[time-nuts] Least costly 10 MHz reference solution
Greetings, I have been reading what I can find on Rubidium and GPSDO approaches, but there are some fine points that do not make it clear which is the best 'bang for the buck' solution. My requirement/desire is to have a 10 MHz standard for my lab that I can trust to an accuracy of 7 decimal places (10 ppb?), so anything that is good to a few ppb is certainly adequate for what I am looking for. I have a OCXO unit that is voltage adjustable - for example, adjusting this to 10.000 MHz per my HP 5334A requires -12.71V. So the simple (maybe) question is, should I go for a Rubidium disciplined unit, or go with a home-brew GPSDO solution using the Vectron OCXO I already have? My main cause of confusion is ignorance concerning all the GPS solutions out there with 1pps outputs, to use in a GPSDO, and which ones jitter too much to be useful (solutions under $50 exist). Thanks in advance. Russ K0WFS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Least costly 10 MHz reference solution
Russ, Welcome! On 01/23/2013 05:48 PM, Russ Ramirez wrote: Greetings, I have been reading what I can find on Rubidium and GPSDO approaches, but there are some fine points that do not make it clear which is the best 'bang for the buck' solution. My requirement/desire is to have a 10 MHz standard for my lab that I can trust to an accuracy of 7 decimal places (10 ppb?), so anything that is good to a few ppb is certainly adequate for what I am looking for. I have a OCXO unit that is voltage adjustable - for example, adjusting this to 10.000 MHz per my HP 5334A requires -12.71V. So the simple (maybe) question is, should I go for a Rubidium disciplined unit, or go with a home-brew GPSDO solution using the Vectron OCXO I already have? My main cause of confusion is ignorance concerning all the GPS solutions out there with 1pps outputs, to use in a GPSDO, and which ones jitter too much to be useful (solutions under $50 exist). Thanks in advance. A rubidium or GPSDO such as Thunderbolt can be found fairly cheaply. If you go for a Thunderbolt, get one with antenna as a kit, mostly because it is a handy way to get started. For better stability you can get a better antenna later, if the need would occur. The rubidium should give you the precision you need straight out of the box, unless it has issues. In order to control if it has issues, having the ability to at least compare to GPS becomes obvious, so you end up wanting that GPSDO anyway. You can get both for reachable money anyway, if you look around long enough. Doing a home-cooked GPSDO is fun naturally, and there is an art in low-budget designs giving fair amount of performance. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Least costly 10 MHz reference solution
No question, You want a GPSDO. Yes you can buy a Rb or a high-end OCXO but neither of these is connected to any kind of standard and will need to be calibrated to be of use. The GPS serves as a standard and you need that before the other options. The next question is which GPSDO? For most people that would be a Thunderbolt but the prices are going up on those. Then you will need a good antenna installation. On Wed, Jan 23, 2013 at 8:48 AM, Russ Ramirez russ.rami...@gmail.com wrote: Greetings, I have been reading what I can find on Rubidium and GPSDO approaches, but there are some fine points that do not make it clear which is the best 'bang for the buck' solution. My requirement/desire is to have a 10 MHz standard for my lab that I can trust to an accuracy of 7 decimal places (10 ppb?), so anything that is good to a few ppb is certainly adequate for what I am looking for. I have a OCXO unit that is voltage adjustable - for example, adjusting this to 10.000 MHz per my HP 5334A requires -12.71V. So the simple (maybe) question is, should I go for a Rubidium disciplined unit, or go with a home-brew GPSDO solution using the Vectron OCXO I already have? My main cause of confusion is ignorance concerning all the GPS solutions out there with 1pps outputs, to use in a GPSDO, and which ones jitter too much to be useful (solutions under $50 exist). Thanks in advance. Russ K0WFS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Least costly 10 MHz reference solution
Hi Not to pick nits, but 7 decimal places at what input frequency? Seven places is 10 ppb at 10 MHz. If the input was 100 MHz, it would be 1 ppb. The distinction is significant, since it crosses a boundary. At 10 ppb a free running Rb is fine with no adjustments. At 1 ppb, some adjustment might be needed. You might also want a standard that's 5X better than the expected result. That would get you into the 2 to 0.2 ppb range. Lots of fiddly little details... Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Russ Ramirez Sent: Wednesday, January 23, 2013 11:48 AM To: time-nuts@febo.com Subject: [time-nuts] Least costly 10 MHz reference solution Greetings, I have been reading what I can find on Rubidium and GPSDO approaches, but there are some fine points that do not make it clear which is the best 'bang for the buck' solution. My requirement/desire is to have a 10 MHz standard for my lab that I can trust to an accuracy of 7 decimal places (10 ppb?), so anything that is good to a few ppb is certainly adequate for what I am looking for. I have a OCXO unit that is voltage adjustable - for example, adjusting this to 10.000 MHz per my HP 5334A requires -12.71V. So the simple (maybe) question is, should I go for a Rubidium disciplined unit, or go with a home-brew GPSDO solution using the Vectron OCXO I already have? My main cause of confusion is ignorance concerning all the GPS solutions out there with 1pps outputs, to use in a GPSDO, and which ones jitter too much to be useful (solutions under $50 exist). Thanks in advance. Russ K0WFS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
