Keywords: Vactrol AGC (Yushin).PNG Basic +20dB automatic gain control cell - as used in 1970s telephone networks Adapted from A V Yushin 1998 in Russian Оптоэлект онные п ибо ы и их за убежные аналоги Optoelectronnye pribory i ih zarubezhnye analogi Radiosoft Moscow Volume 1 ISBN 5855540000 p 323 <br> Note that capacitor values are chosen to narrow passband to telephony standard; hi-fi passband would need at least 100nF values for both C1 C2 own 2010-11 East of Borschov <span class signature-talk >talk</span> 08 57 16 November 2010 UTC Drawn in Proteus v 4 underlying schematic is PD Vactrol |