[Eliot Ness]

Turn on an operating radio tuned to 1455 kc next to your Philco. Tune the Philco up and down around 1000 Kc and if the osc/mixr is working, you should hear a rushing or squealing in the other radio.

The principle behind this is if the IF is 455 kc and you tune to 1000 kc on the dial, the Oscillator will operate at 1455 kc. You should then be able to hear the signal on another radio tuned to 1455 kc.

Edit: If I looked at the right schematic your Philco has an IF of 455, but you might want to double check.