Heya Mizuez, ta for the response.
I've been using the backup system mostly as I'm trying to simulate a viper with limited avioincs etc.. For instance i loaded training 10 and changed the GPS coordinates for steerpoint 5 to KIMPO (083x) instead of landing at KUNSAN. Flew to KIMPO and then went radial 20 degress for 31 miles and ended up over Mandumi. Just mentioning this as I've been a long time Falcon flier, but have forgotten A LOT of stuff, but I do remember some stuff. Anyhoo as you mentioned the kneeboard mentions 83x as the TACAN for both Mandumi and KIMPO. If I have it set to 83x and I'm outside of the 30 mile range from KIMPO I can land at Mandumi (but with no conversation from Mandumi tower) however when i do land I don't get yelled at for not waiting for clearance etc if I'm on the 83x. Now the AF manual does have Mandumi at 1Y?? WEIRD, but I can try using the ICP with Iy and see if it works. The only prob is as I mentioned, I'm trying to simulate a Divert Field experience where I might not have access to the ICP and DED in which case I have to use the backup and it seems no matter what channel i put into the backup TACAN (left console) and no matter what band Y or X, I just can't get anyone from Mandumi's tower to speak to me. It's sooo Infuriating lol. I haven't even tried the airstrips yet hehehe
I'll try a TE with a take off from mandumi, and fiddle as you mention above. But did you ever get full conversations from Mandumi's tower without it being your start base?