30-01-2018, 01:55 PM
Mike, without the numbers, this is what I did:
You say that the tuning indicates 1600m when tuned to R4 so I calculated the local oscillator frequency for R4.
Then without touching the RF tuning, calculated what the signal frequency would be if you changed the IF from 120kHz to 130kHz, as you proposed.
This would be 188kHz/1600m which is exactly what the tuning scale says.
Therefore, if you retune so that the scale says 1500m, you should find R4, which is what you wanted.
Does that help?
You say that the tuning indicates 1600m when tuned to R4 so I calculated the local oscillator frequency for R4.
Then without touching the RF tuning, calculated what the signal frequency would be if you changed the IF from 120kHz to 130kHz, as you proposed.
This would be 188kHz/1600m which is exactly what the tuning scale says.
Therefore, if you retune so that the scale says 1500m, you should find R4, which is what you wanted.
Does that help?
