Philco radio cap problem

[radio nut]

Originally Posted by rollei35guy

Looking at the schematic I believe this set has a 'floating ground'. That is the ground is not on the chassis but at several points that are tied together. Sometimes a solder lug or a tube socket lug, or a combination. There is usually a capacitor and/or high value resistor to chassis to bypass ac line noise. One side of the secondary of the speaker transformer runs to chassis ground too.

These are a bit safer than the notorious hot chassis models. Of course if that capacitor to chassis shorts then all bets are off. There are special caps for that purpose.

Look at the chassis and try to find where the points for this floating ground are.

Are you using an isolation transformer? Recommended regardless of the set.

The speaker secondary does not currently go to ground. With the original speaker missing the output trans. is just hanging. Could this be part of the problem?