GPSDO Tutorial?

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PaulManc
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Re: GPSDO Tutorial?

Postby PaulManc » Tue Sep 26, 2023 10:06 pm

w-u-2-o wrote:200D, 7000, 8000, Andromeda, and G2 all use the same 10MHz input circuit. You should have no problem.


Forgive me for asking again, Scott.

What should the input impedance of the 10mhz ref input be is it 50ohms or something else? I plan to use the Leo Bodnar GPSDO

Cheers,
Paul
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w-u-2-o
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Re: GPSDO Tutorial?

Postby w-u-2-o » Tue Sep 26, 2023 11:50 pm

The Bodnar is 50 ohm output impedance and the ANAN is high impedance as delivered from the factory. Nevertheless that combo should work just fine as is. You may have to adjust the Bodnar drive level.
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W9BHI
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Re: GPSDO Tutorial?

Postby W9BHI » Thu Sep 28, 2023 12:41 am

There is a 2 pin header on the board that places a 50 ohm termination on the external ref.input.
KC2QMA
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Re: GPSDO Tutorial?

Postby KC2QMA » Thu Sep 28, 2023 10:28 am

I have the one with the 2 10mhz outputs and this unit and works fine with G2.
It works with as little as 8mA of drive, outputs a square wave.
Just put the GPS antenna in your window or outside, connect GPSDO to radio via BNC to SMA cable to the 10mhz input on the back of the radio go into Thetis and enable External Reference and your done!
simple plug and play!
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PaulManc
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Re: GPSDO Tutorial?

Postby PaulManc » Sat Sep 30, 2023 10:36 pm

w-u-2-o wrote:The Bodnar is 50 ohm output impedance and the ANAN is high impedance as delivered from the factory. Nevertheless that combo should work just fine as is. You may have to adjust the Bodnar drive level.


As usual, BIG Tnx 73
Paul
Manchester
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KA9UVY
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Re: GPSDO Tutorial?

Postby KA9UVY » Mon Jan 22, 2024 7:18 pm

I have been experiencing since day one my Anan 7000DLE MKIII locking in two different places when powered on, I typically just run a calibration with WWV in Thetis to resolve the issue and it stays OK most of the time but very seldomly jumps back off again the correction or offset is to around 0.99997656 instead of 10.000001 or so.
Anyway I had purchased a Leo Bodnar GPS 10 Mhz source many months ago but with limited time to spend with my ANAN, I just hooked it up tonight.
My Results:
Radio is off frequency by this same margin when observing WWV but I cannot seem to enter a correction factor into HPSDR when use ext source is checked?
Pardon me for not seeing much of anything on here about using an ext source and still applying a correction factor in Thetis to get everything to be correct.?
Thetis defaults to 1.00000000 if I check the ext source and I can see the WWV carrier jump to the left of the center crosshair then my radio is clearly off frequency. It looks like I need a correction factor applied to my ext source to get this radio ON freq and hitting the reset button does nothing.
My Leo Bodnar software panel is pretty much exactly the same as the one posted earlier in this thread.
Please point me in the right direction. Thanks
Anan 7000DLE- MKIII
Thetis 2.10.3.5 u2
FW 2.2.2A
Protocol 2 v 3.9

73, Robert
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W4WT
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Re: GPSDO Tutorial?

Postby W4WT » Tue Jan 23, 2024 10:40 pm

Robert, I assume you have tried adjusting the adjustment that is just below the option "Using ext 10Mhz ref" and not the "Correction Factor" adjustment when you have the GDO connected? I have a 7000 MK II and I use a GDO and have no trouble moving the "zero" around with the adjustment factor in the bottom left of the Calibration Tab. My correction is small but it did take just a bit to zero it to WWV with my GDO; 1.00000003. You shouldn't hit the reset button after entering your offset unless you want to clear it.

I'm assuming you have the Thetis version with this correction area in the Calibration tab. I don't remember which version it came out in. Before that version, there was only the "Correction Factor" window which I don't believe affected the external input at all.

Joe, W4WT
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KA9UVY
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Re: GPSDO Tutorial?

Postby KA9UVY » Wed Jan 24, 2024 3:09 am

Hi Joe, Thanks for the reply, the version I am running is listed in my signature and I believe its the newest out or close.
My calibration section is as follows:
freq cal.jpg
freq cal.jpg (135.84 KiB) Viewed 886 times



When I check to use the external 10 Mhz Ref, It will not change if I move the correction factor up or down and it actually reverts back to 1.0000000

If I calibrate with WWV it adjusts and stays put but my radio sometimes jumps off.
I can't use my GPSDO at all with out a correction factor in HPSDR?
Anan 7000DLE- MKIII
Thetis 2.10.3.5 u2
FW 2.2.2A
Protocol 2 v 3.9

73, Robert
KA9UVY
W4WT
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Re: GPSDO Tutorial?

Postby W4WT » Wed Jan 24, 2024 5:25 am

Robert, you may have already tried this but if not give it a go. Save your current database then reset the database and shutdown Thetis. Power cycle the radio then start Thetis. Put just the bare minimum setup info in to get the radio operating and then try the calibration routine again and see if anything changes. If it still fails, reload your database.

This actually sounds like a hardware problem to me. Assuming the database reset doesn't change anything, I would think that even more strongly.

You say it sometimes "jumps", I assume you mean it jumps frequency? If so, how much does the frequency change? Does it ever jump back?

Joe, W4WT
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W9BHI
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Re: GPSDO Tutorial?

Postby W9BHI » Wed Jan 31, 2024 12:36 am

I have a 7000DLE blue face and I am using a Trimble Thunderbolt GPS unit as an external 10MHz reference. It has a sine wave output that was a bit too high so I have the 50 ohm jumper installed on the Orion board and it is now within spec. Thetis is configured with the external 10 MHz enabled. I don't use any offsets because the GPS output is a near perfect 10 MHz and when I check against 10MHz WWV with the mode set to DSB and looking at the phase mode, it is right on frequency. Mind you that my radio was an earlier one that would not recognize a sine wave input on the 10 MHz reference input.
I had the radio in to Doug for a 12 meter output issue and while he had it on his bench, he changed a resistor value in the external reference detection circuit that fixed the issue with it not detecting a sine wave. He notified the factory about the issue and all units after that last run were using the recalculated resistor in that circuit.

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