I have restored a old car radio for a freind and want to check the aligment. the Riders manual I have shows a trimmer cap that the radio don't have (C406). also the radio has a sensitity controll, but it don't say how to adjust it. Any one have a better manual?

:I have restored a old car radio for a freind and want to check the aligment. the Riders manual I have shows a trimmer cap that the radio don't have (C406). also the radio has a sensitity controll, but it don't say how to adjust it. Any one have a better manual? Forgot to say the radio model is C4608
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R-401 Cathode resistor. Adjust for 15 volts. Make sure the radio does not distort (overload) with a strong air signal. If so, back off a little. C-406 if not there, may have been eliminated production change. May check to see if there is a fixed capacitor there.

:R-401 Cathode resistor. Adjust for 15 volts. Make sure the radio does not distort (overload) with a strong air signal. If so, back off a little. C-406 if not there, may have been eliminated production change. May check to see if there is a fixed capacitor there. There is a fixed capacitor in that location, so i guess just skip that step, I can't get more than 1 to 5 volts adjustment by adjusting R-401, was the reading supposed to be 1.5?
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Yes, 1.5 volts would seem correct. The lower the voltage the more sensitive. Use the car antenna fully extended. tune to a strong station. Make sure the front end does not overload.