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wire routing thoughts
#4

You definitely do not want to lengthen or change the position of wires, especially in the band switch area. 

At short wave frequencies, a length of wire acts as an inductor or coil and placing two wires next to each other forms a capacitor. At VHF, one inch of wire may change the tuning of the circuit completely. So at these frequencies you are changing the actual circuit design by changing the physical wiring.

At audio frequency, this effect is not as significant, but bundling a low level audio amp grid circuit wire with filament wiring will definitely cause hum. Placing the same grid wire next to plate wiring of the following stage will cause it to go into squealing oscillations.

The original wiring was placed as it was for a reason, and the engineers involved spent a great deal of time and effort getting it right. It may not be pretty, but the wiring layout was done for best operation and performance. 

That's why the repair info says to duplicate it as closely as possible.


Messages In This Thread
wire routing thoughts - by jcassity - 04-01-2017, 11:00 AM
RE: wire routing thoughts - by morzh - 04-01-2017, 11:26 AM
RE: wire routing thoughts - by David - 04-01-2017, 02:07 PM
RE: wire routing thoughts - by Mondial - 04-01-2017, 07:29 PM
RE: wire routing thoughts - by jcassity - 04-01-2017, 10:07 PM
RE: wire routing thoughts - by Arran - 04-02-2017, 12:52 AM



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