Hey there from the side of the road in the forest offa cell booster. I can't recall the dealer mode setting in the Icom software but should be under Options, otherwise it's set in firmware/codeplug.
Edit: look in my other posts, a helpful gentleman uploaded some VCO files for these radios that might be helpful.
Have you attempted the front panel programming? Posting here just as much for you as my repeated reference,
This PDF for the F1000T can be found online, however much of it doesn't apply to the FC121/221. In short,
- hold P0 and UP while turning on power
- "DEALER"
- enter password: P1, P0, pwr, P3, P0, P2
- "SETMODE"
- press P0 to enter FPP mode
- use the P-keys and arrows to browse around, you'll have to experiment here but can edit tx/rx freq and tones on existing channels only
- so my bank 1 (default for editing) is "BLANKS", a pile of simplex freqs that get repurposed on the road. Can't set channel names so bring a pen!
- when done fiddling, power OFF to save changes
G'luck,