[Elecraft] April 6th GPS Reset

[Dave Cole (NK7Z)]

How is HAARP involved in this conspiracy, it must be!

73s and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Technical Specialist
ARRL Volunteer Examiner
ARRL OOC for Oregon

On 4/3/19 12:30 PM, Fred Jensen wrote:
> The week number register is in the hardware aboard the GPS satellites, 
> although receivers usually read and store it too.  Each rollover is a 
> "GPS epoch," epoch being a term used by space travelers, astronomers, 
> and other folk dabbling in space-ish things to confuse the rest of us. 
> The first epoch ended in Aug 1999 ... 1024 weeks is 19.<mumble> years. 
> We are approaching the end of epoch 2.  In 1999, a few of the early GPS 
> receivers hit the WNRO [week number roll over] and thought it had become 
> 1980 again.  Using a GPS receiver to discipline the K3 involves the 
> clock signal and unless you are using your very very old receiver to 
> tell you what the current date is, the WNRO will have no effect.
> 
> Early in the first GPS epoch, it was discovered that the "civilian" 
> signal was yielding somewhat better accuracy than the US Dept. of 
> Defense had planned, and they implemented SA or Selective Availability 
> to perturb the satellite clocks making it appear that you were moving 
> around randomly in a 100-200 m area when you were in fact stationary. 
> This would affect the clock signal at the receivers and thus the 
> "discipline" applied to the K3.
> 
> It wasn't very long before a number of entities, including manufacturers 
> and the US Coast Guard ... found ways to get around SA.  One is 
> Differential GPS which places stations at very carefully surveyed 
> locations, monitors their GPS reported positions, and transmits the 
> errors.  The DGPS receiver uses the errors to correct its own GPS 
> position.  If you have the new synthesizer for your K3 [or a K3s], you 
> can hear and decode the DGPS signals, they're 100 bps MSK in the 284-458 
> KHz range and have a distinctive signature on a P3.  The US DoD gave up 
> on SA long ago but the DGPS stations remain, or at least did the last 
> time I checked.
> 
> One GPS conspiracy theory posited that there was a "back door" into the 
> satellites put there by another country [which we'll leave nameless] 
> which, when activated, would be used to cause all the aircraft in the 
> air to converge on one point and create a great conflagration. 
> Conspiracy theories have a half-life and fortunately this one was fairly 
> short, similar to the half-life of disco and leisure suits. [:-)
> 
> 73,
> Fred ["Skip"] K6DGW
> Sparks NV DM09dn
> Washoe County
> 
> On 4/3/2019 11:24 AM, na5n at zianet.com wrote:
>> Fred Jensen writes:
>>
>>> Eventually, the 10-bit register holding the week number will overflow 
>>> and reset to zero. That's all that's happening, it happens every 
>>> 1,024 weeks, the first was in Aug 1999.
>>
>> The GPS reset has been the source of hysteria in various circles, 
>> including exhaustive discussions on the various private pilot and 
>> drone forums, since most aircraft and drones use GPS for real time 
>> positioning and navigation while in flight.
>>
>> In short, when this happened in 1999, changes were made to lengthen 
>> the roll over period to beyond our lifetime.  The April 6 rollover 
>> only effects older GPS devices with the 10-bit registers.  Basically, 
>> every GPS embedded device made in the last 10-15 years or so will not 
>> be affected - only the first generation devices.
>>
>> There are absolutely no warnings or cautions on the websites for 
>> Garmin, Magellan, or Trimble showing it is a non-issue for their GPS 
>> devices - not even mentioned.  The FAA has a list of the very few GPS 
>> devices used in older private aircraft that could be effected, only if 
>> in flight when the rollover occurs.  With 10,000+ people in the air at 
>> any moment, there would be a huge air of caution by the FAA and 
>> airlines if the rollover had any chance of effecting the GPS devices 
>> now in use.  In this case, "Silence is golden."
>>
>> 73, Paul NA5N
>>
> 
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