Cobra CDR-840 questions

Mobius chose a business model that means you're unlikely to find the product in a retail outlet, their choice at the time, their user base is predominantly the RC market so I can appreciate why they went the way they did
 
Perhaps some might want to get a small refund based on a new lower price! I got my $15 today.
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Does anyone know how to get the settings to save.
I have a cobra CDR 840E and it keeps resetting itself to timezone -5:00
I have set it to timezone +1:00 (UK BST) but every time it switches off it resets back to -5:00
This is a pain as I end up with the timestamp being out by 6 hours on my recordings.
I have tried everything I can according to the manual but there is obviously something I am missing, to have the settings persist when the power is turned off.
 
Does anyone know how to get the settings to save.
I have a cobra CDR 840E and it keeps resetting itself to timezone -5:00
I have set it to timezone +1:00 (UK BST) but every time it switches off it resets back to -5:00
This is a pain as I end up with the timestamp being out by 6 hours on my recordings.
I have tried everything I can according to the manual but there is obviously something I am missing, to have the settings persist when the power is turned off.

I have two (long story). One definitely has no trouble keeping time. The other might have gone to -5:00 at some point and I put it back to GMT. I run cams in pairs (two different ones) so if one of the clocks isn't accurate I tend not to worry until I have reason to poke about in the cam's menus.
I'll see if I can find time to poke about in the menus tomorrow.
Could it be something as simple as you're not pressing the correct 'select' button?
Are you using the cam's own power cable or have you changed it? The 840 is fussy about its power supply; it prefers 24AWG cable and can go a bit quirky with 28AWG cable commonly used for mini USB (not enough power getting through).
Meanwhile, try resetting the cam, then starting again by entering date, time and time zone.

Oh - the -5:00 is US time, so if you had an accident you could point that out as a reason why the clock was wrong.

If all else fails, I suppose you could set the clock incorrectly to compensate for the 5hr time shift!
 
I have two (long story). One definitely has no trouble keeping time. The other might have gone to -5:00 at some point and I put it back to GMT. I run cams in pairs (two different ones) so if one of the clocks isn't accurate I tend not to worry until I have reason to poke about in the cam's menus.
I'll see if I can find time to poke about in the menus tomorrow.
Could it be something as simple as you're not pressing the correct 'select' button?
Are you using the cam's own power cable or have you changed it? The 840 is fussy about its power supply; it prefers 24AWG cable and can go a bit quirky with 28AWG cable commonly used for mini USB (not enough power getting through).
Meanwhile, try resetting the cam, then starting again by entering date, time and time zone.

Oh - the -5:00 is US time, so if you had an accident you could point that out as a reason why the clock was wrong.

If all else fails, I suppose you could set the clock incorrectly to compensate for the 5hr time shift!

Thanks,
I'm using the original cables, I tried changing the clock to compensate, but the time gets reset from the GPS based on the timezone. I am also trying to set the format to UK DDMMYYYY.
I've tried all the combinations I can think of. I even tried pressing the orange button as well, but nothing seems to work. I reset default but that sets it back to -5:00.
I can change the settings to what I need, so assume I am pressing the correct menu options and buttons, and it records correctly when I do so. Its just as soon as I switch the power off it resets back to default settings, i.e. -5:00 and MMDDYYYY
 
I just checked one of the two Cobra 840 and it is retaining date and time correctly.
It has been left on GMT (so at the time of this post it's saying around 08:20 which is an hour slow relative to BST) and the timezone adjustment is 0:00.
Serial number of the cam is J408002031.

I'll check the other Cobra 840 later.
 
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I just checked the other Cobra 840 and it is also retaining date and time correctly. Its time settings are the same as the first one.
Serial number of the second cam is J408003379.

But I seem to recall that at one time early in my ownership of one or other of the Cobra 840 cams, one of them had one instance of the time reset you've experienced. But it could have been user error on my part.

Is it possible that you're not driving your car often enough or long enough, resulting in the camera battery not being able to charge fully?
The 840 manual says the battery charge time is three hours, although once it has had a full charge it may well only need a quarter of an hour or half an hour to top up the battery if it is regularly used.

Could it also be due to the battery draining due to motion detection?
 
Is there any way to erase the whole card to start over. I have a lot of saved sections that I don't(have to adjust the sensitivity)want. The card that came with it loaded up and stopped working,put in a SanDisk,was good and then stopped overwriting. Erased open files but found saved files.
 
I bought one of these from CostCo the other day. Did as much as I could to improve video quality (new class 10 SD card, settings, etc) and in daylight video couldn't clearly read signs or license plates unless they were <20 feet away (like what other people noted). I returned it today.
 
after 9 months of perfect use my cdr 840 power supply died. will return this to costco unfortunately .
many people have this problem, do not buy for long tern use.. mine did work as advertised for it's lifespan 9 months....
 
Just picked this up as I have been looking at replacing what I was using prior to this cam. Got it from Costco. Is it general consensus that it will only last 9 months?

Also, does anyone else know where I could get a longer car adapter so I can run the power to it within the liner and dash? (My car is an '09 Nissan Altima)
 
Just picked this up as I have been looking at replacing what I was using prior to this cam. Got it from Costco. Is it general consensus that it will only last 9 months?

Also, does anyone else know where I could get a longer car adapter so I can run the power to it within the liner and dash? (My car is an '09 Nissan Altima)

I have two Cobra 840 still working normally and approaching a couple of years old. The supplied memory cards haven't lasted so well though.

The Cobra 840 can be powered via its mini USB port; use the menus to set USB function to PCAM instead of MSDC. There are many 12v-to-miniUSB power cables available as spares and replacements for dashcams - just make sure the power supply and cable is comparable to the original to ensure enough power gets to the cam. Cheap cables and adapters may have too little output and/or too much cable resistance and not enough power get to the cam, resulting in erratic behaviour.
 
Great, Thanks for the Info and quick reply. If I may ask, how are yours powered while in use in your vehicle?
 
Great, Thanks for the Info and quick reply. If I may ask, how are yours powered while in use in your vehicle?

One of mine lives upside-down on a hybrid mount on top of my dashboard, meaning the supplied cable (with its ferrite bead) can still be used. In that position it generally escapes the worst of the windscreen reflections resulting from my shallow windscreen angle. The Cobra has a 'Screen Rotate' option in its menus so the video comes out the correct way up when the cam is upside-down.

The other has done service as a side-view cam, peeping through the A-pillar window and recording 720p60 which better suits the capture of fast-moving objects passing its field of view, but it has also been a main front cam in our family car and powered by random 'branded' dashcam cables that I've accumulated (Nextbase/DOD, Mio, Transcend).

The hybrid mount on my dash top is the swing-mount section of the Cobra's mount, sitting in the base section of a Mobius adhesive mount. The adhesive alone won't stick securely to the textured dash top, so I put a small screw through the centre of the socket of the mount to secure it.
Anything else that uses the Mobius 'tripod-type' screw-threaded mount will also fit, so in theory I could mount a camcorder on that mount, or a photo-camera, and at times recently I've experimented with a JooVuu X on the same mount.

Picture below showing my dash-top-mounted Cobra 840 and behind-sun-visor-mounted SGZC12RC-V2.
In fact, the speaker and air vent reflections which spoil the image of higher-mounted cams are visible in the picture; the Cobra mostly peeps under the reflections.

-

 
Great Thanks. It looks like you use the 840 (dash mounted) cam as a rear facing (in car) cam. I could put my 840 up in the window as you have your other one, this would help with me running the cable, rather than fusing about for a cable and adapter that would work correctly.

Any thoughts on Video settings. I've changed the settings until I get a 32 gb sd card to fit better one the 8gb to Video: HD 60 FPS, Movie SHQ. Not sure how they will do as far as space on it, I would like it to last longer than 2 hours, maybe 3 to 4. I think I have a 16gb I could put in in the mean time.
 
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Great Thanks. It looks like you use the 840 (dash mounted) cam as a rear facing (in car) cam. I could put my 840 up in the window as you have your other one, this would help with me hiding it, rather than fusing about for a cable and adapter that would work correctly.


The Cobra looks forward out of the windscreen. I don't have a cam watching the interior, although I can swing the Cobra round on its mount.
Most cams are too bulky to tuck away discretely in a corner and may end up getting the owner into trouble for obstructing visibility. The SGZC12RC is a useful exception to the 'brick on a stick' style.

....Any thoughts on Video settings. I've changed the settings until I get a 32 gb sd card to fit better one the 8gb to Video: HD 60 FPS, Movie SHQ. Not sure how they will do as far as space one it, I would like it to last longer than 2 hours, maybe 3 to 4. I think I have a 16gb I could put in in the mean time.

Most people will probably get the best out of it when set to 1080p.
720p60 is only useful for high speed daylight.
Other settings are economy settings which maximise space on the memory card but have lower quality video.

Roughly speaking, an hour of 1080p with the Cobra 840 requires 7GB of memory, so 16GB will store 2-2.5 hours before it starts overwriting the earliest files.

Officially the cam supports up to 32GB memory cards (I haven't tried anything larger) and that will give around 4.5 hours.
 
Ok, cool, I looked up a few differences between the HD 30 and HD 60 FPS. I think I will keep it at the HD 60 FPS/SHQ. See how that does on the drive home today. Thanks again for the info.
 
I've found the following items I would like to get to help with hiding the charger for the 840 dash cam. Any different thoughts?

Mini USB Cable (15ft) - http://www.monoprice.com/product?c_id=103&cp_id=10303&cs_id=1030302&p_id=5450&seq=1&format=2

US Car Adapters
A - 1as (2) Two 2.1 amp ports
http://www.monoprice.com/product?c_id=108&cp_id=10826&cs_id=1082603&p_id=10239&seq=1&format=2
--or--
B - has 2 ports, (1) One 1 amp port and (1) One 2.1 amp port
http://www.monoprice.com/product?c_id=108&cp_id=10826&cs_id=1082603&p_id=10071&seq=1&format=2
 
It's possible that a 15ft USB cable will suffer significant voltage drop over that distance, causing erratic camera operation.
The voltage drop will depend on the size and material of the wire inside.
Most dashcam power cables have 22AWG or 24AWG cable but most USB cables I've seen are (thinner) 28AWG.
Having said that, some cams might work with 28AWG - my wife's car is currently running an experiment with a 16ft 28AWG USB-to-miniUSB cable powering a relatively low-spec cam with low power demand and it seems to work normally over the past couple of weeks.

I would recommend using a genuine dashcam cable where possible, to ensure the cam gets enough power.
 
As for the power, is this correct even though the USB cable is 28/24AWG. Also, would the USB Car adapter with the 2.1 amp ports be better than the 2.1/1.0 amp combo?
 
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