All voltages look OK on this CGE KL-60 or RCA A-24. I get three local AM stations. Oscillator is working. Negative voltage on pin 5 of the 6SA7. I get good modulated tone from sig gen when applied to pin 8 of 6SA7. Lots of audio when I touch pin 2 of the 6SQ7 and middle terminal of the volume control with audio probe of sig gen. Very little (if any) tone at grid of the 6SK7. Checked resistors, replaced coupling capacitors. I assume my problem is in the detector stage. Replaced the detector tube as well. Any suggestions?

This radio has an RF amplifier front end. By injecting a signal to the 1st detector tube (6SA7)and getting a good tone, the problem would seem to be the RF amplifier not working. Check the voltages on the RF tube. I think the cathode is at ground. I think there is also mica capacitor that feeds the signal to pin 8 of the 6SA7 from plate of RF tube. The RF tube is connected to the AVC line. Check along this line for the negative voltage pin 6

Thanks for the email, not sure which tube pin 6 you are referring to? I do have plate and screen voltage on the rf amplifier tube.

:This radio has an RF amplifier front end. By injecting a signal to the 1st detector tube (6SA7)and getting a good tone, the problem would seem to be the RF amplifier not working. Check the voltages on the RF tube. I think the cathode is at ground. I think there is also mica capacitor that feeds the signal to pin 8 of the 6SA7 from plate of RF tube. The RF tube is connected to the AVC line. Check along this line for the negative voltage pin 6
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Don't have the print to your radio. Forget about pin 6, my error. Check the primary and secondary of the antenna coil. The AVC is normally connected to the secondary.