GT680W Super-Capacitor (& Stealth) Mod

Dashmellow

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Location
Uncanny Valley (●_●)
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Dash Cam
Umpteen
I really like the GT680W I bought a few months ago now that it is working well. It started out with some issues and glitches that were resolved when I updated the firmware to v2.7G and since then I've been impressed with how well this little cam functions, how well it seems to be made and the value it provides considering what it cost. It is my first GPS camera and I love the functionality it adds to the dash cam experience. It makes a good companion to the Mobius I'm currently running as a rear cam.

The one major concern with the camera, as most are aware, is the tiny anemic 110mAh battery it comes with. Unfortunately, in order to make the camera so small and so thin the designers decided to make this compromise. I think I would have been happier with a thicker camera with the same height and width dimensions and a bigger battery but we've got what they've given us. Then again, as we know, Li-Po batteries are a problem in dash cams no matter what size they are.

Another concern for me is that I bought this camera just before the release of the all black version with no logos and I really dislike how all the white lettering draws attention to the device when mounted in the windshield. Even though the all black - no logo version is a huge improvement, to my mind the glossy black plastic around the lens and sides and the silver buttons are still a big problem.

So, I decided I would try to modify the GT680W to address these two major complaints. The first order of business was to replace the battery with a super-capacitor and the second part of the plan was to “stealthify” the camera with an all flat black finish. Of course, there were two challenges to overcome. There is no room inside the shell for even the smallest available super-capacitors and the camera is coated with a silicone rubber finish that doesn't hold paint very well.

Shopping around I discovered that it is very difficult to find very small super-capacitors with the required capacity but I finally found a supplier who sells 2.7 volt 10F units that measure 20mm long x 12.5mm wide. I knew going into this project that the only way to run the GT680W with super-capacitors was to “Think Outside The Box”.....literally! My first plan was to simply glue the capacitors to the front of the camera and wire them to the board inside. After that I was going to simply paint the whole camera, capacitors and all, but not long after I started working on this idea I abandoned this approach as being unworkable for several reasons, mostly having to do with the size and shape of the capacitors being just a little to big to fit the front of the camera and the fact that the whole thing would have looked really ugly.

Of course, before I could proceed here the one big question that needed to be answered was whether or not the GT680W would even work with super-capacitors. So, I fabricated two caps into a 5V/20F “cell” as seen in the photos using some fine wire, heat shrink tubing, electrical tape and a thin piece of copper and connected it to the camera's circuit board to see what would happen. At first nothing happened at all when I switched on the camera but happily I quickly realized that I was just being too impatient. I found that I needed to wait for at least a good seven minutes or so until the capacitors charged up to their rated capacity for the first time. So now I tried it again and this time the camera worked great! It locks GPS, it holds the date and time when switched off and it saves the last file after the power supply is removed. I was in business!

So after some head scratching I finally decided the best location for the capacitors would be away from the camera - on the back of the mount itself, attached with Dual-Lok tape so the capacitors are quite secure but the camera can still be removed from the mount. This has proved to be a viable and more elegant solution than gluing the caps to the front of the camera. And since I have no use for the LED emitter included on this camera I removed the small oval diffusion lens on the front of the case which provided for easy access to wire the super-caps to the circuit board without having to modify or drill the shell in any way. The little LED lens is simply attached with two small screws and is therefore very easy to remove.

OK, so now the problem of applying a flat black finish. The GT680W is coated with a flat black rubberized silicone coating that has a colored enamel logo and white lettering applied. This type of rubberized coating is very difficult to paint because it will not allow any finish that is applied to it to adhere well. When I first got this camera I tried various solvents to see if I could remove just the logos but nothing really worked as I'd hoped so I knew I would need to paint the whole camera if I wanted it all black. Of course, I knew already that this might be impossible because it is coated with that rubberized silicone, so I used pure acetone solvent to dissolve and completely remove the rubber coating from the front shell piece down to the plastic surface. This is a messy job, not for the faint of heart as it takes a fair amount of rubbing with acetone and as you expose the plastic below the rubberized coating the surface of shell itself will begin to melt! One needs to be very careful or you could ruin the casing. Nevertheless, I was able to remove the rubber coating with the shell not looking too worse for wear but it did end up with some subtle ripples and an ugly “embossed” fingerprint that had to be dealt with.

The next step was to sand down the case with very fine emory cloth to clean up the mess I'd made of everything with the acetone. Once the case was smooth again I used #00000 grade steel wool to polish away any sanding scratches and swirls before painting. Once that was done, I blew off all the dust with compressed air and then wiped it down well with denatured alcohol and let it dry before applying the black paint....two coats. In addition, I also masked off the exposed camera circuit board and ports so I could paint the shiny black plastic sides of the camera itself along with those silver buttons. I used Rust-Oleum Ultra-Flat Specialty Camouflage paint which is the most durable, most non-reflective flat black paint I have found. This paint will dry to the touch in 20 minutes and will fully dry in 24 hours on most surfaces but when applied to plastic they recommend waiting 5-7 days for maximum adhesion and durability. Excellent stuff for this purpose.

So, for now I plan to install the GT680 full time as my front camera with one of my Mobius cams in the rear. For the first time in my several years of using dash cams both of my units will be running on super-capacitors and I no longer have to worry about battery related issues, especially now that the warm weather is on the way........and the GT680W is much more stealthy than it started out!

front-new.jpg

newback2.jpg

The case wasn't completely snapped back together in this early photo.
camcapped.jpg

capmounted1.jpg

super-caps.jpg
 
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Wow. I am very impressed with your work and achievements. Great job!
 
I really like the GT680W I bought a few months ago now that it is working well. It started out with some issues and glitches that were resolved when I updated the firmware to v2.7G and since then I've been impressed with how well this little cam functions, how well it seems to be made and the value it provides considering what it cost. It is my first GPS camera and I love the functionality it adds to the dash cam experience. It makes a good companion to the Mobius I'm currently running as a rear cam.

The one major concern with the camera, as most are aware, is the tiny anemic 110mAh battery it comes with. Unfortunately, in order to make the camera so small and so thin the designers decided to make this compromise. I think I would have been happier with a thicker camera with the same height and width dimensions and a bigger battery but we've got what they've given us. Then again, as we know, Li-Po batteries are a problem in dash cams no matter what size they are.

Another concern for me is that I bought this camera just before the release of the all black version with no logos and I really dislike how all the white lettering draws attention to the device when mounted in the windshield. Even though the all black - no logo version is a huge improvement, to my mind the glossy black plastic around the lens and sides and the silver buttons are still a big problem.

So, I decided I would try to modify the GT680W to address these two major complaints. The first order of business was to replace the battery with a super-capacitor and the second part of the plan was to “stealthify” the camera with an all flat black finish. Of course, there were two challenges to overcome. There is no room inside the shell for even the smallest available super-capacitors and the camera is coated with a silicone rubber finish that doesn't hold paint very well.

Shopping around I discovered that it is very difficult to find very small super-capacitors with the required capacity but I finally found a supplier who sells 2.7 volt 10F units that measure 20mm long x 12.5mm wide. I knew going into this project that the only way to run the GT680W with super-capacitors was to “Think Outside The Box”.....literally! My first plan was to simply glue the capacitors to the front of the camera and wire them to the board inside. After that I was going to simply paint the whole camera, capacitors and all, but not long after I started working on this idea I abandoned this approach as being unworkable for several reasons, mostly having to do with the size and shape of the capacitors being just a little to big to fit the front of the camera and the fact that the whole thing would have looked really ugly.

Of course, before I could proceed here the one big question that needed to be answered was whether or not the GT680W would even work with super-capacitors. So, I fabricated two caps into a 5V/20F “cell” as seen in the photos using some fine wire, heat shrink tubing, electrical tape and a thin piece of copper and connected it to the camera's circuit board to see what would happen. At first nothing happened at all when I switched on the camera but happily I quickly realized that I was just being too impatient. I found that I needed to wait for at least a good seven minutes or so until the capacitors charged up to their rated capacity for the first time. So now I tried it again and this time the camera worked great! It locks GPS, it holds the date and time when switched off and it saves the last file after the power supply is removed. I was in business!

So after some head scratching I finally decided the best location for the capacitors would be away from the camera - on the back of mount itself, attached with Dual-Lok tape so the capacitors are quite secure but the camera can still be removed from the mount. This has proved to be a viable and more elegant solution than gluing the caps to the front of the camera. And since I have no use for the LED emitter included on this camera I removed the small oval diffusion lens on the front of the case which provided for easy access to wire the super-caps to the circuit board without having to modify or drill the shell in any way. The little LED lens is simply attached with two small screws and therefore very easy to remove.

OK, so now the problem of applying a flat black finish. The GT680W is coated with a flat black rubberized silicone coating that has a colored enamel logo and white lettering applied. This type of rubberized coating is very difficult to paint because it will not allow any finish that is applied to it to adhere well. When I first got this camera I tried various solvents to see if I could remove just the logos but nothing really worked as I'd hoped so I knew I would need to paint the whole camera if I wanted it all black. Of course, I knew already that this might be impossible because it is coated with that rubberized silicone, so I used pure acetone solvent to dissolve and completely remove the rubber coating from the front shell piece down to the plastic surface. This is a messy job, not for the faint of heart as it takes a fair amount of rubbing with acetone and as you expose the plastic below the rubberized coating the surface of shell itself will begin to melt! One needs to be very careful or you could ruin the casing. Nevertheless, I was able to remove the rubber coating with the shell not looking too worse for wear but it did end up with some subtle ripples and an ugly “embossed” fingerprint that had to be dealt with.

The next step was to sand down the case with very fine emory cloth to clean up the mess I'd made of everything with the acetone. Once the case was smooth again I used #00000 grade steel wool to polish away any sanding scratches and swirls before painting. Once that was done, I blew off all the dust with compressed air and then wiped it down well with denatured alcohol and let it dry before applying the black paint....two coats. In addition, I also masked off the exposed camera circuit board and ports so I could paint the shiny black plastic sides of the camera itself along with those the silver buttons. I used Rust-Oleum ultra-flat specialty Camouflage paint which is the most durable, most non-reflective flat black paint I have found. This paint will dry to the touch in 20 minutes and will fully dry in 24 hours on most surfaces but when applied to plastic they recommend waiting 5-7 days for maximum adhesion and durability. Excellent stuff for this purpose.

So, for now I plan to install the GT680 full time as my front camera with one of my Mobius cams in the rear. For the first time in my several years of using dash cams both of my units will be running on super-capacitors and I no longer have to worry about battery related issues, especially now that the warm weather is on the way........and the GT680W is much more stealthy than it started out!

View attachment 4841

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Nice intruction for those who want to paint their dashcams !

I wonder if can run supercaps cables on the top part of dashcam, near mini-usb port for more stealth look ?

Nice job and great out of box thinking.
 
Just for the sake of correct info your two caps double the voltage and halve the impedance so you end up with 5.4v and 5F

Thanks for the correction Jokiin. I'm not much of an electronics guy......just a tinkerer. :)
 
Nice intruction for those who want to paint their dashcams !

I wonder if can run supercaps cables on the top part of dashcam, near mini-usb port for more stealth look ?

Nice job and great out of box thinking.

It's a little tricky with the cables because the super-cap leads are delicate and not really meant to be bent like that. I was afraid to stress them too much. I left them long because I wasn't keen on the idea of soldering too close to the terminals on the caps, except where there was copper protecting the top. I figured I would see how it all goes. It can always be rewired. At this point I don't really think the cables are so much less stealthy as much as just ugly. :) At least it works! That was the main thing.
 
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Nice intruction for those who want to paint their dashcams !

I wonder if can run supercaps cables on the top part of dashcam, near mini-usb port for more stealth look ?

I was just re-reading your post and realized I might not have understood what you meant. Perhaps you were suggesting drilling holes on the top of the camera near the USB port and running the cables straight down into the case. That would work! I was a little afraid of doing anything that might damage the camera so the LED lens opening seemed like a convenient, non-destructive approach. After I use the camera like this awhile I may try a different wiring plan. The black "cables" are just heat shrink tubing over the wires but using sheathed flexible wire soldered closer to the caps might make it easier.
 
Perhaps you were suggesting drilling holes on the top of the camera near the USB port and running the cables straight down into the case. That would work! I

Correct. I meant it like you wrote. Sorry for my bad english.
 
Correct. I meant it like you wrote. Sorry for my bad english.

No, No..it wasn't your bad English. Stop apologizing about that already! Your English is just fine.:)

The more I think about it I remember now I was worried that drilling down through the top there isn't much room between the GPS plug and the USB port. Also, when you slide the mount off the camera you need to have some room near the mount as well as room to press your finger against the release lever. I think if I just used those very thin wires with no heat shrink tubing it might work though.
 
Pretty cool man! Love tinkering too.
 
I have an interesting update to my experience with my GT680W super-capacitor mod.

Today the weather finally lifted, the sun came out and I had a little time to install the capacitor powered 680W in my vehicle. I am thrilled to report that the mod works much better than expected!

All of my testing so far has been indoors with an AC powered 1 Amp USB to microUSB adapter. Like I've said, it works fine, it saves the last file the camera was recording and locks GPS properly. The only thing I've noticed of concern is that when I pulled the plug and disconnected the power from the camera it would shut down almost instantly. I've tested it several times to make sure the last file was indeed being saved and it was...but still, I was hoping for a little better performance than that from those super-caps. So today, for reasons that are not yet clear, with the camera now ensconced in my vehicle when I turn off the ignition I get a full 10 seconds of run time from the camera AFTER the power is off! How cool is that?

I'm running the camera from a dual port USB adapter that is running a Mobius (super-capped) in the rear and the GT680W up front. One port is 1 Amp while the other is 2.1 Amps. I consistently get the same ten second shut down from either the 1 Amp or 2.1 Amp port.
 
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I have an interesting update to my experience with my GT680W super-capacitor mod.

Today the weather finally lifted, the sun came out and I had a little time to install the capacitor powered 680W in my vehicle. I am thrilled to report that the mod works much better than expected!

All of my testing so far has been indoors with an AC powered 1 Amp USB to microUSB adapter. Like I've said, it works fine, it saves the last file the camera was recording and locks GPS properly. The only thing I've noticed of concern is that when I pulled the plug and disconnected the power from the camera it would shut down almost instantly. I've tested it several times to make sure the last file was indeed being saved and it was...but still, I was hoping for a little better performance than that from those super-caps. So today, for reasons that are not yet clear, with the camera now ensconced in my vehicle when I turn off the ignition I get a full 10 seconds of run time from the camera AFTER the power is off! How cool is that?

I'm running the camera from a dual port USB adapter that is running a Mobius (super-capped) in the rear and the GT680W up front. One port is 1 Amp while the other is 2.1 Amps. I consistently get the same ten second shut down from either the 1 Amp or 2.1 Amp port.

When on the first place you pulled out and dashcam shut down instantly is because maybe capacitors did not charged up in full ? Later on as you said it holds 8sec and only then shuts down, - now suparcaps getting fully charged and holding a power to be able to record 8-10 sec. Most important that they will not drain completely in order not to reset time and other settings.

How about start-up time now when it's with supercaps vs when it was with battery ?
 
When on the first place you pulled out and dashcam shut down instantly is because maybe capacitors did not charged up in full ? Later on as you said it holds 8sec and only then shuts down, - now suparcaps getting fully charged and holding a power to be able to record 8-10 sec. Most important that they will not drain completely in order not to reset time and other settings.

How about start-up time now when it's with supercaps vs when it was with battery ?

Well, on the USB adapter in my house I would leave it charging and the camera running for relatively long periods of time and it didn't make too much of a difference. It was really only the first time I powered up the capacitors and only charged them for one or two minutes that I had any issues with them apparently not being charged all the way. Since my earlier post I've done a little research and some people claim that capacitors require a break-in period and will perform better with more use. I don't know if this is true or not but it is a possible explanation.

Start-up time seems the same as with the battery. I see no difference. BTW, you may have noticed that I edited my original post from 8 seconds to 10 seconds. I went out to my truck with a stopwatch this time instead of just counting down and got slightly better results. Like you said, the main thing is to hold the time and date and to record the last file after power is withdrawn and so whatever the explanation is I'm very happy with the mod.

If anyone reading this post has any more information about capacitor break-in, I'd love to learn more about it. It is not clear if it is a real phenomenon or not.
 
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Well, on the USB adapter in my house I would leave it charging and the camera running for relatively long periods of time and it didn't make too much of a difference. It was really only the first time I powered up the capacitors and only charged it for one or two minutes that I had any issues with them apparently not being charged all the way. Since my earlier post I've done a little research and some people claim that capacitors require a break-in period and will perform better with more use. I don't know if this is true or not but it is a possible explanation.

Start-up time seems the same as with the battery. I see no difference. BTW, you may have noticed that I edited my original post from 8 seconds to 10 seconds. I went out to my truck with a stopwatch this time instead of just counting down and got slightly better results. Like you said, the main thing is to hold the time and to record after power is withdrawn and so whatever the explanation is I'm very happy with the mod.

If anyone reading this post has any more information about capacitor break-in, I'd love to learn more about it. It is not clear if it is a real phenomenon or not.

Usually if left dashcam with supercap for 1-2 horus, then it starts-up 4-5 sec ( @Panorama 2 ), but if left over night, then it takes 6-8 sec to recharge supercaps and another 3-4 sec to start up. Try to leave yours over night and measure difference in time start-up.
What do you mean under "capacitor brake-in" ?
 
Usually if left dashcam with supercap for 1-2 horus, then it starts-up 4-5 sec ( @Panorama 2 ), but if left over night, then it takes 6-8 sec to recharge supercaps and another 3-4 sec to start up. Try to leave yours over night and measure difference in time start-up.
What do you mean under "capacitor brake-in" ?

Capacitor "break-in" means that the capacitor will be able to hold more of a charge for longer periods of time after it has been used for awhile.

Edit: Some people claim this is true but it may only apply to certain types of capacitors. I don't know enough about it.
 
Capacitor "break-in" means that the capacitor will be able to hold more of a charge for longer periods of time after it has been used for awhile.

Edit: Some people claim this is true but it may only apply to certain types of capacitors. I don't know enough about it.

Same here, - still learning about them just like you: test'n'try ... some time maybe even "cry" ? if something goes wrong ... :)
 
Usually if left dashcam with supercap for 1-2 horus, then it starts-up 4-5 sec ( @Panorama 2 ), but if left over night, then it takes 6-8 sec to recharge supercaps and another 3-4 sec to start up. Try to leave yours over night and measure difference in time start-up.

I will see what happens when I start up my vehicle the next time.
 
Well, on the USB adapter in my house I would leave it charging and the camera running for relatively long periods of time and it didn't make too much of a difference. It was really only the first time I powered up the capacitors and only charged them for one or two minutes that I had any issues with them apparently not being charged all the way. Since my earlier post I've done a little research and some people claim that capacitors require a break-in period and will perform better with more use. I don't know if this is true or not but it is a possible explanation.

Start-up time seems the same as with the battery. I see no difference. BTW, you may have noticed that I edited my original post from 8 seconds to 10 seconds. I went out to my truck with a stopwatch this time instead of just counting down and got slightly better results. Like you said, the main thing is to hold the time and date and to record the last file after power is withdrawn and so whatever the explanation is I'm very happy with the mod.

If anyone reading this post has any more information about capacitor break-in, I'd love to learn more about it. It is not clear if it is a real phenomenon or not.
I believe the transformer in the supplied power cable has some power after you press the off switch on the cig. Plug.
Try it..plug cable in with no camera..press button to turn off. Now plug in camera, it will fire up
 
I believe the transformer in the supplied power cable has some power after you press the off switch on the cig. Plug.
Try it..plug cable in with no camera..press button to turn off. Now plug in camera, it will fire up

I'm not using the supplied transformer. I'm using a plain, shielded 28AWG USB to mini-B 5 pin USB cable. It works quite well. No problems with noise or GPS interference.
Yes, the supplied transformer has a capacitor that retains a charge but that's not the case here. The dual port 1 amp/2.1 amp adapter the GT680W is plugged into holds no charge. BTW, in my earlier post, I said, "I'm running the camera from a dual port USB adapter". I guess you missed that.

Edit: I use this set-up because I've been running both my front and rear cameras in "parking mode" using an external dual port USB Li-Po battery pack when I leave my vehicle parked somewhere. This works great and I love the capability.
 
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