摘要 |
PCT No. PCT/SE85/00471 Sec. 371 Date Jun. 20, 1986 Sec. 102(e) Date Jun. 20, 1986 PCT Filed Nov. 19, 1985 PCT Pub. No. WO86/03354 PCT Pub. Date Jun. 5, 1986.A circuit for eliminating signal hum includes, in series, an adder 17, a delay circuit 13, an amplifier 19 and a subtractor 14. Connected in parallel with the delay circuit is a feedback loop having an amplifier 18 connected to one input 172 of the adder. The circuit input 11 is connected to the input of the series coupling, and to an input 142 on the subtractor. The delay circuit has a control input connected to a second signal input, via a synchronizing circuit 16. |