New product: tinyGTC, GNSS disciplined oscillator and universal 2 input Timer an

[UnijunctionTransistor]

A lot of functionality at a very affordable price.
Don’t need one right now, but have bookmarked the website for a future purchase.

Thanks.

Related question, do you ship to the US?

[erikka]

R&L will have stock soon

[ulix]

Hi Erik,

great to see another product developed by you! I'm very interested, but I would like to know the following:

Can the tinyGTC be used to measure the time difference between two signals (less than 20MHz in repetition rate, but fast rising, nanosecond width) — for example, between the REF output and one of the inputs (A/B) — with a resolution in the tens of picoseconds? Additionally, is it possible to display this as a histogram (counts vs. ΔT)?

Your dedication is an absolute inspiration.
cheers

[erikka]

This is a 16 ns wide pulse with a 5 MHz repetition rate coming from an external source linked to a reference clock send into the A input.
The tinyGTC is using the same reference clock as REF input and it timestamps every 10 ms at up edge and the timestamp is wrapped at 100 ns to get the "time versus the REF"
The measured time is displayed in a histogram with 80 buckets each 3 ps wide over the last 21874 measurements (maximum measurements that can be accumulated into a histogram)
You can see the quantization of the time in the histogram

[erikka]

The screen capture was missing.

[erikka]

This one is a bit more challenging.
Two 1 MHz, 24 ns wide pulses with fixed time between the two pulses, send in to inputs A and B.
Measurement is set to measure the time difference between A and B
This is more difficult because you get twice the measurement noise due to two inputs being used.

[erikka]

New video showing frequency, phase and time stamping measurement and various ways to show the results of these measurements.

[bingo600]

Dammm ....

30 days lead time on Eleshop   
I was on the looks for an early xmas present

[erikka]

New video, how to setup the tinyGTC in combination with TimeLab
https://youtu.be/R9YNsT9EPF4

[KedasProbe]

I updated the firmware to version 1.0-12 and did some basic tests.

two remarks
1) is there a reason you start with \r   (I use readline() )
\r10000000.0000068303198 CHA\n

Maybe you have the sequence reversed and you end with  \n\r instead of  \r\n ?

2) The calculation of STDEV is too low are you using an other calculation? I verified with USB log data.
(see screenshot, 30.4µHz is correct)

Data of the TinyGTC looks better than the GB7TBL FA-5 (measuring its own reference)
Clearly no gap since I get 1000ms interval, with FA-5 I get unstable something like 1023ms

[DaneLaw]

Dammm ....

30 days lead time on Eleshop   
I was on the looks for an early xmas present

You can get it from China if it's so important to get it before Christmas.
Zeenko/Hugen is the OEM that Erik is using, so it's the same backland that European sources like Eleshop are sourcing from.

Their official store.
https://aliexpress.com/item/1005010361182255.html?

The biggest issue is that you seem to be based in Denmark, and the Aliexpress system seems kind of messed up lately, as 80% of my wishlist was suddenly overnight greyed out with a blank white slide "not available to your region"/Denmark.

Seems to be centered around Denmark for some strange reason, as if I change my region to other EU countries, incl. neighboring countries, most of these items are again purchasable.

The TinyGTC was, in fact, purchasable from Denmark just a few days ago from Zeenko's Aliexpress store, but now its "region verboten" and locked away behind a white regional slide, while it's still purchasable from these other EU countries like Germany, Spain, France etc.  https://imgur.com/a/ro7I4yw

Not sure why Aliexpress lately has gone so ballistic in censoring "listings" away from Danish consumers, quite annoying. Labgear, mobilephones, DJI drones & many other science & tech segments just gone if you have a Danish address... instead it's primarily low-cost Temu/Wish-like chinese garbage that is left.

One can always use parcel forwarding and rely on a flip address in all these other EU countries, and simply bounce a parcel through there, but it adds time, alongside significant expenses.
And in regard to TinyGTC, there is close to no financial gain getting it directly from China, as the 407/412 prices look to be around the same as EU vendors (at least for the moment) the primary benefit would be time-related from lack of EU stock, and get it before Christmas.

[aeg]

Time resolution is 40 ps.

The measured time is displayed in a histogram with 80 buckets each 3 ps wide over the last 21874 measurements

So is the resolution 40ps or 3ps? 3ps is really impressive!

[KE5FX]

New video, how to setup the tinyGTC in combination with TimeLab
https://youtu.be/R9YNsT9EPF4

Hey, Erik -- can you send an ASCII text dump to john (at) miles.io with some frequency readings that demonstrate the erroneous phase slope that you observed in the video?   This isn't something I've run into before, so I'd like to make sure there's nothing unexpected going on.  I don't usually import frequency data myself, so maybe there's some room for improvement that I've overlooked.

[erikka]

John,
Will do
When I change the settings to eliminate the linear regression the phase derived from the frequency does not show this drift so I think this is an artefact from the linear regression or this is due to some rounding somewhere in the tinyGTC

[erikka]

So is the resolution 40ps or 3ps? 3ps is really impressive!

The Time resolution (single event) is 40 ps
The time data is derived from partial higher resolution data so I use 10 ps internal calculation resolution
The 3 ps mentioned was the bucket size in the specific histogram and as the time is rounded to 10 ps only one in every 3 buckets was used.

[smk]

two remarks
1) is there a reason you start with \r   (I use readline() )
\r10000000.0000068303198 CHA\n

Maybe you have the sequence reversed and you end with  \n\r instead of  \r\n ?

Each line ends with \n\r. At one line per second it is easy to see that the \r is sent right after the \n.

2) The calculation of STDEV is too low are you using an other calculation? I verified with USB log data.
(see screenshot, 30.4µHz is correct)

I can see that too. The factor between the two is a bit smaller here but almost constant 1.2 to 1.24 tested at some frequencies between 10kHz and 100MHz

[erikka]

Each line ends with \n\r. At one line per second it is easy to see that the \r is sent right after the \n.

 The factor between the two is a bit smaller here but almost constant 1.2 to 1.24 tested at some frequencies between 10kHz and 100MHz

The line ending will be corrected in the next release.
And I will check the STDEV calculation

[smk]

This is a fascinating instrument. I used it too check the outputs of a LBE-1421 2-port GPSDO locked clock source set to 1.23456789Hz and 1.23456789GHz simultaneously.
I used these frequencies because they are close to the lower and upper end of the range of the LBE-1421 and it is easy to count the digits.
Both GPS antennas were indoors.

[xtech]

It looks many people (including me) who ordered ZC412 from official Zeenko Store on aliexpress finally gets ZC407. Discussion with Zeenko is tough so watch out. Finally he blamed me this was my fault (!!!) but actually there was multivariant offer which was later changed and it looks they did not managed it properly.

Anyway, is it possible to convert ZC407 to ZC412? There is ADF4107 on the A input which acts as a prescaler. What chip is used in the 12GHz version and what about other updates (SW) to get 12GHz?

[erikka]

See this message from hugen regarding receiving a ZC407 after ordering a ZC412
https://groups.io/g/tinygtc/message/1623

[xtech]

Actually that thread triggered me to write here as discussion with Zeenko customer support lead to nowhere. It looks they even trying to block possibility of item return on aliexpress (I was asked to provide official parcel weight confirmation from post office). Zeenko customer support only offer was 15$ coupon (not even refund) to buy another ZC412. Really?!

Anyway meter you have designed is really nice. Please consider providing details on converting it to 12GHz.

[erikka]

To all that received a 407 after ordering a 412
You will be contacted by zeenko..
PM me next week if that did not happen

[KedasProbe]

I confirm that in version 1.0-16 USB- log line ending and STDEV are fixed.

(if only big companies fix bugs so fast )

[smk]

The line ending will be corrected in the next release.
And I will check the STDEV calculation

Thanks for these correcetions and the other improvements in V1.016.
I think I ran in two other issues, one of them again concerning line endings. When sending SCPI commands the answer ist terminated with CR CR LF in a lot of cases and CR LF in some others.
The other issue is more serious. With the GHz prescaler activated my ZC407 shows wrong Count and Total Count values. The displayed values are off by a factor of 100/24.

[erikka]

The other issue is more serious. With the GHz prescaler activated my ZC407 shows wrong Count and Total Count values. The displayed values are off by a factor of 100/24.

Will be solved in release due next week