12-10-2021, 07:40 PM
You can do a simple test to see if the oscillator is off frequency or the problem is the IF
Confirm the the local oscillator is operating at the right frequency by listening with your digital receiver. For example, set the dial on your Philco to 600 kc. With the correct 470 kc IF, the osc should be running at 600 + 470 = 1070 kc.
Tune your digital receiver to 1070 and place near the osc tube. You should hear a strong carrier. If not tune the Philco dial slightly until you hear the osc signal. If the Philco dial reads at or near the proper 600 kc, then the osc is at the right freq and the IF is off.
If the dial needs to be tuned 40 kc from the 600 kc dial mark to hear the signal at 1070, then there is an oscillator problem.
Confirm the the local oscillator is operating at the right frequency by listening with your digital receiver. For example, set the dial on your Philco to 600 kc. With the correct 470 kc IF, the osc should be running at 600 + 470 = 1070 kc.
Tune your digital receiver to 1070 and place near the osc tube. You should hear a strong carrier. If not tune the Philco dial slightly until you hear the osc signal. If the Philco dial reads at or near the proper 600 kc, then the osc is at the right freq and the IF is off.
If the dial needs to be tuned 40 kc from the 600 kc dial mark to hear the signal at 1070, then there is an oscillator problem.