ATC transponder codes

[Viscount Sussex]

Hi

Here we go again!

Can anybody please shed any light on the various codes? Is there a list anywhere I can have a look at, apart from the obvious sq's like 7700, 7600 and 7500?
Lets say 7601. Any clues?


Thanks.

[The Truth]

UK SSR allocation plan is contained within the UK AIP - online version at www.ais.org.uk (need to register) - in the EnRoute section ENR 1-6-2-3

[Viscount Sussex]

The Truth

Thank you very much.
I had already registered, but I hadn't thought of looking there.
Brilliant.
Cheers.