10MHz GPSDO by "BH3SAP"

[Kurt_!]

Ft232 Usb Uart (com7) Did not find any match for FA001....

Das zeigt Testcontroller an....

Habe die Baudrate auf 115200 und wieder auf 9600 gestellt

[KungFuJosh]

Don't try TestController yet. You need to know if you can get a *IDN? response. The easiest way would be connecting to COM7 in Putty or something like that.

If you want to use TestController, it either needs a driver definition file, or you need to select scan serial ports and see if it shows anything.

[Kurt_!]

I have a terminal program connected.
It spits out different numbers in FA000...

Ps.:

But only if I have the GPSDO connected...

[KungFuJosh]

I have a terminal program connected.
It spits out different numbers in FA000...

Can you copy and paste the exact response it gives to *IDN? ?

[Kurt_!]

I entered and sent....

117<\r><\n> FA0009999999.999600000<\r><\n> FA0009999999.999300000<\r><\n> FA0010000000.000100000<\r><\n> FA0009999999.999500000<\r><\n> FA0009999999.999500000<\r><\n> FA0009999999.999901960<\r><\n> FA0009999999.999901960<\r><\n> FA0010000000.000000000<\r><\n> FA0009999999.999800000<\r><\n> FA0009999999.999600000<\r><\n> FA0010000000.000500000<\r><\n> FA0010000000.000000000<\r><\n> FA00....

and so forth

It does not respond to commands

[KungFuJosh]

Is that with a 10MHz signal applied? It looks like the current frequency listing activity.

[Kurt_!]

Yes, I think so too. It only happens when the GPSdo is connected.
They probably have a program for it. But where do I get it from?

Ps.:

I'll keep looking. The FA-2 is almost the same.

[KungFuJosh]

It seems like you could use it with anything that can receive the serial data. Maybe even Excel, but I dunno. Worst case: log it in a terminal, copy and paste into Excel, and then chart it.

[Kurt_!]

I just found Timelab.....

It'll take a little while.
See you tomorrow.
Good night.

[Kurt_!]

I don't think the Timelab is suitable.
Can you show me a diagram with the test controller and the small Dpsdo?
I also found the Lady Header, let's take a look...
Looking at your equipment, it's not bad!

[KungFuJosh]

I don't think the Timelab is suitable.
Can you show me a diagram with the test controller and the small Dpsdo?
I also found the Lady Header, let's take a look...

You want me to run a test with the GPSDO on TestController? I'll set it up and run it soon.

Looking at your equipment, it's not bad!

[Kurt_!]

The FA-3 can do a bit too.
P-P, FIN, AVG, MAX, MIN...but not graphics yet.
I thought you already had it ready.
Because you mentioned a short fidgeting.
How big should it be? You want the comparison, right?

[KungFuJosh]

5 or 10 minutes when the stuff is well warmed up should be enough. You can do longer if you want.

I had to do the test over because I dunno if/where I saved the old screenshot.

1 sec log time in TC, 1 second gate time on 53132A using the same GPSDO as an ext ref attached. I think it's a pretty good representation of what I expect. Note that the GPSDO being tested has a replacement ISOTEMP OCXO (age unknown) and I've had this GPSDO running constantly for about 6 days after the mods.

Thanks,
Josh

[Kurt_!]

Great. Too bad it doesn't work for me with the test controller.
But I got TimeLab running. Now I have to test it.
It evaluates the Fa... numbers.
Maybe the program will work for you too?

[KungFuJosh]

Which program doesn't matter. You can get  log data and see what the AVG, PP, and SD values are.

[ME]

can i connect this bh3sap to my pc using a max 232 ic?

[Kurt_!]

Which program doesn't matter. You can get  log data and see what the AVG, PP, and SD values are.

A few questions for my very knowledgeable counterpart!?
Have you made any changes to the settings on the "small" GPS? Other than replacing the oscillator.
I think you can be satisfied with the values.
(Diagrams).
I'm testing Timelab. You can do a lot with the program. I've already saved a few diagrams...
There's still a lot to write!?

[KungFuJosh]

I have fredo_'s firmware v0.1.16. The settings adjustments made were to match the OCXO version, GPS module type, time zone, and baud rate of 38400.

[Kurt_!]

I have to change something there too.
I have everything set to standard.
It often adjusts according to the small one...
and so the frequency always goes up and down a bit (a few millihertz)...
Which isn't apparent on the big one, and on yours, either.

Der Kleine Ist mit int OSC..

Ps.:
Do you have one antenna or two?

https://www.eevblog.com/forum/Themes/default/scripts/advanced_uploader/images/uploader_icon.png

[KungFuJosh]

One antenna. I got PP 3mHz using the SDG2122X with 1s gate/1s sampling. I'd expect better from the GPSDO directly.

[Kurt_!]

FA-3 cannot be trimmed more precisely. (Internal OSC)

Ps.:
The big one doesn't have that!

There is simply a difference whether internal or external!

The ups and downs remain for the little ones!
0.11 or 0.22 correction every few seconds!
You can see that on the chart.

[ME]

its so i can hook up the bluepill to my pc via rs-232 to look at the nema data etc, I wondered if the voltage levels from the bp pins that carry the sat data  will be convertwd to rs-232 levels with the max 232, i assume its ttl levels?, Thanks.

[KungFuJosh]

You should check the configuration for the lil guy. Those curves don't look right to me. On my first (shorter) screenshot, you can see more detail. Either way, I get around 600uHz PP, but no dramatic curve like yours shows.

What's the sample rate on your counter? What does the other GPSDO look like?

[Kurt_!]

its so i can hook up the bluepill to my pc via rs-232 to look at the nema data etc, I wondered if the voltage levels from the bp pins that carry the sat data  will be convertwd to rs-232 levels with the max 232, i assume its ttl levels?, Thanks.

It's best to buy an FTDI adapter or CP2102. They don't cost much...

[Kurt_!]

You should check the configuration for the lil guy. Those curves don't look right to me. On my first (shorter) screenshot, you can see more detail. Either way, I get around 600uHz PP, but no dramatic curve like yours shows.

What's the sample rate on your counter? What does the other GPSDO look like?

I'll have to take a closer look. The rate is per second. Maybe I need to adjust the 1.05 in the program.
Do you also have the corrections every few seconds: 0.00 - 0.11 - 0.22?
on the display.