Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Hi fellow time-nuts, sorry for keeping quiet after having dropped my question. I was busy travelling an since yesterday our booth at the IMS2016/MTT keeps me busy too. I will answer to the various comments as soon as I got some more quiet minutes. I look forward to see many time-nuts this

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

From: Wes A cleaver design, but the OP wanted 1pps. I have the Leo Bodnar GPSDO. It too is a nice frequency standard, but it doesn't know what time it is. = This box can do either 10 MHz or 1 PPS. http://leontp.com/ "Coming soon" Cheers, David --

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

However the value of the second time constant in the active PI filter required to achieve reasonable damping will be around 1600 seconds. This corresponds to an active PI filter proportional gain of 16. Bruce On Wednesday, 25 May 2016 3:20 PM, Bruce Griffiths

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

When comparing a 10MHz OCXO divided down to 1Hz with a GPS PPS signal, the effective VCO gain (Ko/N) is likely to be around 6E-7 rad/s/V (eg HP10811A) and the phase detector gain around 1V/rad. Consequently a PLL loop bandwidth of 100uHz only requires an Integrator time constant of around  100

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

A cleaver design, but the OP wanted 1pps. I have the Leo Bodnar GPSDO. It too is a nice frequency standard, but it doesn't know what time it is. On 5/24/2016 9:53 AM, Graham / KE9H wrote: If you want an "existence proof" for a simple, mostly analog, a few digital counters, no software or

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

If you want an "existence proof" for a simple, mostly analog, a few digital counters, no software or microprocessor GPSDO, look at the "Miller" GPSDO. He designed it for his own use, then put it into production because of demand for a simple, cheap GPSDO. It has been characterized, and works well

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Hi Ok, so how would you do a pure analog GPSDO? The GPS receiver and that side of it are what they are. I’ll assume that you have a 1 pps out of a module. Your OCXO needs to get to 1 Hz via dividers. You can do that with digital dividers or with a chain of regenerative dividers. One is a

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

> >> If that sounds too weird, I am open to receive advises for a microcontroller >> based solution. > > If you want to go that way, probably the simplest solution would be to > take one of Nick Sayers boards, pull out the GPS receiver and feed the > PPS input from your GPS receiver. It’d be

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Hi Is a DAC in our out? I can (with some effort) build the entire computing engine needed for a GPSDO out of 7400 series logic. It’s actually easier than you might think. Since that’s “small scale logic” is it in bounds? To me at least, analog is just that, no gates, no 1’s no 0’s, just a

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

The grid current of most tubes (apart from electrometer tubes operated at low voltage) is much larger than most FETs (apart from very large area ones).. The other issue with tube grid currents is that zero current corresponds to a delicate balance between electon and ion currents so the grid

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

On Sun, 22 May 2016 15:52:16 -0700, you wrote: >... > >The DAC is nothing more than 16 precision resisters each >one twice the value of the next one, each connected to one bit of the >register by a transistor switch. It will take beyond a heroic effort to get 16 bits of differential

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

measurement' Subject: [time-nuts] Simple solution for disciplining OCXO with 1 PPS Hello Fellow time-nuts, I am looking for a simple solution to discipline my 10 MHz reference OCXO in my private lab with an 1 PPS signal from a separate GPS receiver. I am curious if there is a solution possible without

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

I like the little boards at: http://navspark.mybigcommerce.com/development-boards/ It's a GPS with a fully programmable 32-bit Arduino-compatible processor. $22 Crowdsourced about 3 yr ago, matured now. Various versions; you can even have Beidou :-). Don On 2016-05-22 19:45, Tom Van Baak

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

> Can a pure analog design access the sawtooth correction? My GPS > receivers send sawtooth as a digital message on a serial port. I > don't know if saw tooth correction is required to meet his spec. Hi Chris, Many GPS/1PPS receivers don't output sawtooth information and yet they work really

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Hi No, there is no purely analog way to access the sawtooth information. If you restrict yourself to “pure analog” then the PPS will be bopping around by +/- 10 to +/-20 ns each second. Put another way, you start out with 1 to 2x10^-8 at 1 second. The same thing is true at 10 KHz or at any

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

bneu...@t-online.de said: > Hello Fellow time-nuts, I am looking for a simple solution to discipline my > 10 MHz reference OCXO in my private lab with an 1 PPS signal from a separate > GPS receiver. I am curious if there is a solution possible without > programming a microcontroller, as I am an

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

If you can build with small scale TTL gates you can save the need for a huge precision capacitor by storing the current EFC value in a 16-bit register/counter. This 16-bit register drives a DAC. Then you build a phase detector that can detect if the XO leads or lags the GPS. If it leads you

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

On Sun, 22 May 2016 19:41:25 +0200, Bernd Neubig wrote: > Hello Fellow time-nuts, > I am looking for a simple solution to discipline my 10 MHz reference > OCXO in my private lab with an 1 PPS signal from a separate GPS > receiver. There seems to be some TU60 D102 on *bay search for #:

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

On Sun, May 22, 2016 at 3:52 PM, Attila Kinali wrote: > Judging from the ADEV plots of the M12 receiver from TvB[1], which hit > 10^-10 (w/ sawtooth) around 200s, I'd say that 10^-10 @1000s should be > easy. Can a pure analog design access the sawtooth correction? My GPS

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

How do you measure "simple"? Do you count the chips and the passive components or do you count lines of code? Or maybe you draw a block diagram and count the blocks and the number of interconnections? If you count chips the design with the micro controller wins by a long shot But if you count

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

On Sun, 22 May 2016 19:41:25 +0200, Bernd Neubig wrote: > Hello Fellow time-nuts, > I am looking for a simple solution to discipline my 10 MHz reference > OCXO in my private lab with an 1 PPS signal from a separate GPS > receiver. > I am curious if there is a solution possible without programming

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Hoi Bernd, Is there any special reason for this endavour or are you just courious what can be done? On Sun, 22 May 2016 19:41:25 +0200 "Bernd Neubig" wrote: > I am well aware, that such a solution would have a lot of disadvantages, > as it cannot effectively compensate

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Bernd, On 05/22/2016 07:41 PM, Bernd Neubig wrote: Hello Fellow time-nuts, I am looking for a simple solution to discipline my 10 MHz reference OCXO in my private lab with an 1 PPS signal from a separate GPS receiver. I am curious if there is a solution possible without programming a

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Hi Of course it’s possible, you simply need enough high quality film capacitors to make up the control loop integrator. You probably also would use a pile of the same capacitors to slow down the PPS jitter a bit before it went into the loop. The setup process would probably involve a bunch of

Re: [time-nuts] Simple solution for disciplining OCXO with 1 PPS

Among Simple , analog, 1PPS you'll have to pick two of the three. The miller GPSDO needs 10KHz it's simple and analog. http://www.jrmiller.demon.co.uk/projects/ministd/frqstd0.htm The IK0OTG is simple, uses 1PPS and is digital

[time-nuts] Simple solution for disciplining OCXO with 1 PPS

Hello Fellow time-nuts, I am looking for a simple solution to discipline my 10 MHz reference OCXO in my private lab with an 1 PPS signal from a separate GPS receiver. I am curious if there is a solution possible without programming a microcontroller, as I am an old-fashioned "analogue" guy ;) I