TU56 and G888 Module

Hello list! i`am working on the restoration of my TU56 Drive. It has an overvoltage damage. The manual transportlogic control and the transportcontrol by the TD8E is working correct. Now i`am in trouble with the G888 Manchester read/write Modules. Specialy with the adjustment of the zero crossing detector. In the maintanence manual i could not find any information on the correct adjustment and originaly the poti is secured by black paint... Oszi <http://www.familie-rauhut.eu/pic/oszi.gif> The yellow graph is the output of the first Amplifier witch is amplified the read heads outputsignal. The blue signal is the output of the nand driver(7400) after the zero crossing detector. In case of the term zero crossing detector, i placed the rising edge of the output on where the sine wave cross the zero line. Any usefull hints on the adjustment of the "zero crossing" detector? Marco * Englisch - erkannt * Englisch * Deutsch * Englisch * Deutsch <javascript:void(0);>