[time-nuts] GPS Selective Availability. Is it On or Off?

Rob Kimberley time.bandit at btinternet.com
Sun Mar 12 14:22:39 EST 2006

SA was turned off in May 2000, and has stayed off since. The US Mil have
other ways of denying access to C/A on a local basis, rather than the global
degradation that S/A gave. The main reason for this is that US MIL have
mandated that all future procurement of GPS will be using SAASM Direct P/Y
hardware. This equipment has enhanced black key security features to the
existing P/Y hardware, plus the ability to acquire without the need for C/A
(C/A was designed originally as purely the coarse clock to enable P code).
Now, in times of conflict, all they need do is deny C/A in that area. The
new hardware can run without C/A, come up cold without C/A, but the enemy
and anyone in that geographic area is denied service. 

This info is in the public domain. FEI-Zyfer (formerly Odetics)
www.fei-zyfer.com whom I used to work for manufacture SAASM GPS timing

Rob K 

-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Magnus Danielson
Sent: 12 March 2006 18:58
To: time-nuts at febo.com; rexa at sonic.net
Subject: Re: [time-nuts] GPS Selective Availability. Is it On or Off?

From: Rex <rexa at sonic.net>
Subject: Re: [time-nuts] GPS Selective Availability. Is it On or Off?
Date: Sun, 12 Mar 2006 09:58:25 -0800
Message-ID: <21o812lqml7dl24s3ijbnf2kcj1tkh480o at 4ax.com>

> On Sun, 12 Mar 2006 12:36:12 -0500, Chuck Harris <cfharris at erols.com>
> wrote:
> >SA was turned off to allow the troops in Desert Storm to use civilian 
> >GPS units (there was a critical shortage of military P-band units)
> >
> >It has never been turned on since.
> >
> >-Chuck Harris
> Where did you get that notion? Desert Stom was 1991, wasn't it? What 
> happened in 2000, like this web page mentions?
> http://www.cycc.org.uk/news/gpssa.htm

The SA was enabled again after Desert Storm, and it was not until the
presidential order that it was turned off again for a longer period of time.

See this page if you don't beleive me:


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