FM immunity only applies to VOR Navigation sets.
Bookworm is correct but for completeness probably a good idea to add that you can even fly within class D with non immune stuff in VFR and even IFR but you will need prior permission for that from ATC.
The 8.33kHz spacing has nowt to do with FM immunity.
The filters which were intially heralded as the saviours of old sets are under scrutiny. They were/are very expensive so most people who needed FM immunity did choose to go the whole hog and got a Garmin 430 which addressed the issue nicely and also allows 8.33KHz spacing and throws in a GPS navigator at the same time.
FD
Last edited by Flyin'Dutch'; 8th Aug 2003 at 01:05.