ANDROMEDA shuts down when voltage drops to 12.4V

SM3PZG
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ANDROMEDA shuts down when voltage drops to 12.4V

Postby SM3PZG » Sun Sep 18, 2022 3:38 pm

I am using a Diamond GSV3000 30A continuous power supply to drive the Andromeda. In the manual it says "input voltage must be 13.8vdc +/- 5%". That is 13.11-14.49 vdc.

In RX Thetis shows 13.7-14V. Tuning 100W voltage drops to 12.9-13.2V 22.5A Tuning 10W 13.4-13.6V 9A

When running CW at 100W output the Amdromeda PC suddenly shut down and rebooted. Very annoying. The second time this happen I suspected voltage so I tested lowering the voltage gradually until shutdown. At 12.4V the Andromeda PC shuts down and reboots.

Should it really be that sensitive to voltage fluctuations? You would think it would run on at least 12VDC. If so could someone recommend a very stable 13.8V 30A power supply?

I guess I could turn up the voltage a little to 14.2-14.3V but then I am near the upper limit and that doesn't feel comfortable.

73/Sam
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w-u-2-o
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby w-u-2-o » Sun Sep 18, 2022 4:30 pm

First things first: don't trust the radio voltage reading. Put a voltmeter at the power input connector on the back of the Andromeda and tell us what that says under all of the same conditions you measured above.
SM3PZG
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby SM3PZG » Sun Sep 18, 2022 5:02 pm

Your right. GSV3000 at 13.8V voltmeter say 13.73V. TX 100W voltmeter say 13.71V but Thetis voltmeter fluctuates 12.9V to 13.3V. So GSV3000 is stable.

Any suggestions to the problem?
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w-u-2-o
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby w-u-2-o » Sun Sep 18, 2022 5:34 pm

Do you see any fluctuations on the voltmeter when running CW that might indicate the rapid on/off nature of the current draw is causing problems for the GSV3000?

If the answer to that is "no", then an RFI problem of some type would be an additional consideration, in which case trying a few ferrites on both the power cable and antenna cable where they exit the Andromeda is a good test. If that "Band-Aid" fix works, then you might look for a more root cause of RFI.
SM3PZG
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby SM3PZG » Sun Sep 18, 2022 7:53 pm

Nope, there is no fluctuation on voltmeter when running CW. I have never had any RFI problems before. The 0.5-0.9V fluctuation when running 100W is on all bands 160-6m. Running 10W fluctuation is less 0.2-0.4V. Running 1W 0.1-0.3V. Even in RX with 0A it 0.1-0.3V. The load in the I7 processor is only between 5-10%

Have a Expert 1.3K-FA amp. It only need 9-14W drive for 1KW output. No RFI problems and no shutdown. It only happened when running with 100W drive.

Tried ferrites rings as you suggested but no difference.

Maybe someone else with a Andromeda can check voltage fluctuation reading?

73/Sam
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w-u-2-o
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby w-u-2-o » Sun Sep 18, 2022 8:28 pm

SM3PZG wrote:Have a Expert 1.3K-FA amp. It only need 9-14W drive for 1KW output. No RFI problems and no shutdown. It only happened when running with 100W drive.

Perhaps it is an internal RFI problem of some sort. Does it happen with phone? Digital? Or only CW?

Of course the easy answer is just use your amp, but I can understand you wanting it to work properly on its own.
SM3PZG
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby SM3PZG » Mon Sep 19, 2022 6:08 am

Yes its the same on all modes. Also just by tuning. The shutdown happen on 15m were the PA was not calibrated correctly. Full drive gave 125W output. Have recalibrated PA on all bands to about 95W with 100% drive and increased voltage to 14V so hopefully that will solved the problem.

I would guess the PC gets to low voltage and reboots if the processor load suddenly increases for some reason - at the same time as full power output.

73/Sam
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w-u-2-o
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby w-u-2-o » Mon Sep 19, 2022 11:15 am

SM3PZG wrote:The shutdown happen on 15m were the PA was not calibrated correctly. Full drive gave 125W output.
So the real reason for all this was improper calibration?

Understand that the built in RF power meter isn't much more accurate than the built in voltage meter. To do a good job of calibration an accurate external RF power meter is required (which can also be used to calibrate the internal power meter).
SM3PZG
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby SM3PZG » Mon Sep 19, 2022 6:35 pm

Well I don´t know the reason. I think there might be a problem when the 7000DLE MK2 and PC with i7 processor share the same DC power source. On all other models SDR and PC have separate power supplies.

The volt indications seems fairly accurate. Right now voltmeter say 14.06V on DC input and volt indicator in Thetis fluctuates between 13.9-14.1V. I am curios if anyone else with a Andromeda have the same issue.

What about your station Scott, any voltage fluctuations when running 100W?

73/Sam
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w-u-2-o
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby w-u-2-o » Mon Sep 19, 2022 7:35 pm

I have both an 8000 and a 100D. Neither have ever shown any issues in that respect. However I never run them without an amp, so I'm not a good test case.
N7CXI
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Re: ANDROMEDA shuts down when voltage drops to 12.4V

Postby N7CXI » Wed May 31, 2023 6:41 am

Late to the game here, but my Andromeda does the same thing at 100W output into 50 ohms.
I reset the PA calibration to 90W max on all bands, and since then it's been fine.

I should mention I don't run digital or CW with the Andromeda, just SSB.

73,
Jim N7CXI

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