:28 Subject: Re: [time-nuts] Thunderbolt SMPS question > Hi > It's also likely to have issues if you don't have something between -7 and > -13 on the V- supply. Current is low (10ma?). A good linear regulator is > useful on the +12. The +12 rail drops back to < 200 ma under most conditions > once the oven has warmed up. > Bob 18/07/2013 18:26 Thanks Bob, Robert and Azelio. I spoke too soon, the damned noise is back with the TB and divider supplies unplugged. I was really hopeful I'd cracked it there. Time to call my ISP to get BT out. Living in the sticks satellite internet is appealing right now :) -- Best Regards, Chris Wilson. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
