Re: [time-nuts] GPS receiver local oscillator

2018-08-15 Thread paul swed
Well thats a heck of a tidbit to learn. I built up hack multipliers and such to get some of the old GPS receivers going. The best was austron 2001. I did retire it as it was really getting to be a pain to operate. You had to know what your doing. Not sure I like that. Neo's have spoiled me. What wa

Re: [time-nuts] GPS receiver local oscillator

2018-08-15 Thread jimlux
On 8/15/18 2:20 PM, paul swed wrote: Wanted to add a bit to the conversation. At least in a number of older GPS receivers circa 1989-1994 the LO was indeed locked to a 10 MHz reference. These were the typical separate mixer and antenna systems. The first LO was 1500 MHz. That is an expensive way

Re: [time-nuts] GPS receiver local oscillator (was: 1PPS for the beginner)

2018-08-15 Thread paul swed
Wanted to add a bit to the conversation. At least in a number of older GPS receivers circa 1989-1994 the LO was indeed locked to a 10 MHz reference. These were the typical separate mixer and antenna systems. The first LO was 1500 MHz. That is an expensive way to go so I can see why whats described

Re: [time-nuts] GPS receiver local oscillator

2018-08-15 Thread Attila Kinali
On Tue, 14 Aug 2018 23:03:46 -0400 Charles Steinmetz wrote: > > If you want a product that ships on time, you dont buy Maxim ;-) > > While I agree with the sentiment, I imagine that time nuts who are > looking for solutions on-list are mostly hobbyists, not industrial > designers (who would al

Re: [time-nuts] 1PPS for the beginner

2018-08-15 Thread Björn
> On 15 Aug 2018, at 14:46, Poul-Henning Kamp wrote: > > > In message > , Peter > Vince writes: > >> I was astonished to see the pulse-width in the document defined from the >> base of the (sharp-cornered!) edges, and not the mid-point - totally >> impractical! > > Given that the ou

Re: [time-nuts] 1PPS for the beginner

2018-08-15 Thread Jim Harman
On Wed, Aug 15, 2018 at 8:40 AM Dana Whitlow wrote: > On Peter Vince's topic, *does anybody in the group know what part of the* > *waveforms transmitted by WWV & WWVB mark the second boundaries?* > > For WWV and WWVH, the second marker is the beginning of the first cycle of the tick waveform. See

Re: [time-nuts] 1PPS for the beginner

2018-08-15 Thread Poul-Henning Kamp
In message , Peter Vince writes: >I was astonished to see the pulse-width in the document defined from the >base of the (sharp-cornered!) edges, and not the mid-point - totally >impractical! Given that the output is not specified into a defined impedance, termination or even cable-leng

Re: [time-nuts] 1PPS for the beginner

2018-08-15 Thread Dana Whitlow
On Peter Vince's topic, *does anybody in the group know what part of the* *waveforms transmitted by WWV & WWVB mark the second boundaries?* I was once comparing the timing of PPS pulses from a GPS receiver with WWV's ticks, and saw about 5 msec delay to the ticks (in south central Texas). Obviousl

Re: [time-nuts] 1PPS for the beginner

2018-08-15 Thread Peter Vince
I was astonished to see the pulse-width in the document defined from the base of the (sharp-cornered!) edges, and not the mid-point - totally impractical! Near the top of the previous page it says: "If required for testing purposes, the pulse width at the 50% level may be determined by extrapolati