1g-102 rf generator

I built the demodulator probe and placed it between the generator and the scope.It cleaned up the signal and I could see a good sign wave. When I turn the variable capacitor I see no change in the frequency. The output for the af 400 hz is ok. Can anyone lead me in the rifgt direction to repair this thing???

Is this what you are asking about?

http://www.heathkit.nu/heathkit_nu_IG-102.html

Just to help identify it.

Yes that is the one. I have checked all the resistors and they are good. The schematic you have shows the plate resistor 4.7k and that is what is in the circuit. My schematic shows a 10 k. I don't think that is the problem.

Hopefully someone familiar with the unit will chime in.

I will keep an eye on the posts. Thanks a lot.

I read up on how to read freq. on the scope. With the scope set at 1micro sec. ch1 , 20 mil. Volts
RF generator set at band A , Coarse attenuator at high, FR attenuator at high.
Pointer at 10, I see one cycle
Pointer at 20, I see two cycles
Pointer at 30, I see three cycles.
When I turn the variable attenuator down at one point I lose the signal.

I don't quite understand what you are trying to describe with what seems like as few words as possible. I am inferring though, that you are expecting the audio output of the IG-102 to change with the dial setting? It won't. Only the RF will, but the modulation that you would see on the scope with a demodulator probe should remain a 400 Hz sine wave, whatever the RF carrier frequency you set.

The wave form I see is a good sign wave,but it changes as I turn the variable capacitor to the settings of 10,20,30. I connected my fluke 79 and checked the frequency and it is 357 hz. It should be 400. It reads the same with the scope connected. All this I did without the demodulation probe. I checked the out put for the RF using a radio and finding the zero beat. I have the construction manual and I followed the calibration section. They all were good except the f band. I question my work. I only hear the hz at one place on the dial. If I understood the manual correctly I should hear it across the band.