UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

crackle · 13th Feb 2018, 1:32 pm

I am restoring one of these radios at the moment. (not the one seen in the Museum) https://www.radiomuseum.org/r/kolste...iversal_3.html
This one was wired up in a different way to the circuit diagram, the red mains wire went to chassis after the filter choke and the heater dropper resistor was not wired as per the diagram.

Click image for larger version

Name: KB 381 circuit1.jpg
Views: 156
Size: 92.9 KB
ID: 157296

I am in the process of returning it to how it was drawn on the circuit diagram.
There are 2 TCC type M .01uf mica caps, C4 for aerial earth to chassis and C3 across the mains, after the 2 series filter chokes.

Click image for larger version

Name: TCC type M cap.jpg
Views: 145
Size: 60.2 KB
ID: 157295

Both caps test OK for capacitance and show zero leakage current at 370v DC test voltage and with the AVO switched to 50uA range.

What is the feeling about returning these original capacitors to the circuit to carry on what they were intended to do.

thanks
MIke

13th Feb 2018, 1:32 pm	#1
crackle Rest in Peace Join Date: Mar 2011 Location: Basildon, Essex, UK. Posts: 4,100	KB 381 5 valve AC/DC superhet I am restoring one of these radios at the moment. (not the one seen in the Museum) https://www.radiomuseum.org/r/kolste...iversal_3.html This one was wired up in a different way to the circuit diagram, the red mains wire went to chassis after the filter choke and the heater dropper resistor was not wired as per the diagram. I am in the process of returning it to how it was drawn on the circuit diagram. There are 2 TCC type M .01uf mica caps, C4 for aerial earth to chassis and C3 across the mains, after the 2 series filter chokes. Both caps test OK for capacitance and show zero leakage current at 370v DC test voltage and with the AVO switched to 50uA range. What is the feeling about returning these original capacitors to the circuit to carry on what they were intended to do. thanks MIke