Channel Master Radio 6436-A

This radio is from the era when the manufacturer would proudly list the number of transistors.

On the back of this radio there is a model number tag listing:
15 Transistors
11 Diodes
1 Thermistor

The electrolytic capacitors appear to have 1967 and 1968 date codes.
Forty plus years old!

Inside view of Channel Master radio model 6436-A.

I only had one problem develop with the radio during the 16 years I have been using it. The audio would cut out intermittently and I would tap on the radio or move the band selector switch and the audio would return.
It got worse over time I finally took the time to find the problem.

I discovered a bad resistor solder joint. It appears the resistor was changed after the radio was assembled.

Channel Master radio 6436-A schematic, small view

A quirk of this radio is if you install batteries and plug the radio into an ac wall outlet. The built in power supply will apply about 8 volts to the batteries.

I discovered this about 3 weeks after installing alkaline batteries and finding them leaking in my radio.
Maybe the old carbon batteries were tolerant of being charged.

This problem can be eliminated by installing a diode to prevent the batteries from being charged by the ac power supply.

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