Re: [time-nuts] What cut do I have?

Those 32KHz watch crystals are very flat in the vicinity of the turnover. They don't age well. But if all you need is temperature stability and you can correct for aging a nice little electric heat pump (heats and cools) to keep the crystals at around the 25C inflection point might be

Re: [time-nuts] What cut do I have?

Hi Any crystal in the vicinity of turnover point is going to be pretty flat. That relates directly to the way turnover is defined. There are some exceptions (10811), but the vast majority of OCXO designs operate the crystal very near the turnover point. The whole chill it down approach was

[time-nuts] GPS at 60,000 feet

How to check if a GPS works at 60,000 feet: send up a balloon: The good folks at Duke University sent a uBlox based GPSTCXO up there, and it worked at max balloon altitude which was about 60,000 feet. The ambient temperature must have been around -50C up there, and maybe down to -67C

Re: [time-nuts] GPS at 60,000 feet

On 1/29/2013 1:55 PM, saidj...@aol.com wrote: Note that this is higher than the older GPS would support, due to the new Wassenaar speed/altitude limits. What are the current limits? UBlox is Swiss, and therefore subject to Wassenaar. Are there any GPS chip makers in China (or ?), who wouldn't

Re: [time-nuts] GPS at 60,000 feet

Ublox limits it to 164,000 feet or 50,000m. Pretty much higher than any ballon would go I think. Bye, Said Sent From iPhone On Jan 29, 2013, at 13:24, Mike S mi...@flatsurface.com wrote: On 1/29/2013 1:55 PM, saidj...@aol.com wrote: Note that this is higher than the older GPS would support,

Re: [time-nuts] GPS at 60,000 feet

Yes, indeed. Scientific balloons get up to about 125,000 ft, 38 km max. David On 1/29/13 5:39 PM, Said Jackson wrote: Ublox limits it to 164,000 feet or 50,000m. Pretty much higher than any ballon would go I think. Bye, Said Sent From iPhone On Jan 29, 2013, at 13:24, Mike S

Re: [time-nuts] GPS at 60,000 feet

Hi Said, On 01/29/2013 11:39 PM, Said Jackson wrote: Ublox limits it to 164,000 feet or 50,000m. Pretty much higher than any ballon would go I think. Well, then we have a particular space-jumper which was in the vincinity of that height. You should get yourself a GPS simulator. For your

[time-nuts] SSR-6Tr Motorola/u-blox mode not working

I have a couple of SSR-6Tr boards but can't talk to them properly. Here are the things I've tried: @@Am: @@As: Lat 0, Lon 0, Height -0.01 m @@Aw: 1 (UTC) @@Cj: Synergy copyright, version, etc. @@Ga: lat/lon/height I entered earlier @@Ge: TRAIM enabled @@Gf: TRAIM alarm: 500