Making a Video Out / OTG cable for Mobius Action cameras

Imagine my sadness when my brand new Mobius turned up the other day and I realized I'd forgotten to order a video out cable to use it with FPV. So I did the obvious thing, I made one and here's how I did it. 

1. Firstly you need to realize what an OTG (On the go) or video out (the same thing) cable is. Its simply a mini or micro USB cable with pins 4 and 5 connected. This is used like an internal switch to the device to alert it that in needs to send video out on the cable rather than act like a mass storage device or what ever else it does.  A normal USB cable the plus into your computer only has 4 pins in it so there will only be 4 wires going to the mini or micro end of the USB cable that we're going to be modifying. The 5th pin is the ground pin and is the one on the right as you look at the USB cable with the larger flat side facing down. You'll see what I mean in the pictures. So get you're self a Mobius to test your new cable with and get cracking. 

2. You'll need a mini USB cable. Just cut off how ever much you think you'll need.

3. Strip back the wires and pretin them with solder to be used later. Get that pesky shielding out of the way too.

4. Cut off the outer casing around the USB plug. Don't destroy it but rather cut a neat line down one side like this.

5. Remove the little metal housing around the plug by gently bending the side tabs outwards until the two pieces come apart.

6. Remove the bottom plate of the mental house not that it is separated from the top plate.

7. Now the hard part. You need to short out that black wire with the connection next to it. You can do this in two ways. Either you can solder it to the tiny little metalic stub on the back of the pin header where the wire comes out (like I did) or you can simply try adding a tiny bit of solder to the flat pins them selves (up at the base) to short them that way. I've done both and I would probably recommend the second way as its easier.

8. Check the connection with a multimeter to make sure that the pins 4 and 5 are indeed shorted out replace the metallic housing along with a little glue for strength. Epoxy works well for this. Make sure the pins that will go into the camera are flush up against the end of the housing (like it was before you took it apart).

9. Replace the plastic cover with a little more glue.

10.  A bit of heat shrink to hold it all together and job done. Now you can connect up you're video transmitter and give it a test. In the case of the mobius video out come out on pin 2 but don't forget to connect the ground pint as well to your vtx or you won't get any signal.

RC Man Child Store Review and Igniting an ESC

Recently I purchased some motors and ESCs from RC Manchild. I purchased the following gear. 

4x 400kv Motors

4x 30A HV ESCs

This was for a new quad I was building to be able to lift a Gopro and DYS 3-axis gimbal and hoefully be efficient enough to get decent air times with a 6S 4500mah battery configuration. 

It all went well until I flew it. You see I put 14x5.5 props on because that is what I'd seen someone on YouTube doing and figured that it would be perfect. However what I hadn't figured into the equation is that the YouTube video I saw was shot at 7000 feet elevation in the mountains of Utah. 

So when my quad took to the skies for the first time the result is seen below. 

The ESC literally caught first as it was drawing so much current.

Well I contacted RC Man child and got by far the very best customer service I've ever had. Not only did Don (the owner) reply to my emails incredibly promptly, but he helped me work out why it blew up, recommended some better props (these ones) and gave me a new one free of charge. Even though it was entirely my fault for destroying it. He even offered to give me a new motor if I'd managed to cook the existing one, which luckily I hadn't.

Very quickly he had the new ESC on its way along with some new props I purchased and they been working incredibly well even since. This quad gets 20+ minutes of the 6S 4500mah power pack while hauling around the GoPro and gimbal.

One more thing I'll mention from the RC Man child store is this little power distribution board. Its fantastic because not only does it provide and easy way to hook up your ECSs to the main power pack but it also provides a clean 12v output for running a gimbal and another clean output which you can vary depending on your needs. For example it could output 5v for power a second Rx for the person operating the gimbal in a two pilot setup.

Well the conclusion is a simple one. So far I've found RC Man child to be a fantastic company to deal with who sell a quality product and have awesome customer service. And finally make sure you look up what size props to put on your motor/ESC comb so you don't building a flying flame thrower like I did.

Battery Plugs: Deans Vs XT60

I've been a life long user of the Deans battery plugs but recently having been fed up with them I switched to the newer XT60 style.


Here's my thoughts on each of them.

Deans

Pros: Never going to unplug them selves. Very strong connection and can easily transport a lot of current with out heating up. They also have little grip lines on the side to make them easier to pull apart.

Cons: You'll need super human thumbs to take them apart. Because of this the solder on the terminals tends to get a lot of strain put on it and eventually crack. They are not the cleanest or easiest so solder either. The worst thing about them though, is that they are very hard to plug together and you end up with a bunch of arcs and sparks as you try to join them. Not really good for your batteries or the electronics you're powering up and down several times while you try to plug them in.

XT60

Pros: Very easy to plug together and don't cause current surges while you try and plug them in. Very secure and won't come apart on their own. Very easy to solder. Have little + and 1 symbols on them so you don't accidentally solder one backwards.  Hobbyking batteries come with these plugs on them. They are very cheap to buy packets of them.

Cons: Can be difficult to unplug but not no where near as bad as Deans.

Conclusion: Well its pretty clear from the pros and cons lists above that I have become a big fan of the XT60 plugs. I've used the Deans for a long time in all kinds of flying contraptions but I've become a very big fan of the XT60 in a very short time. The only downside is changing all the batteries and ESCs over, but as I quite enjoy soldering, that's not so bad. 

Battery Strap Reviews

It seems to me that there are two main types of battery strap out there for purchase. There is the name brand ones like Turnigy and DJI and then there's the generic ones from places like HobbyKing. Well here's my point form review of each of them two main types.

First up we have the more expensive name brand straps like this Turnigy. Turnigy claim that these provide better grip and don't turn to fluff eventually after a lot of use. Well that might be the case however I've found that they are also very hard to use. Sure they have a nice grippy surface but they are much much harder to tighten. I want my battery straps to really hold things and these ones just don't do that very well. You can't pull the strap back on its self to tighten it so you end up just having to tighten it as much as you can and hope it holds. Also because the hook and loop stuff (it's not Velcro because that's a brand name) is finer you kind of get the feeling that it wouldn't take much to pull it off at the right angle.

Now compare the above findings to this strap. Its from HobbyKing and has no brand at all. That's really saying something considering some of the things they have branded there. Its also less than half the price of the name brand straps. However its got this brilliant little plastic loop which allows you to tighten the strap back on its self and make it as tight as you want. Also the hook and loop stuff really grips. I can see that over a very long period of time it might look some of its holding power but realistically at eighty cents each I'd rather replace them and have the ease of use and peace of mind knowing my batteries aren't going to fall off midair coz lets face it, that's very bad.