This service manual of the old video cassette recorder VT-LC50EM is very good readable even the tiniest numbers (i.e. IC-pins). The circuits are very clear. Many details of the schematic are very good described but in GERMAN language. Many schematic details - but complete at all. Common background information of several details are enclosed and physical knowledge of the TFT liquid crystal display for example. The manual lacks PCB drawings. If you understand german I would recommend this manual for you.
Text excerpt from page 13 (click to view)
3. The base and handset cannot be connected.
Check whether the base is able to set in the test mode. OK Check the TX POWER and the TX FREQUENCY on the base unit. OK Press SKIP key twice, check whether the TXD is output from Pin 48 of IC3. OK Check whether the TXD is output from MOD POINT (See page 28). OK Check whether the handset is able to set in the test mode. OK Check the TX POWER and the TX FREQUENCY on the handset unit. OK Press "3" key, check whether TXD is output from Pin 40 of IC601. OK Check whether the TXD is output from MOD POINT (See page 30). OK Place the handset on the base to charge about 5 seconds, then try connecting again. NG Check R620 and the handset RF unit. NG Check IC601 and its peripheral circuit. NG Check the handset RF unit. NG Check IC604 and its peripheral circuit. NG Check R7, R21 and the base RF unit. NG Check IC3 and its peripheral circuit. NG Check the base RF unit. NG Check IC5 and its peripheral circuit.
