BG7TBL FA-5-6GP Frequency Counter inside and some tests

[KedasProbe]

Hi,

Some PCB pictures for those that are interested,
PCB board is year 10/2021 and firmware 6/2024
Gate-time maximum is 20sec, above it it waits that long but gives wrong data.
Serial commands in the zip file.


I wrote a program for it since there is no screen on it, if it's not easy to read it's annoying to me anyway, so I decided I can use the one without screen and write a program for it.
It's based on an existing general serial communication program. https://github.com/mcagriaksoy/Serial-Communication-GUI-Program

(Note: I wanted to add some time graphs but I couldn't get it to work, library compatibility....)


EDIT:
- There is no power switch but the PCB board does have a connector for it, if you remove the solder join on the connector pins, at the front left from the led there is some room for a hole.
- I updated excel file so the graphs load faster
 offset is changing with gate-time but also with freq it seems (see offset dip 10Mhz at 1sec and 100Mhz at 0.1sec).
- serial communication is a bit tricky since you have to wait until the measurement is done before it does something and it only remembers the last command given, this can feel like it doesn't work at long gate-times.

[KedasProbe]

Some extra info to reflect on:
Input impedance of CH1 is around 50\$\Omega\$ but for CH2 it's around 32\$\Omega\$

Source code of my program:  https://github.com/Ken26M/FA-5-6GP_MonitorControl
It can store all measurements with a timestamp, the statistics are also added to a csv file when you copy to clipboard.
Even if you use the timelab program to record you can change the settings with this program and then
press disconnect and connect with timelab.

edit:
The program does not use floats (64bit) for the long frequency numbers but decimals.

If you want to use it for an other device like FA-2 or FA-3 you will need to change the parsing code in fa5usbdata.py, function 'add_string' and probably also the line if serial_data[0] == "$" in ui_main.py that decides in which textbox the text line must be displayed.

You may need to install a driver https://ftdichip.com/Drivers/vcp-drivers/ if you see only a USB device and not a com port.

[GigaJoe]

seem same as fa-2 / 3 ; but no display

btw,  the correction  voltage for VECTRON , from tl431 , it connected to input 12v , over regular  resistor, and very sensitive to input  12v voltage
so ideally need very stable 12v input or redesign correction voltage source; or something ext stable Fref
TL431 itself quite   drifty over time.

[KedasProbe]

I did some measurements and it does not seem to be very power supply sensitive.
I only see about -0.3 PPB/V  around 12V
If you change the power supply voltage with 1 volt you have to give it a minute to settle down again (see step response graph)

I also included the warm up time that is long, about -8mHz/hour or -0.8PPB/hour, 1 hour after power on.
You should at least wait 2 minutes before using it but that is normal for an OCXO.

All measurements were done with a gate time of 2sec and a GPSDO 10MHz source signal to measure.

P.S. I didn't add a power switch on the device to avoid adding holes, I added an external switch on the 12V line.

[Kurt_!]

I discovered this program and wanted to try it out (FA-3).
Unfortunately, it won't start. What am I doing wrong? Unfortunately, I'm not familiar with Python programming.
But maybe someone can help me...

[KedasProbe]

Hi,

The program is written to work with FA-5 NOT FA-3, although I don't think it would take much change to make it work for both.
So the freq will most likely not be shown, in worse case the program crashes.
You would need to change the Python code for FA-3 and build again.
I don't have a FA-3 so I can't try it.


I did add an FA-5 .exe for you so you can see what happens without having to setup a Python environment.
Some commands overlap but stay away from command that include an $E sine they will store a change that you may not know how to set back. The others will return to default after power off.
https://github.com/Ken26M/FA-5-6GP_MonitorControl/releases

[Kurt_!]

It's probably more work than I thought.
I've already converted the program to an executable.
...but I haven't done anything other than launch it.
A brief input field appears, and that's it!
It should recognize the COM port?
You can view the data directly with a terminal program.
Shows the frequency in rough...

[tszaboo]

Was anyone able to identify the M25037?
It's likely a PLL IC clone of some ADFxx PLL, but I cannot find anything about it.

[Kurt_!]

Is this from FA-5?

[tszaboo]

Is this from FA-5?

It's on the prescaler board.

[KedasProbe]

It's probably more work than I thought.
I've already converted the program to an executable.
...but I haven't done anything other than launch it.
A brief input field appears, and that's it!
It should recognize the COM port?
You can view the data directly with a terminal program.
Shows the frequency in rough...

I used pycharm to set things up,you don't need to build the EXE to make it work, that is just an extra step to share or move it easily to another PC. the exe can start slow though since it needs to unpack the QT dll library's (GUI) to a temp folder and then it runs it.

What do you see when you start the exe that I put on git?
It should show what you see in the attached picture, when the device is connected the com port should be visible in the list top right. But I do filter out com ports although I think the filter is most likely valid for FA-5 and FA-3
If that works then there is something wrong with your python environment (like wrong versions)

[Kurt_!]

No, that doesn't happen at all.
Just a black input field for 1 second...
Only the "exe" is created. The om folder is.
The latest version is on it.

[KedasProbe]

so when you run this exe it does not start? https://github.com/Ken26M/FA-5-6GP_MonitorControl/releases/download/Test/FA5-counter.exe
You are using windows 10 or 11?  I didn't test Linux

[Kurt_!]

I have a picture of this one of yours.
It's a bit different.

At Connect

[Kurt_!]

My mistake!
It'll get better...

[Kurt_!]

There's a description for commands in FA-2, which should be the same as in FA-3.
But it's not as comprehensive as in FA-5.
You can only do something with the values ​​in the lower left corner.
With math...

[KedasProbe]

It may already work if you change the dollar char $ by FA  (and FB ?)

Code: [Select]

    else:
        if '$' in preprocessed_string:  # continuous data stream
            str_list = preprocessed_string.split(',')
            category = Category.FREQUENCY
            preprocessed_cut_number = str_list[0][2:-3]  # get number but cut off Double error
            measurements.append((category, preprocessed_cut_number))
            if len(str_list) == 3:  # check if power is also present
                category = Category.POWER
                preprocessed_cut_number = str_list[1]
                measurements.append((category, preprocessed_cut_number


[Kurt_!]

I saw something else. The "$A".
Should I change that to "FA" as well?

I'll just test it.....



# keep commands easy to get and change if needed
def make_gate_time_command(gatetime):  # gatetime is string in ms
    gatetimestr = str(int(float(gatetime) * 1000)).zfill(5)
    commandstr = "$A" + gatetimestr + "*"
    return commandstr

[KedasProbe]

That is a send command, these are starting with $ (that stays the same)
I don't know if you can set the gate time with a command, there is a command $G*

[Kurt_!]

Unfortunately, I have to convert everything.
I'm still weak at that.
I tried it once with "Auto_py_to_exe"
But that didn't work?!
I can't find where it was installed anymore either.
And with the commands...

[KedasProbe]

Use pyinstaller to make the exe, the spec file is provided in git. (you give that as parameter)
pyinstaller FA5-counter.spec

[Kurt_!]

Unfortunately, I'm a beginner (Python).
Could it be that I'm missing some modules?

[KedasProbe]

Try to make it work in pycharm first  https://www.jetbrains.com/pycharm/download/?section=windows
then you can worry about making an exe for it.

But you probably need some python courses or AI-assistant to make it work.
Pycharm does make it easy to add missing modules, but you will need to learn how to use it.

[Kurt_!]

Thanks for all the information.
I already knew it wasn't that easy...
The FA-3 already has everything on board.
Large display, plenty of on-board settings.
Software like TimeLap and, to some extent, TestController.
For me, that's very good.

It's just a lot of curiosity...

[Kurt_!]

Steep...

That's called putting obstacles in the way....