Mobius Super Capacitor.

@russ331 doesn't know what he's gotten himself into. He won't be able to stop now. And we're all depending on him! He'll be an old, old man and still providing updates on the status of his Mobi. And we'll all be reading them. :):D

I'll probably still be running my Mobi at that time too!:happy:
 
I've found two recent examples of it failing to auto record after sitting for an extended period. The first was 4 days and yesterday was 7 days. The date time hasn't been lost in either case. In both cases the Mobius has auto started perfectly for the rest of that day's trips (after I've noticed the red light not flashing and manually started midway on the first trip.)

It just started auto recording fine when I went to remove it to check the files. I'll have to try and remember to check it before starting the engine next time. It's wired into the BCM lighting circuit so I'll have to see if that circuit is behaving abnormally when the vehicle's battery drops in charge.

It does reset the time/ date. It's always after the vehicle has sat for an extended period- it's never happened when it's driven every couple of days (so I don't think it points to an intermittent cable issue.)

I have also got a "delay on" timer to prevent ignition power interruptions/ spikes affecting the power up sequence (as a fail safe.) But it does appear to be a booting issue of some sort given the power button will start it, power is obviously being applied to the Mobius. I'll try wobbling the cable next time it happens before pushing the power button.

Now I've got two Mobius in the same vehicle I can also swap them around to see if the fault moves with the camera.

I've isolated the problem to only occurring when the Mobius capacitor's charge level is low.

If I open the doors and let the car sit (for around 15 minutes) before starting the engine the Mobius will start up okay and then continue recording after the engine is started. However, if I just unlock the vehicle and go straight to start the engine the Mobius will start, crash as the engine starts and fail to restart. It's wired to come on with the interior lights- so as soon as the vehicle is unlocked. The charge level of the car's starter battery doesn't make any difference.

I'll try removing the delay timer and see what difference that makes.
 
1 Caps out of spec
a- Internal resistance too high
b-Unable to hold sufficient charge

2 Mobius cap charging voltage regulation circuit out of spec
a- Not allowing sufficient charring
b- Plug-in cap/battery connector dirty or has developed high resistance from failing solder

3 Insufficient power at Mobius USB power port
a- Bad P/S
b- Bad USB cable
c- Plug--in USB connection dirty or has developed high resistance
d- Insufficient power going to P/S

My guess is 1a or 3b. Caps do wear over time and could have been low grade to start with. USB cables can degrade over time with cheap ones doing this rather quickly. 3c is a possibility with the lead-free solder being used in the construction of all e;electronics these days. This could also happen anywhere on the PCB (look up "Tin Whiskers")

Phil
 
what sort of delay timer are you using and how is it currently configured?

Hi Jokiin, it's one of these:


From memory it's set for about 3 seconds delay on?

I was experimenting with a different capacitor equipped Mobius out of the vehicle- randomly powering it up, removing power and then reapplying. If power is reapplied when the rear red LED is still on it misses the power reapplication and seems to just sit there charging (green LED on side lit.) The capacitor being fully charged or completely discharged didn't seem to make any noticeable difference.

I'm wondering if the delay circuit is missing the voltage variation/ ripple with engine starting but the Mobius is somehow more susceptible to it with a low capacitor charge level? Or the delay circuit behaviour changes after it's been sitting inactive for a long period?

I might just have to switch it to the same IGN ON source the rear Mobius runs off. It doesn't seem to be affected by the engine starting (but I'll lose the bonus of the front one staying powered for about 15 minutes after I leave the car.)

Ironically the working rear Mobius is going to have to be replaced with something else as the radiated noise kills my DAB radio sensitivity.
 
just want to make sure I understand what you're doing correctly, you're using a timer to delay power from turning on to the camera for 3 seconds, is that correct?
Yes. The theory being if there's a power drop-out it's a minimum of 3 seconds- to give the Mobius time to "sort itself out".
 
Yes. The theory being if there's a power drop-out it's a minimum of 3 seconds- to give the Mobius time to "sort itself out".

this helps in some scenarios but not all, the problem happens when the camera initiates a shutdown command and then receives power again and it doesn't know what to do, rather than a startup delay timer a better approach is to setup a delay off timer, need a 3 wire timer, anytime power is applied to the accessory feed it holds power for X number of seconds before shutting down, this counters any power cut situations you're likely to encounter, cranking the engine etc as it will always keep power to the camera for whatever time you have set, when you do power off it does mean that the camera will continue to record for whatever time you have set as well, doesn't need to be much, 5 to 10 seconds is ample but that's not really a negative, just something to keep in mind when you want to eject the card to make sure it has shutdown first

the situation is fixable in firmware but they don't seem to know how to do it, a few dollars worth of parts and a bit of setup though and you can get around the problem without too much trouble
 
@jokiin Thank you for the clarification.

IIRC @Isoprop had mentioned more than once that the size of the capacitor is to blame. Maybe he's also been led to believe this as the information could be coming from the guys at Mobius.

If this is indeed true for the Mobius, they seem to have dropped the ball long before the Mobius 2.
 
@jokiin Thank you for the clarification.

IIRC @Isoprop had mentioned more than once that the size of the capacitor is to blame. Maybe he's also been led to believe this as the information could be coming from the guys at Mobius.

If this is indeed true for the Mobius, they seem to have dropped the ball long before the Mobius 2.

A larger capacitor would allow a different and simpler work-around within the current limitations of its hardware and firmware.
 
A larger capacitor would allow a different and simpler work-around within the current limitations of its hardware and firmware.

a larger capacitor would not actually fix the problem, it's the shutdown/startup sequence that needs modifying, having a larger reserve capacity of power won't change that at all, we had the identical issue when we first tested the GC and had to rewrite the process in the firmware
 
a larger capacitor would not actually fix the problem, it's the shutdown/startup sequence that needs modifying, having a larger reserve capacity of power won't change that at all, we had the identical issue when we first tested the GC and had to rewrite the process in the firmware

My analysis of Mobius with capacitor is that if the capacitor could hold enough charge to run the cam for more than 10s it would be possible to use the PC program's power-off-disconnect 10s option and the camera wouldn't shut down with momentary power fluctuations. But the cap only holds enough power for maybe 5-6s of operation so power-off-disconnect has to be set to immediate otherwise the last file doesn't save properly.
So my experiments suggest that Mobius could be 'fixed' with either a double-size cap using existing firmware, or a modification to the firmware to allow couple of seconds power-off-disconnect instead of 'immediate' which is too short to cope with brief power interruptions or '10s' which is too long for the cap to keep the cam running.

Another weak point of the small-ish cap is that it takes around 20-30s to reach full charge and during that time if an accident occurred the cam might not save the last file properly.

Mobius is relatively quick to power up - about 5s - so those initial few seconds would be the only risky period of time where power fluctuation might upset the cam.
 
My analysis of Mobius with capacitor is that if the capacitor could hold enough charge to run the cam for more than 10s it would be possible to use the PC program's power-off-disconnect 10s option and the camera wouldn't shut down with momentary power fluctuations. But the cap only holds enough power for maybe 5-6s of operation so power-off-disconnect has to be set to immediate otherwise the last file doesn't save properly.
So my experiments suggest that Mobius could be 'fixed' with either a double-size cap using existing firmware, or a modification to the firmware to allow couple of seconds power-off-disconnect instead of 'immediate' which is too short to cope with brief power interruptions or '10s' which is too long for the cap to keep the cam running.

Mobius is relatively quick to power up - about 5s - so those initial few seconds would be the only risky period of time where power fluctuation might upset the cam.

you're kind of on the right track, I'd say you've probably better understood the issue than their engineers have at this stage

Another weak point of the small-ish cap is that it takes around 20-30s to reach full charge and during that time if an accident occurred the cam might not save the last file properly.
.

larger caps take longer to charge, the smaller caps actually have an advantage here, I keep hearing the excuse about the caps being too small but there are other cameras out there using the identical size caps without issue
 
....larger caps take longer to charge, the smaller caps actually have an advantage here, I keep hearing the excuse about the caps being too small but there are other cameras out there using the identical size caps without issue

Curiously, my JooVuu X cams manage to charge their caps in about half the time it takes my Mobius cams - that's based on how soon after receiving power the cam can have power removed and still be able to save the file. I've lost the file with the exact figures but from memory it was something like 10-15s after receiving power for the JooVuu and 20-30s for the Mobius.
 
Curiously, my JooVuu X cams manage to charge their caps in about half the time it takes my Mobius cams - that's based on how soon after receiving power the cam can have power removed and still be able to save the file. I've lost the file with the exact figures but from memory it was something like 10-15s after receiving power for the JooVuu and 20-30s for the Mobius.

different hardware, different firmware, not directly comparable for the issue that the Mobius has
 
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