Just got our group PA28 back from its annual with a new Icom A220 fitted in place of our King box. Very modern, large clear display and good sound quality. Went for a first flight with it and quite impressed. When I landed I thought I'd try switching it into 8.33 mode - so into the setup menu select 8.33khz but now it's in set 8.33 I can't seem to get any 25khz frequencies to come up on the display, they just don't exist! Put in Cumbernauld 120.605 fine but then tried Scottish 119.875 & it wasn't there. What am I doing wrong?