[time-nuts] The Demise of LORAN (was Re: Reference oscillator accuracy)

[J. Forster]

My first contact with LORAN was at the bankrupcy of a local company that
supplied tracking and location services for trucking companies. The trucks
had a receiver that sent data back to home base via two-way radio and home
pbase computed positions. I was only nteresteed in buying their mimis.

In the early 80s I was playing around with uP (8085) based LORAN receivers
(Made by Appelco/Raytheon). One version read out time differences and a
more advanced (w/ 2x 8085s) version read out Lat & Long directly. Either
would pinpoint my location to 100' class. It was accurate navigation in a
two-way radio sized box.

There were, of course, no map or chart displays. Imagine what 20+ years of
development would have brought.

-John

=============


> Bruce,
>
> I agree with your calculation and conclusion, as far as commercial
> consumer
> GPS receivers are concerned.
>
> A data sheet that was linked in a previous post for an aviation-grade
> commercial GPS receiver indicated resistance to signals -30dBm at the
> receiver input. That is quite considerable, and much better than the
> hand-held consumer units (by 30dB?)
>
> I would expect planes and other potential "high value targets" to have
> receivers of similar performance.
>
> I don't disagree that it would be fairly easy to disrupt the consumer
> devices, but other than a few missed appointments and frustrated gadget
> freaks, and the occasional emergency vehicle not finding its way to the
> scene of an accident, that would be more of a problem) I am not too
> worried
> about the consequences of that.
>
> The thread started with the loss of the LORAN system, and nobody (maybe I
> am
> going out on a limb here) ever used a LORAN receiver in his car to find
> the
> nearest restaurant :)
>
> I think the people who should complain the most about the loss of LORAN
> are
> the boaters, but they are the one who embrassed GPS the first and are it's
> biggest advocates!!! I know, I live on the coast of Florida.
>
> Didier