Re: [time-nuts] trimble Thunderbolt, how to get 25 or 27 mHz from it??

On Jan 19, 2018 6:01 AM, "John Ackermann N8UR" wrote: > Sorry to hijack the thread, but the Si5351 looks interesting for another > project I'm working on. I know it specifies "low jitter" but has anyone > looked at the phase noise? Is it usable for RF applications? > Datasheet

Re: [time-nuts] trimble Thunderbolt, how to get 25 or 27 mHz from it??

Sorry to hijack the thread, but the Si5351 looks interesting for another project I'm working on. I know it specifies "low jitter" but has anyone looked at the phase noise? Is it usable for RF applications? Thanks, John On 01/18/2018 08:53 AM, D. Jeff Dionne wrote: Chris, You don't

Re: [time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

Hi It is very much a 12V antenna. It also is a “50 db gain” antenna as well. Most of the timing gear is looking for 20 to 30 db less gain than that in an antenna. The good news is that you can run a really big splitter after one to drive lots of stuff. The bad news is that you may still need

Re: [time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

On Thu, Jan 18, 2018 at 1:39 PM, John Green wrote: > I have been gone for a good while, but now that I am officially retired, I > thought I would get back into the time/frequency hobby. I recently bought a > Trimble 33429-00 antenna off eBay. I can't seem to find much on the >

Re: [time-nuts] MTI-Milliren OCXO Issue

Hi They always had a pretty lean operation and some unique approaches as part of their business plan. That said, they do seem to be a going concern. Bob > On Jan 19, 2018, at 3:54 AM, John C. Westmoreland, P.E. > wrote: > > Hello All, > > Just wondering -

Re: [time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

Hi Since this *is* an L1 / L2 antenna, there are a lot of things you might be doing with it. If indeed dual frequency GPS is part of the intended use, the survey oriented gear will be slightly happier if the “right” corner faces north. It only really counts in that sort of L1 / L2 data

[time-nuts] minimalist sine to square

John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line receiver [2]. That would be an ideal single-chip

[time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

If that Leica antenna is the same one as the antennas that were sold on Ebay a few years back, they run just fine on 5V. I have used them on Thunderbolts quite a bit. > I decided that the Leica choke ring antenna I got a while back took 12 volts because the power

[time-nuts] "Confessions of a Reformed Frequency Standard Nut"

https://hackaday.com/2018/01/17/confessions-of-a-reformed-frequency-standard-nut/ "Or are you chasing that last digit just because it’s there?" ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

Re: [time-nuts] minimalist sine to square

Tom, I recently built such a device using a couple of stages of a 74HC04, with the RF input to the 1st stage AC coupled and the input biased by a high-value (a couple of megohms) resistor feeding back from the output of the first inverter stage to the input of that stage. It's so dirt simple,

Re: [time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

Hi The antenna has a measured / documented pattern (amplitude and more importantly phase). If you have it pointed in a known direction, that information can be used when post processing carrier phase information. If you are trying to get to mm / picosecond levels on an multi hour L1/L2

Re: [time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

> What's in the antenna that makes North interesting? and/or how would a > receiver take advantage of it? Hal, The people that work at the mm level get very picky about details; antenna reception is not perfectly symmetrical or centered or equal at every frequency or angle. There is a

Re: [time-nuts] minimalist sine to square

SN65LVDS34D --- Graham / KE9H == On Fri, Jan 19, 2018 at 3:45 PM, Vlad wrote: > > > On 2018-01-19 14:31, Tom Van Baak wrote: > >> John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It >> performs very well but requires +10 V. >> > > > I am using Wenzel approach

Re: [time-nuts] minimalist sine to square

On 1/19/18 11:31 AM, Tom Van Baak wrote: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line

Re: [time-nuts] minimalist sine to square

Tom What's the input signal amplitude? What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? Bruce > On 20 January 2018 at 08:31 Tom Van Baak wrote: > > > John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs > very well but requires +10 V. >

Re: [time-nuts] minimalist sine to square

On 1/19/18 11:31 AM, Tom Van Baak wrote: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line

[time-nuts] TADD-1 question

I have a sig gen that uses a single BNC for input/output of the 10 MHz reference. You have to set it for in or out using the interface. However, if the sig gen thinks that the external reference is no longer there, it automatically switches to using the internal reference, and outputing it on the

Re: [time-nuts] minimalist sine to square

In message <898171c2-0e9a-6a2a-dcfc-b7d893f89...@earthlink.net>, jimlux writes: >What about the plethora of LVDS receivers - they're basically a >differential input thresholder, with deliberate hysteresis, looking for >a 300 mV shift across a 100 ohm resistor. I played with that, I

Re: [time-nuts] minimalist sine to square

In message <63ae173b-93f4-ffe4-ddf1-655761665...@earthlink.net>, jimlux writes: >On 1/19/18 11:31 AM, Tom Van Baak wrote: >You do want to watch the common mode voltages - some of the parts are >not good about having the signals swing near the rails (or beyond). Also be aware that specs

Re: [time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

kb...@n1k.org said: > If indeed dual frequency GPS is part of the intended use, the survey > oriented gear will be slightly happier if the “right” corner faces north. What's in the antenna that makes North interesting? and/or how would a receiver take advantage of it? -- These are my

Re: [time-nuts] minimalist sine to square

On 1/19/18 12:54 PM, Poul-Henning Kamp wrote: In message <898171c2-0e9a-6a2a-dcfc-b7d893f89...@earthlink.net>, jimlux writes: What about the plethora of LVDS receivers - they're basically a differential input thresholder, with deliberate hysteresis, looking for a 300 mV shift across a

Re: [time-nuts] minimalist sine to square

On 2018-01-19 14:31, Tom Van Baak wrote: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I am using Wenzel approach without modification to drive it from +5V. I didn't see any issues for my applications (usually it perform

Re: [time-nuts] minimalist sine to square

> Tom > What's the input signal amplitude? > What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? > Bruce It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, 1 Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. It doesn't have to have stunning

Re: [time-nuts] minimalist sine to square

A fast DIP comparator such as an LT1016 should work but it won't perform well without an effective ground plane. If a CMOS gate is used then a low Q LC impedance step up network or equivalent will be needed to increase the signal swing at the gate input. Add a couple of schottky diode clamps

[time-nuts] minimalist sine to square

The Efratom/Tektronix PTB-100 took the 10Mhz sine out of the FRK brick, AC coupled it to the input of an 74LS14 biased with a votage divider from +5 to ground. 4 parts! Cheers, Corby ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe,

Re: [time-nuts] minimalist sine to square

Now, if one added an optional TTL threshold 5V CMOS single gate inverter/buffer to produce 5V output when required and added an SMT 5V->3.3V regulator and mounted it all on a small PCB with pins to make it DIP compatible that would meet the brief and then some. Otherwise an SMT (not many DIP

Re: [time-nuts] minimalist sine to square

Something like the attached circuit is suitable for driving the MCU clock input directly. The diodes should be schottky signal diodes like the 1N5711 series. The series resistors limit the diode peak current and the CLK input protection network current. It should work with inputs from 1V pp to

Re: [time-nuts] minimalist sine to square

Bob With a 1V p-p sort of output, a simple matching network will get you into the 4 to 6V p-p range. Drive that into a 5V compatible CMOS gate and move on …. If you have a super hot output, put a 3 db pad on it. Bob > On Jan 19, 2018, at 5:40 PM, Tom Van Baak wrote: >

Re: [time-nuts] "Confessions of a Reformed Frequency Standard Nut"

And if I do some longer term averaging, I can get another one after that. :-) --- Graham == On Fri, Jan 19, 2018 at 11:16 AM, Ron Bean wrote: > https://hackaday.com/2018/01/17/confessions-of-a-reformed- > frequency-standard-nut/ > > "Or are you chasing that last

Re: [time-nuts] minimalist sine to square

Am 19.01.2018 um 20:31 schrieb Tom Van Baak: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line

Re: [time-nuts] TADD-1 question

Hi Joe, On 01/19/2018 09:52 PM, Joseph Gray wrote: > I have a sig gen that uses a single BNC for input/output of the 10 MHz > reference. You have to set it for in or out using the interface. However, > if the sig gen thinks that the external reference is no longer there, it > automatically

Re: [time-nuts] Time interval measurement vs dual mixer

Hi, Thanks for all answers. I'm trying to estimate the uncertainty of GPS Common View data (which is based on TIE measurement) and compare it to data from dual mixer method. Message: 6 Date: Wed, 17 Jan 2018 11:08:45 -0500 From: Bob kb8tq To: Luciano Paramithiotti

[time-nuts] Looking for information regarding Trimble 33429-00 microcentered GPS antenna.

I have been gone for a good while, but now that I am officially retired, I thought I would get back into the time/frequency hobby. I recently bought a Trimble 33429-00 antenna off eBay. I can't seem to find much on the internet about it. Google has not been my friend. First, I assume the "micro

Re: [time-nuts] trimble Thunderbolt, how to get 25 or 27 mHz from it??

Chris, You don't need to do that. The SiLabs part will accept the 10MHz sin from an OCXO directly into the XA pin. That pin normally connects to a crystal, so there is a high gain amp in the chip to square it up already... I did the tests a while back, see the thread here:

[time-nuts] MTI-Milliren OCXO Issue

Hello All, Just wondering - has anyone made any recent purchases with MTI-Milliren regarding OCXO's? I've had a recent interaction with them that makes me think their OCXO's could go the way of the dinosaur; maybe it's just me; hoping someone on the list has some recent experience with

Re: [time-nuts] minimalist sine to square

Even the modern PICs spec 50mA max input currents. Simulation indicates 20mA peak diode currents without the 330 ohm resistors for a 2V pp input, even more for higher input signal levels. If one can guarantee that input is around 1V pp then the extra diodes and resistors aren't required. If its

Re: [time-nuts] minimalist sine to square

Yes, I was just trying to see how far the circuit could be pushed (+27dBm input was still OK). With +13dBm input peak diode current without 100R and 330R resistors is about 20mA for the 3.3V circuit with an impedance step up from 50 to 400 ohm. My 100MHz Wenzel OCXO has an output of around

[time-nuts] minimalist sine to square

Tom, Hook the 53132A calibrator that I sent you and check one of the calibrator outputs for signal goodness. It uses the sine-square circuit in the LPRO-101 manual (input cap connected to center of a 39K/39K voltage divider connected to a 74HC gate (74AC gates have some advantages and

Re: [time-nuts] minimalist sine to square

Hi My main point is that a +22 dbm (or even 16 dbm) OCXO is a *very* rare item. If your signal generator is set to +22 dbm … shame on you. If the part can do well over +7 to +13 dbm, that will cover the vast majority of the 10 MHz oscillators / signal sources out there. Bob > On Jan 19,

Re: [time-nuts] minimalist sine to square

Hi Unless you really beat on the thing for days on end, you can do without the 330 ohm and 100 ohm resistors (along with the two diodes). Most modern gates have pretty robust protection diodes. The source impedance is high enough after the transform that the available current is pretty low. On

Re: [time-nuts] minimalist sine to square

That network was for a 10MHz input. For 5MHz double the L and C values. For 3.3V one could use a lower step up say from 50 to 400 ohms rather than from 50 to 800 ohms. 1uH and 150pF and change 1k6 resistors to 820R. Swap the 5V supply for a 3.3V supply. L and C values aren't critical 5% or