The case of the failing FT-817 S-meter

This case took me several hours and since I didn't have time to solve this it was something that kept my mind busy the whole saturday. I think it is interesting enough to write a post about it.

The case or problem, or we better call it the challenge: S-meter not functioning on LSB/USB on any band except for some really strong signals S-meter shows only 1 or 2 bars. RF gain fully open. RX is good, antenna is good (checked with another radio). S-meter does function on FM and PKT mode.

I did not use the radio for a long time and this problem occured to me after I replaced the speaker. First I was afraid I broke something (you never know). Soon it became clear to me it has to be something wrong in the radio settings, but what? Since I used the radio only for digimode the last half year it could be related to that, and it did....AGC was turned off in the menu. When I switched it to automatic the S-meter came alive and everything was normal again.