04-10-2022, 08:26 PM
I'm working on a 38-12 that has two modifications, one of which I don't understand.
Visit http://www.nostalgiaair.org/Resources/236/M0013236.htm for the schematics.
The modification I'm seeing is coming off the center terminal of the volume control. It consists of a 50pF mica in parallel with a 400kohm resistor which then connects to the .01 mfd cap that is shown on the schematic. After changing the filter caps and removing the modification in power supply, I turned the radio on. It works about as well as you would expect for leaky caps and many way out of tolerance resistors. I tuned in a station and listened to it then bypassed the modification. As far as I could tell, there was no difference between the two.
Does anyone have an idea as to what this modification as supposed to do?
Visit http://www.nostalgiaair.org/Resources/236/M0013236.htm for the schematics.
The modification I'm seeing is coming off the center terminal of the volume control. It consists of a 50pF mica in parallel with a 400kohm resistor which then connects to the .01 mfd cap that is shown on the schematic. After changing the filter caps and removing the modification in power supply, I turned the radio on. It works about as well as you would expect for leaky caps and many way out of tolerance resistors. I tuned in a station and listened to it then bypassed the modification. As far as I could tell, there was no difference between the two.
Does anyone have an idea as to what this modification as supposed to do?
Sometimes I wonder whether the world is being run by smart people who are putting us on or by imbeciles who really mean it.
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