What value are the 2 Capacitors [C3] connected to the wave change switch to ground.
The component list on the circuit diagram show C3 as a dual fixed padder, no valve shown.
Also, what does the connection on the input signal grid of the det/osc, [from the oscillator circuit] consist of

This is what is called a gimmick capacitor. Just a turn or three of wire from the osc wrapped around the RF input wire. It is important for providing a small amount of negative feedback for stablizing the shortwave band.

:Also, what does the connection on the input signal grid of the det/osc, [from the oscillator circuit] consist of
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:This is what is called a gimmick capacitor. Just a turn or three of wire from the osc wrapped around the RF input wire. It is important for providing a small amount of negative feedback for stablizing the shortwave band.
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::Also, what does the connection on the input signal grid of the det/osc, [from the oscillator circuit] consist of
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Thanks for that rghines. I guessed it was some sort of feedback or neutralization.
As for the first part of my question I should have added the Zenith part number which looks like #22-558
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Here's a page from an application book on converters concerning neutralization. Sorry don't have the book title, its been 15 years ago when struggling with a problem with Zenith 8S154 console.

:Thanks for that rghines. I guessed it was some sort of feedback or neutralization.
:As for the first part of my question I should have added the Zenith part number which looks like #22-558
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:Here's a page from an application book on converters concerning neutralization. Sorry don't have the book title, its been 15 years ago when struggling with a problem with Zenith 8S154 console.
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::Thanks for that rghines. I guessed it was some sort of feedback or neutralization.
::As for the first part of my question I should have added the Zenith part number which looks like #22-558
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::Re Zenith part # 22-558.Mystery solved.When all else fails clean up the workshop. Swept out from under the workbench a dual padder mounted on a metal bracket for chassis mounting, with the part number clearly embossed on it. Although it is called a dual fixed padder, it consists of two variable caps, 1.2nf, and 3.75nf.Can I assume that the larger one is for the lower of the two short wave bands ?
::Thanks
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Stands to reason the 3.75nF padder would be for the Police band, while the other for the shortwave band. Alignment procedure makes no mention of how to adjust them. I assume they were originally fixed padders designated C3 on Rider schematic. If you're experienced with alignments improving the tracking should be possible.
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:::Re Zenith part # 22-558.Mystery solved.When all else fails clean up the workshop. Swept out from under the workbench a dual padder mounted on a metal bracket for chassis mounting, with the part number clearly embossed on it. Although it is called a dual fixed padder, it consists of two variable caps, 1.2nf, and 3.75nf.Can I assume that the larger one is for the lower of the two short wave bands ?
:::Thanks
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