I have a Philco am-fm radio, the am works fine, but the fm section sounds distorted,like it is overmodulated. once in a while it will just pop in and work fine.I have whent though the riders trouble shooting sections, when i get to section 4 it says the oscillator test, that it should read -1 to 1.5 volts, and my set reads positive, was this just a mistake in the manual? any ideas on this problem ?

Hi,
I would look at the caps in the oscilator circuit, as well as the bypass caps- especially the paper caps. I suspect there sone just begining to short, and that pop that you are hearing is when the short burns apart.
You may also have grid resistor that has shifted value, check the cap that is most likely across the resistor too- as this is the most likely culprit.

Also check condition of the solder joints inthe circuit, it could be that is the cause of the problem. A can of "cold shot" sprayed on the terminals one at a time, as well as the ends of the caps where the leads are can often reveal the culprit faster than anything.

This is assuming the tube itself tests fine.

: I have a Philco am-fm radio, the am works fine, but the fm section sounds distorted,like it is overmodulated. once in a while it will just pop in and work fine.I have whent though the riders trouble shooting sections, when i get to section 4 it says the oscillator test, that it should read -1 to 1.5 volts, and my set reads positive, was this just a mistake in the manual? any ideas on this problem ?