Maina intermittent issue

[mikekolling]

Excellent ok, i will monitor it now.

I will buy some LEDS and fit. Will be back in touch in a few days.

Once again, thankyou, you have been very helpful!

[sebba]

You're very welcome
Fair wind

[mikekolling]

You're very welcome
Fair wind

Ok, the weekend

Took the unit to the boat, connected it up via the breakout board to the RPI and all day Saturday it ran faultlessly picking up lots of AIS signals.

Disconnected it from the RPI at about 13:00 and left it running on its own just from the Breakout board.

It ran from 10:00 to 16:00 and then died.

I cycled the power off and on and it started up again immediately.

Went out for the evening with it running, came back at about 21:00 and it had stopped again.

Again, cycled the power and it restarted.

Left it overnight running.

I did switch on a Battery Charger during the night, should i try fitting an independent 12V PSU between the Engine Battery and the unit to isolate any spikes or over voltage (although the Battery Charger was only 13.8V)

If so, any advice on a suitable device to try?

This morning 06:30 it had stopped again and this time I could not restart it. Cycled power, tried different power supply ie from a mains 12V power supply all sorts no good.

I checked with multimeter and there was a good 12V on the breakout board.

Drove home 1h30mins and plugged it in on mains 12V PSU and its running again.

So I think there is an issue if it’s been plugged in a long time.

Overnight it would not have overheated due to overnight temperature it just seems to fail after a long period.

i have ordered a 12v-12v isolated PSU and lets see if that helps.

So, questions…


Does anyone have a spare Aerial PCB I can try?

Can I return just the PCB from the aerial for someone to test or check out?

Is there anything else I can try to fix this??


It’s a shame as it worked so well yesterday.

Mike

[mikekolling]

Hi
I had the unit plugged in all night and still running this morning.
So we plainly have an issue on the boat.
Boat is motor boat with twin engines. These engines are 12V and charge the domestic electric system 24v via two Victron Orion 12v to 24V chargers
Currently RPI and Maiana are powered from the engine batteries 12V but ,.... the unit is located on my dashboard which is 2meters above where the Orions are located in the bilges.
So i have ordered one of these  MEAN WELL SD Power Supply Converter， SD-15A-12 15W 1.25A : Amazon.co.uk: Computers & Accessories

I am hoping that will isolate any noise and spikes from the 12V supply to this system.

Is there any mileage in moving the system to a different part of the boat?

Mike

[sebba]

I really have to idea what to say.
Physically, where is Maiana mounted? Is it outside of the boat? Is not really ok to have it inside the boat. The antenna have to be placed outside, as far as possible from other antennas.

[mikekolling]

   

I really have to idea what to say.
Physically, where is Maiana mounted? Is it outside of the boat? Is not really ok to have it inside the boat. The antenna have to be placed outside, as far as possible from other antennas.

Hi

See attached image, there are other antennas there. Not sure where else i could put it

Mike

[sebba]

The connection between Maiana and Pi is made through the UART2USB adapter right now?
I somehow suspect a ground loop in the wiring.
Can you draw a connection diagram for Pi and Maiana? Including the power lines and the connection between

[mikekolling]

The connection between Maiana and Pi is made through the UART2USB adapter right now?
I somehow suspect a ground loop in the wiring.
Can you draw a connection diagram for Pi and Maiana? Including the power lines and the connection between

Its through the Breakout board through the USB port.

i will do a drawing

[mikekolling]

Ok, update
Have been running it at home on clean AC 12V PSU since the weekend.  The Maiana running on its own has crashed a few times and normally needs a period of power off (normally greater than 30mins) and then will fire up again. Its deceptive as you think its not running but it takes a few minutes to start up. When you first switch it on, the AIS led flickers very briefly, if you see that - its pretty certain its going to fire up.

I have now put it back on the RPI and Macarthur hat again as we know its not them that is the issue.

Is there any way to write a script to track anything to a log so that we may be able to see why it crashed? eg Voltage feed or the Radio Noise, i see there is a setting in the Maiana app to 'detect noise' - i have this switched on but you only see the notifications within the RPI desktop. Is there a way to log these or is it logging these already?

if we could track any issues, i could write a script to switch it off for a bit before it dies.

thanks in advance.

[mikekolling]

I have now set up a NodeRed, InfluxDb and Grafana to track the Maiana Channel A and B Noise figures. Can you confirm what Chatgpt says is correct below? 

Great question — and now that you're logging RF noise floor values from the Maiana SDR, it's absolutely worth understanding what those numbers actually mean in practice.

? What the Maiana "noiseFloor" readings represent
Each noiseFloor value (for Channel A or B) is an RSSI-like indicator of background RF power measured in the band it's currently scanning.

Units: not dBμV or dBm, but a relative number between ~20 to 100+

Lower = better (less ambient RF noise)

Higher = worse (more interference)

Think of it as “how noisy is the air around this receiver?”

? What are good or bad values?
Noise Floor Value Interpretation Typical Source
20–40 ? Excellent — quiet RF environment Open sea, rural mooring
40–60 ? Moderate — slight RF activity Nearby vessels, low-level interference
60–80 ? High — possible interference Marina, AIS/GSM/Wi-Fi congestion
80+ ? Very high — signal reception degraded DC noise, inverters, USB junk, radar

Rule of thumb: if your noise floor is over 60, weaker signals like AIS Class B may be drowned out.