29-06-2011, 03:57 PM
Hello John
Please find attached a PDF copy of the service information for your National TC333G, from the 1978-79 volume of Radio and Television Servicing. The fault sounds like there is a fault with the RF amplifier in the tuner, but there is a vision IF preamp TR101 between the tuner and the IF amp IC101. It may be worthwhile checking the voltages around TR101 first to see if is amplifying and the voltages on the tuner and the AGC line to the tuner and at IC101.
Regards Stan.
Please find attached a PDF copy of the service information for your National TC333G, from the 1978-79 volume of Radio and Television Servicing. The fault sounds like there is a fault with the RF amplifier in the tuner, but there is a vision IF preamp TR101 between the tuner and the IF amp IC101. It may be worthwhile checking the voltages around TR101 first to see if is amplifying and the voltages on the tuner and the AGC line to the tuner and at IC101.
Regards Stan.
