This page is dedicated to my Icom 821H, which is a great VHF/UHF satellite and weak signal rig. It’s not without it’s quirks, so this will serve as a reference for myself and anyone else who is looking for info about operating and repairing this radio.
Block Diagram: http://kk4fem.com/files/ic821h-block-dia.pdf
Display Unit: http://kk4fem.com/files/ic821h-disp.pdf
Main Unit: http://kk4fem.com/files/ic821h-main.pdf
PLL Unit: http://kk4fem.com/files/ic821h-pll.pdf
RF/PA Units: http://kk4fem.com/files/ic821h-rf-pa.pdf