EH Scott Radio Enthusiasts

The Fine Things are Always Hand Made

A little bit of past progress. 

My Philharmonic remote chassis S/N BB106 was intended to be a spare chassis, but the more I thought about it became my primary set for the cabinet. 

After recapping the chassis was brought up with a variac B+ was only 34 vdc, not a good sign. You can see the thermal damage in the photo below. Melted the insulation on one of the wires going to the volume control.

Further troubleshooting confirmed that one of the 1k resistors going into one of the IF cans was shorted at about 130 ohms. Don't think I have seen a shorted resistor. Replacement of the resistor bought the set to life.

 

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Look out for the rubber wires that pass thought the chassis from the IF coils to the variable capacitors under the chassis, a good replacement for this is silicone rubber insulated wire, the type that is used on test leads is good, and it looks like the old rubber type, 

unfortunately the bottom halves of the caps will have to come out, to fit these wires meaning you will have to align the IF when done.

Those 1k resistors burn and either go open of change value due to shorted bypass caps across them. The Philly I am currently working on had one totally burned up due to a shorted cap. I check all of them when I do a restoration, a <very> common failure.

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