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Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!ihnp4!inuxc!pur-ee!uiucdcs!trsvax!levy
From: levy@trsvax.UUCP
Newsgroups: net.aviation
Subject: Re: IFF/SIF Modes
Message-ID: <59200006@trsvax.UUCP>
Date: Tue, 11-Dec-84 10:34:00 EST
Article-I.D.: trsvax.59200006
Posted: Tue Dec 11 10:34:00 1984
Date-Received: Sat, 15-Dec-84 02:24:41 EST
References: <1200006@uokvax.UUCP>
Lines: 9
Nf-ID: #R:uokvax:1200006:trsvax:59200006:000:204
Nf-From: trsvax!levy    Dec 11 09:34:00 1984

(from trsvax!levy)

Mode 3 can be used with or without altitude encoding.

Mode 1, I believe, is left over from an earlier system and only allows a
two-digit squawk code.

Mode 2 is used by the military.