Zamieszanie z GPS - tydzień 0 ?
Na ukmicrowave było kilka postów na ten temat. Oto pierwszy z nich:
For those of us reliant on GPS based frequency standards and location systems, there is an upcoming event that may upset some GPS engines.

GPS week numbers only go up to 1024 and we hit another ‘week zero’ event on 6th April this year.

This can and does cause some older GPS engines to become rather upset. Some completely loose lock, some may still produce 1PPS etc but output the wrong date and time
Many of these recover at week 1 but that is not guaranteed.

Some testing has been done by a colleague on a number of GPS based systems using a locally generated GPS signal set that simulates the week zero signals.
A number of older GPS engines have failed this test and the frequency standards associated with them have been shown to go into holdover and start to drift....
Amongst the ones likely to fall over are the Rockwell chipset widely used by amateurs. The exact model with 10KHz (Jupiter) out has not been confirmed but pretty much all of the related models, used in a number of GPS disciplined oscillators, fell over.
The Jupiter in my old RUH system already needs a poke of serial data at start-up, I believe to correct a previous timestamp rollover. I guess it may need a different one soon. Sad smile
I am aware that if all else fails, UBlox GPS engines have been successfully used in the RUH design standard in place of the Jupiter, as some Ublox engines can be programmed to output the required 10KHz instead of 1PPS
All (slightly older ) UBlox modules that have been tested were unaffected so it is likely that newer ones will be OK too,

Some older Rapco GPS standards fail the Week Zero test which makes them think they are the best part of twenty years younger. Their recovery into week 1 is not certain.

I am aware that at least one model of these has an internal firmware week counter which will rollover in July if I recall, further complicating matters
I also have one of these and its useful life is now in question. Sad smile

The Trimble Palisades out there are an unknown quantity.
I will try to get one tested. I use one of these with a VE2ZAZ system and so does GB3CSB

73's de Staszek SP6GWB


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