This document is just what I was looking for, it´s very useful, it contains adjustment procedures for the final stage of the power amp and also
has a complete wiring diagram and description of the main semiconductors used in the design.
Dear Sirs,
Thank you for the fast support, the manual does provide all necessary information to repair the radio. All schematics are in a good quality for reading.
The manual fits 100% to my requirements as a technican.
Kind regards Thomas
the big video recorder format s-vhs many features delicate in loading system of the cassette. Such machines are no longer manufactured, it would be too expensive.
Text excerpt from page 22 (click to view)
QT-CD180H/QT-CD180W
� Focus failure.
Does the optical pickup move up and down when the disc is removed ? Yes Check as stated in item "FOCUS SERVO SAWTOOTH WAVE FAILURE".
No
Is the following waveform output at the pin 62 (FEI) of IC802 when the disc is set ? Yes
pin 62 (FEI)
No
Check the periphery of IC801 and BI801/CNS801. Is it normal ? Yes
The optical pickup is faulty.
pin 86 (FOO) pin 63 (SBAD)
Is the waveform shown above input at the pin 63 (SBAD) of IC802 ? Yes
No
Check the pattern between pin 13 of IC801 and pin 63 of IC802. Check the periphery of IC801 and BI801/CNS801.
IC801 is faulty.
� Focus servo sawtooth wave failure.
Is sawtooh wave output to the pin 66 (FOO) of IC802 ? Yes IC802 is faulty.
No
1.5~2.5sec
Is +8.1V applied to the pins 21 and 22 (VCC) of IC803 ? No Yes
Check the PWB pattern of IC803.
Is sawtooth wave obtained between pins 17 and 18 of IC803 ? Yes
No
Check the PWB pattern of IC803.
1.5~2.5sec
Is sawtooth wave obtained between pins 3 and 4 of BI801/ CNS801 ? (as shown above) Yes
Check the PWB pattern between BI801/CNS801 and IC803. No
BI801/CNS801 connection failure or optical pickup failure.
