XT30 Battery Discharger

The other day I was charging up some batteries to fly and was surprised when a ground lead snapped off of its XT300 connector when I was pulled it off of the charger. That’s bad because one it couldn’t fly it and two I’d just finished charging it up so the battery was at it’s most dangerous.

I checked the rest of the batteries and noticed that there was one other one where the ground lead wasn’t stiff at the XT30 connector like it should have been. It hadn’t come loose yet, but I figured it would soon. I left it alone at this stage though so I could fly it and run the battery down.

I joked online about resoldering the connections, but I never seriously contemplated doing that. I’ve soldered a lot of XT30 connectors but never where the wires were attached to a battery. It’s possible to do, but you have to be careful about getting the wire too hot and damaging the battery’s wiring connecting the cells together or worse damaging the actual cells and potentially causing one or more to fail. Batteries are cheap enough that I’d rather just replace one than risk causing a fire trying to repair one, especially one that I’d been flying for months and pretty much had gotten my money’s worth on anyway.

It did make me realize a bad habit I’d picked up though. I’ve gotten pretty used to using the leads to disconnect XT30’s either from the quadcopter or from charging boards. I don’t know for sure that my habit was the sole cause for those two battery leads breaking, but it’s likely that it contributed. I have four more from that set that are all fine, but I’ve still tried to be better about using the plastic housing on the XT30 and the balance plugs to disconnect rather than grabbing the wires.

Disposing of batteries requires discharging them down to zero, and that’s a bit of a trick as most battery chargers that have a discharge setting won’t go below 3.2 volts as that’s usually the absolute minimum before damage will occur to the battery. So while I could discharge both batteries down to 3.2 volts, I couldn’t get them to zero and so safe to take to recycling without making something.

There are a few different ways to completely discharge a battery that carry varying amounts of danger with them from the completely safe and very slow saltwater bath to the very dangerous and not smart puncturing the cells with a nail. I opted to a fairly safe and fast method of using light bulbs. The only danger here is the heat that the bulbs generate while discharging, but that’s easily managed by hanging it off of the edge of my desk.

One thing I didn’t want to do though was just solder a bulb to an XT30 connector and leave it at that since eventually the bulb would need to be replaced, even if it would probably take a long time for that to happen. I found a set of bulb sockets on Amazon that looked like they would work pretty well along with some Halogen bulbs.

After that it was just a matter of soldering an XT30 connector that I could plug batteries into and soldering that to one of the bulb sockets, which I decided to shorten as much as possible to limit the amount of current traveling through those thinner wires.

Once I had it soldered and heat shrink over the connections I was able to test it out on the battery where the ground lead hadn’t quite come loose yet. I tried to keep a battery tester on it but since I’d flown that battery after charging it, it was already down to about 3.5 volts and once it went below 3.2 volts there wasn’t enough juice for the tester to run.

The other battery required a little extra effort to discharge. My multimeter came with a set of cables, one red and one black, that had alligator clips on the ends, and I was able to use one of those to connect the ground lead to the XT30 connector. That seemed much safer to me than trying to hold the wire against the connector with a pair of pliers. Thankfully it didn’t take long for the halogen bulb to kill the battery, but it did produce a pretty impressive amount of heat. I could feel it just by holding my hand over the bulb, and I’m sure it was hot enough that I would have gotten a nice blister if I’d have touched it. It did cool off afterwards quite quickly though.

After killing both batteries I cut the leads and balance plugs. The trick with this is not to cut both wires at once which would short them out. It shouldn’t matter since I’d discharged both batteries down to where the bulb wouldn’t light but that didn’t necessarily mean they were at zero volts, it was just too little voltage to light the bulb. It’s just a good habit to havy anyway.

I gut the red wire short since the black ones were both snapped off at the lead. That way the wires can’t come into accidental contact like they might if their lengths were similar. Then I taped all of the wires to the battery just to make sure that nothing could come in contact with the wire ends. It’s probably overkill, especially for a relatively small 2S battery, but I’d prefer to err on the side of caution.

Discharged and taped up, I put them aside for the next time I’m near the battery recycling center for disposal.

XT30 Switch

When troubleshooting a quad problem or when getting a new build configured, I’m regularly plugging in a battery to a quad to power the motors, VTX, and receiver, and then unplugging it again. I don’t like to leave the battery plugged in any longer than necessary since the VTX can quickly overheat and damage itself. They’re designed with the expectation that the quad will be moving and getting a lot of airflow to cool off. Even with the VTX set to it’s lowest power of 25 mW, I’d still just prefer not to leave it powered any longer than necessary.

So that means dozens of cycles of plugging in an XT30 connector and then unplugging it again, which quickly becomes tedious and hard on the finger tips.

With my HD toothpick build coming up I was thinking about this, and realized I could get an in-line switch and add XT30 connectors to either end as a way to easily switch the battery on and off. Even better since that could also plug into my smoke stopper as well.

I did a little research on Amazon and settled on these inline 250V 10A appliance switches. I would never be drawing anywhere near 10 amps while powering a quad on my bench, so it seemed more heavy duty than I’d need but I always like to be extra safe when dealing with electricity. When they showed up I was pretty happy with the quality of the housing and the hardware inside.

Making the switch was pretty easy, there was no soldering to do for the switch itself, I just had to make the XT30 male and female ends, which is a very easy soldering project. I cut some 14AWG silicone wire to what I thought was a decent length and laid out those with some heat shrink, the switch, and the XT30’s just to try to get everything straight in my head and make sure I’d thought it all through.

Soldering the XT30 connectors only took a few minutes to do, and I also went ahead and tinned the wire ends that were going into the switch just to make sure that the wires were as durable as possible.

Then it was just a matter of connecting the wires inside the switch keeping the positive and negatives lined up correctly. Except I found on my first test that plugging in the battery, the switch was live in the off position and the led light wasn’t working. I had to take it apart and swap the sides for the male and female connectors.

For the second test the switch worked as expected except that the LED wouldn’t come on. I tried a different switch with the same issue. So I’m not sure if the LED’s are just set for a higher voltage like you’d get from a house line or maybe it’s an AC versus DC thing, but the switch part worked like a charm which was the important part for me.

For such a simple and easy project, I think it’s going to make a world of difference the next time I’m trying to bind a receiver and I have to press a tiny receiver button with a pair of tweezers while simultaneously plugging in a battery. Something which really requires an extra person to do without swearing, and now should be pretty easy to do with just two hands.

Brushless Whoop Build – Part Two

Last time I left off at having finished the soldering and successfully tested that I could connect with my radio to the flight controller and receive a video signal on my goggles, and that the video signal was right side up. I tested that the VTX protocol was configured correctly so I could use my radio to bring up the VTX settings in the OSD on my goggles and change the VTX band and channel, and that the frequency the VTX was transmitting at changed appropriately.

Everything worked as expected, so aside from the one solder bridge issue that I had to fix the first part of the build was pretty trouble free. At this point I figured that the hard parts were done as the rest of the work was just assembling the pieces onto the frame, which normally isn’t any harder than building a Lego set.

First step is to put the rubber mounting grommets on the corners of the flight controller and then mount it in the whoop frame. The grommets are hollow and fit over plastic posts that have threaded screw holes in them. I put the screw in at the rear of the flight controller as that one wouldn’t be covered by the camera mount, and it left me get the flight controller partially secured into the frame.

The next step was to get the camera snapped into its mount and then fit that over the two side and front grommets of the frame, and get all three remaining screws in and snugged down. One of the major bad habits that I’ve had to overcome with building quads is over tightening screws. Especially in instances like this where doing so flattens out the grommets and cancels out any vibration protection that they might provide for the flight controller. Or worse stripping out the plastic posts so that the screws don’t hold at all.

Once I got the camera mounted, it was time to get the VTX on. I’d tried a couple different options before starting the build and I thought I’d figured the best way to get the VTX and antenna mounted. I started by cutting some clear heat shrink to keep the VTX from touching the back of the camera and shorting out. It also had the added benefit of holding the antenna in place so I didn’t have to worry about trying to secure that as well. With the heat shrink on then I zip tied it upright to the back of the camera mount with the status LED and button visible.

With all of that out of the way, all that was left was the motors and props. After doing the first motor, I discovered it was easier to plug them into the flight controller before screwing them into the frame. So that’s how I did motors two through four.

Putting the props on requires some attention to detail since props come in two versions clockwise and counter-clockwise, and they have to be put on in a certain order. For my setup, I prefer what’s known as reversed props or props-out. Which means that the front right and rear left props spin clockwise, and the other two counter-clockwise. There’s some aerodynamic benefits to setting up the props this way, Oscar Liang has a good article on that.

Usually I don’t have any problems figuring which prop is which and getting them all on the correct motors, but I ran into a novel problem with the new Azi props I was using. I got one of the motors put on upside down and didn’t realize it until all four props were on. I’d never had a problem with putting a prop on upside down before. To make things worse, these were push fit and didn’t need or use screws. Which meant they were extra hard to get back off in order to fix them.

In the end because the whoop frame was pretty flexible and the props were on so tightly, I ended up having to unmount the motors so I could get a good enough grip on them to pry off the props and get everything back on right-side up and in the correct order.

The last step was to hook the quad back up to my computer and launch the BLHeli utility to make sure that all four motors were spinning the correct direction. In this instance motors two and three were backwards, but it’s an easy software change to make and write to the ESC’s. Once that was done the build was finished.

All together the new whoop weighs 24 grams and 32 grams with a 350 mAh battery, that’s just 2 grams more than my brushed Acrobee.

The last step naturally is to fly it. I charged a couple of batteries up and plugged the first one in to do the maiden flight and ran into an issue where only three of the motors spun up after the quad was armed. I tried disarming and then arming again and all four spun up but not all at once. This is odd as I’ve always had all of the motors spun up at the same time.

At first I thought I might have a power issue or some bad motors or ESC’s or something. But I found that when I connected the quad to my computer and tested the motors individually they all spun up fine. It only seemed to be a problem when I armed the quad and all four would try to start at once. I looked online but wasn’t finding any good results, not until I thought to go to BetaFPV’s site for the motors I was using. There was a link there to a support page that covered the issue I was having, which led me to looking at the startup power setting in BLHeli.

This being the first quad I’d built or used with the combination of brushless motors and 1S voltage, it had never occured to me to think about the initial amp draw that happens when the quad is armed. But it made sense once I read through the page, since the motors were fine when tested individually, and sometimes when arming I’d get a couple of motors to spin up initially and then another one or two a moment later. I ended up increasing the startup power for all four motors to 1.5 going in 0.25 increments until I could consistently get all four motors to spin up simultaneously when arming the quad.

Altogether it took me about 28 minutes to do the initial soldering, another 11 minutes to fix that solder bridge, and nearly 50 minutes to do the assembly including having to redo the motors and props and figure out the motor power issue. So the whole process was about 90 minutes, which isn’t too bad.

I’ve flown a few dozen batteries on the whoop since then and it’s quite a bit of fun to fly inside. It’s just on the edge of being too much power for indoors at least in my home which doesn’t have a lot of open space to fly. I think when I take it to the local fly-in office space it will be a lot more fun than my old brushed quad.

I also tried it outside just recently when there was some good weather and it did okay, but it’s not nearly as much fun as my toothpick is, and I only did two batteries outside out of curiosity. I think most of the time that I can fly outside it’ll be my bigger quads.

Brushless Whoop Build – Part One

It took me a while to actually sit down and do the build for the brushless whoop parts that I got for Christmas.

The first thing I like to do on a new build is test the flight controller. Especially before any soldering is done, it’s good to make sure that the flight controller works, so that later on if it doesn’t I know that it’s because of something that I did and can troubleshoot it instead of wondering if I just got a bad one from the factory. It’s easy enough to do. Plug it into a USB cable to make sure it gets power, and then make sure that Betaflight will connect to it. Test out the gyro by turning and tilting the board and make sure that the movements match up with the animated diagram in Betaflight.

At that stage, it’s not critical to do, but since it’s already connected, I like to download the latest firmware and flash it to the board. It’s just a couple of steps to do, and isn’t any harder or easier to do now or wait until later. But since it’s already connected I figure why not.

The last step I took care of before really starting the build was binding my radio. I don’t always do this part so early, usually because for anything bigger than a whoop build, I don’t use a flight controller with a built-in receiver. So there’s some soldering that normally has to take place first. But in this case since the receiver is built into the board, it’s much easier to do now where the bind button is easier to get to, than to wait and do later.

Binding the radio took me a bit to figure out since I had to find the built-in receiver specifications. I couldn’t find anything about telemetry being available or not, but it would only successfully bind when I picked the radio setting without telemetry, so I’m guessing it’s not supported. Not a big deal for a small whoop like this, but something I’ll have to keep in mind if I ever decide I need to go hunting for it outside.

With the flight controller testing out of the way, I was ready to start figuring out the build. This involves dry fitting the flight controller to the whoop frame and trying to get an idea for where the canopy, camera, and VTX were all going to sit. I found the wiring diagrams for the flight controller on BetaFPV’s site, and used those along with the printed manual that came with the VTX to figure out how everything needed to be wired together.

The only part that wasn’t immediately obvious to me until I’d studied it for a couple of minutes was that the signal wire of the camera needed to go to the camera pad on the flight controller. This would apply the OSD information, and then a wire from the VTX pad to the video in pad on the VTX would take the signal for broadcast. I also didn’t need one pair of the 5V and ground wires on the VTX since the camera already had its own.

Once I figured all of that out, then I rechecked it by fitting all of the pieces together to make sure I knew which wires to cut, which to desoldering, and what was getting soldered to what. I could always fix any mistakes, replacing or lengthening any wires that I cut too short, but I didn’t want to have to mess with that if I could avoid it with a little extra care up front.

After checking a few times though, it’s usually time to just commit and do it and hope I’ve thought through everything I needed to. In this instance that included trimming all of the VTX wires to be just a bit longer than the camera wire lengths. Trimming the plug from the camera, which I wouldn’t need, and then desoldering the two wires from the VTX that I wasn’t going to need.

Desoldering is quite easy. It just requires me to get the piece set up where I can get some pressure on the wire that I’m trying to remove, so that I can have a minimal amount of time for the soldering iron on the board. In this case the extra 5V and ground wires that were going to be replaced by the corresponding wires on the camera.

After getting the wires cut to length, I was ready to tin the wires and the pads on the VTX and flight controller. Tinning just means to prep exposed wires and any copper pads on PCB’s that I’m going to be using with solder. Ideally so that when it comes time to solder a wire to a pad, I don’t have to add any additional solder, I can simple touch them together with a bit of heat and I’m done.

Soldering a small build like this is a bit of a challenge just because of the sizes of the pads involved. I’ve found using the lowest heat setting along with a lighted magnifying glass, and a very small soldering iron tip helps tremendously for this. I’ve also applied some tricks I picked up in painting miniatures for keeping my hands steady by moving the piece to the iron and keeping my arms are my sides.

Once everything has been tinned and then soldered together, the easy part is over. With the camera, VTX, and flight controller all wired up, it’s time to check for shorts and then plugin in a battery.

Before plugging in a battery and risking releasing the magic smoke, I like to use a multimeter and check that there’s no continuity between the various connections. For example the yellow wire from the VTX to the flight controller should have continuity between the ends, but if I touch a probe to one end and then touch the other probe to the ground then I shouldn’t have any connection. If I do it means there’s a short somewhere, and on a tiny build like this it’s probably because two pads are bridged.

In my case I did have a solder bridge on the VTX between the video signal and the ground. But that’s just a matter of adding some flux to the board and using a soldering iron to try to clean up the bridge. It only took me a couple of minutes to get it cleaned up in this case, and afterwards all of the connections passed the multimeter test.

Which brings me to the last part before assembly and that was plugging in a battery and testing that everything booted up, that the VTX was broadcasting, and best of all that I was getting an image through the goggles from the camera. It’s good to do all of that before assembling everything just to make sure that there’s no more soldering fixes that need to be made, and it’s a good chance to make sure I know which way the camera needs to go so that up is up.

Building a Quad – Frame Change

After my first real flights ended with a broken battery lead and a fried flight controller and messed up video transmitter, I decided that since I was going to have to take everything apart anyway, I might as well change the frame I was using. While I liked the Phreak it really wasn’t suited well to having a four high stack, and rather than getting taller standoffs and screws to raise the top plate I decided to switch to an Acrobrat.

An Acrobrat is a 3″ frame designed with three mounting positions and a top-mounted battery, where the Phreak only had one mounting position and a bottom-mounted battery. That meant I could separate out the boards in the flight stack and have the camera and HD board up front, the flight controller and ESC in the middle, and the VTX and receiver in the back. Having the battery on top also meant I wouldn’t be landing on it.

Since I was moving to a new frame, I also got a new set of 3d printed accessories from Brain3d. They had a nice kit that included arm guards, front bumpers, and a nice rear mount to handle both the VTX and receiver antennas.

Of course switching the frames meant taking everything off of the original and moving it over to the new one. But more than that, I had to lengthen the motor wires since the Acrobrat’s layout had a wider length from where the motors mounted to the ESC on the center stack. Fortunately I had saved all of the wire I’d originally trimmed, so it wasn’t too difficult to solder and heat shrink extensions on and retrim and solder back onto the ESC. I also decided to add a capacitor to the build to help smooth out any electrical noise, and taped it down to one of the arms.

With that done I was back to the original repairs I would have needed anyway. I soldered the wiring harnesses back up to the new flight controller board and reseated it on top of the ESC. Then I got the camera and VTX both hooked back up and mounted. The receiver I ended up loosely zip tying to the VTX, which I’m not sure was a good idea even with the Kapton tape to keep them electrically isolated but I haven’t tried changing that around yet.

While it didn’t take me as long as the original build it was still a few hours worth of work to move all of the electronics over to the new frame. I have to say that it was worth it though. It was much easier to fit everything in the Acrobrat than it was the Phreak, which just wasn’t designed to have that extra board in it for HD capture from the FPV camera.

Battery leads securely zip tied to the side-plate of the frame.

It took me a while to get to this point, but I’m pretty happy with the second iteration of my 3″ quad build. I have to put a 60% throttle cut on it in order to fly it around my yard, but that power is nice to have when I go to my in-laws farm or take it to a nearby park.

Building a Quad – First Flights and a Mistake

Can you spot the problem?

Having finished building my first quadcopter, I took it outside for a hover test and maiden flight.

For the hover test, I basically treated it like a live grenade. Setting the quad up on the driveway, gingerly plugging in the battery, and then sprinting away. Which is comical looking back on it now, but at the time I really had no idea what to expect. Before then I had already done motor tests without the props on, but something about having three inch spinning plastic blades had me erring on the side of caution. I armed the quad and throttled up until the quad lifted off of the ground and then I held it there for a few seconds before setting it back down. It didn’t flip out or anything, so it was time to actually fly it.

With my goggles on, I rearmed the quad and took it for a short maiden flight around my front yard. It was exhilarating but terrifying as well. At the time I just assumed it was because I was going from a small quad with brushed motors to a bigger one with brushless motors, and that I would get used to it after a period of adjustment. Regardless the maiden flight was good, although I didn’t really get a chance to push the motors much. I had wrapped up my build late and was pushing sunset as it was. I didn’t think it would be smart to take risks with a brand new quad especially when I wasn’t comfortable yet with the new size and additional power.

That weekend, we had a trip up to my in-laws farm for the weekend, which excited me since I’d have the chance to fly someplace where I wouldn’t have to worry about space or people or traffic. Although I did realize shortly after take off that I hadn’t paid attention to where the overhead power lines were, so I had to land and take my goggles off briefly to look around and map out what areas I wanted to stay away from. I had six batteries charged that I was looking forward to using.

The first flight went pretty well, and I was enjoying really getting to go full throttle with it. I was still pretty terrified of crashing it before I’d really gotten a chance to enjoy it much, so I was playing it safe and not trying out any rolls or flips or dives. But it was still a lot of fun to race over the fields and along the fences.

The second flight was great too. I was starting to relax a bit more, although not enough to start trying any tricks. It was really enough of a learning experience to adjust to the bigger weight and different type of motors, than to worry about doing any fancy flying.

Sadly there wasn’t a third flight.

I don’t know if it was the way I unplugged the battery after the second flight, or if it was a bad solder joint that was weakened by the vibrations during flight. But the red wire on the battery lead had come loose from positive battery pad and I didn’t realize it until I plugged the third battery in and I heard a popping noise. At first I didn’t realize what had happened so I unplugged the battery and plugged it back in again. Which is when I noticed that the red wire was loose from the pad, and quickly yanked the batter again.

I hadn’t release any magic smoke, and there was no visible damage to any of the electronics. I figured the electronics were fine and I would only needed to resolder the lead back onto the pad in order to have the quad working again. Of course it turned out to be a bit more of a struggle than that.

Once I got home, I resoldered the wire and plugged in the quad, but nothing happened. I then tried plugging it into USB and still couldn’t get any life from the flight controller. Despite there being no visible damage to the flight controller there was a short in the board somewhere. It turned out that while the ESC board was fine both the flight controller and the VTX were shot and had to be replaced. It was a $60 reminder about something I’d forgotten to do when building the quad, zip tie my battery leads.

In all of the buld videos I’ve seen the person doing the build always zip ties the leads to the frame after getting them soldered. This is incase the battery gets ejected in a crash that it won’t rip the pads right off the the board. Or in my case so that the joint isn’t getting pulled on. Even if it had been a bad solder join, had I zip tied the wires in place then it wouldn’t been moving around and possibly not even ruined any of the electronics.

Going back and looking at pictures from the original build, I actually think the ground wire joint looks worse than the positive does. The other thing I should have done better here was solder the wires at an angle so they were coming out along an arm without any sharp bending.

Building a Quad – Assembly

After picking the parts the first thing I did was take the flight controller and plug it into USB and connect it to Betaflight to check two things. First just to make sure that it powered up before I started doing any soldering on it. So in case I got a defective part I would be sure that it wasn’t something I did on the workbench that broke it, and I’d more easily be able to get a replacement. The second thing was to see if it was to record the firmware target that the flight controller was using and make sure it was the most recent firmware version.

Then next thing to do to prepare for the build was to flash the receiver with the most recent firmware version from FrSky. This was a new process to me and involved downloading the firmware from the vendor, storing it on an SD card that I inserted into my radio, and then plugging the receiver into the radio using a wiring harness that the receiver came, then flashing the firmware.

Finally it was time to start building the quad, starting with the frame. I’d already watched a video of a more experience builder putting one together, but seeing it done once and doing it yourself tend to be very different experiences. For fun and to try to stay organized, I started out by organizing all of the pieces.

There’s four arms, blue standoffs, a top plate, a pair of bottom plates that sandwich the arms, and miscellaneous screws. Putting it together wasn’t too much different from assembling a Lego kit or any of the various children’s toys that I’ve had to put together after a birthday party or on Christmas morning. I think it took me about 20 minutes to get the bottom plate and arms assembled and be ready to starting on installing the motors and the electronics.

Before I started installing any of the electronics, I needed to tin all of the pads, and I figured that would be easier to do before I put them on the frame. In all of the build videos I’d watched to get ready for this, the builder would just put the board on the frame and then add the solder from there, but I was coming into this with just a little bit of soldering experience and I wanted to give myself the best chance at success. So I laid out all of the boards in the flight stack and made sure I knew which wires ran to which pad.

Then I tinned all of the boards at once: flight controller, four-in-one ESC, and VTX. The Caddx HD capture board on the camera had plugs and didn’t need any soldering.

Putting the ESC onto the frame as the base of the flight stack and installing the motors marked the first real part of the build for me as the quadcopter started to take shape. The process itself was pretty simple: screw a motor onto an arm, run the motor wires to the ESC, measure and cut the wires, solder them to the ESC. But cutting wires like that was a bit nerve wracking for me, as I was paranoid about cutting the wires too short and too long. On the one side I’d end up without enough slack and have to solder additional wire back on along with heat shrinking the joint, and on the other side I was trying to have a clean build plus extra wire would also contribute to extra weight. Which a few grams doesn’t sound like a lot but for a small 3″ build like this every gram counts.

After that the next step was the battery lead. As often seems to happen to me with this hobby, the part I was thinking was going to be easy turned out to be pretty difficult. It took a lot of work for me to get these two leads soldered onto the main battery pads of the ESC board. The heavy gauge wire and the big soldering pads on the board required a lot more heat than I’d been using up until now in order to get the joints flowed together properly.

Soldering the rest of the electronics was pretty easy. The hard part had been getting the documentation online for the various parts and making sure I knew which pads to use on the flight controller for the camera and the VTX. It had a pin header that plugged straight into the ESC board which made assembling the rest of the flight stack pretty easy.

Then came the big moment, plugging in the battery for the first time to see if it all worked. After going over all of the solder joints with a multimeter to see if I had shorted anything, I took the battery and plugged into a smoke stopper before plugging that into the battery lead on my new quadcopter. A smoke stopper is basically a fuse that will trip in the case when there’s a short somewhere so that you don’t release the magic smoke from the electronics. I’d bought one with a light and a reusable fuse at the same time that I ordered my parts.

The smoke stopper lit up green and the leds on the flight controller, receiver, and VTX are lit up as well. The best part though was hearing the startup tones playing as the flight controller and motors synced up.

After the battery test I connected it to my computer and went into Betaflight to check that all of the motors were spinning the right direction, and then change the settings on the two that weren’t. Then I plugged in a battery again and I checked that my radio would connect, and that I was getting a video signal in my goggles from the VTX.

At this point I figured I was just about done, I just needed to put the top plate on and the props. Which naturally is when I ran into the one problem that gave me the most trouble in the whole build.

When I picked out all of the parts, I remember adding up all of the heights to make sure that it would fit inside the frame. But I was looking at the height of the standoffs on the frame and not the length of the screws for the flight stack which were a couple of millimeters shorter. That makes sense to me now since you don’t want those touching the top plate and transferring impacts from the top plate into the flight stack, but it meant that I was just a couple of millimeters short on getting the top plate on my brand new build.

It took more time rearranging the parts and trying difference spacers between the boards to get everything to fit than it did to do the whole rest of the build, or at least that’s what it felt like to me, but in the end I did manage to squeeze everything in. I wasn’t completely happy with the solution but it would do until I could order slightly taller standoffs and longer stack screws.

Building a Quad – Picking the Parts

With the weather warming up I started looking into building a larger sized quad to fly outside. I decided I didn’t want to go straight to a full sized quadcopter with 5″ props which is the standard for FPV freestyle. I wanted to be able to fly comfortably in my yard, so that I could get more time in during the week, rather than always having to go to a field or park. So I settled on a 3″ build plan, because I’d heard that building for smaller props than that wasn’t as good of an experience.

Build a quad from scratch was a daunting experience because of all of the different pieces that needed to be selected and work together. You have to decide on a frame, what size of motors, the camera, the video transmitter (VTX), the receiver, the antennas, the props, the electronic speed controllers (ESCs), and the flight controller. Each component has an impact on the others too. There’s the obvious factor of the weight of the different components versus the thrust that the motors and props will generate, but also just compatibility between the amount of space in the frame for components and the mounting pattern versus the size of the flight controller and other electronics.

I started with the motors and got some advice from some local pilots to look at 1407’s as a good size for flying 3″ props. Then I used a site called RotorBuilds to figure out the rest of the parts list. It’s a site where people post their quadcopter builds. Some with detailed articles and photo albums of the step-by-step and others with just a short description of how it flies. But all of them have a parts list with links to vendors on them. So I ended up searching the site by the size of motors I was looking at building with and getting ideas from that on what parts I was going to buy. One build in particular I ended up being interested in was a 3″ Xilo Phreak because the guy mentioned how durable it was, and I figured as someone just starting out that getting a quad that could handle some hard crashes would be a good idea. I also liked that the Phreak frame had replaceable arms, so I figured in a worse case scenario if I crashed and broke one I wouldn’t have to rebuild the whole baseplate.

For the flight controller, I ended up going with the one mentioned in that RotorBuilds parts list. The HGLRC stack came as a combo with a four-in-one ESC and a VTX so I didn’t have to worry about them working together and the price on the full stack was just a little cheaper than what I’d have spent on separate boards.

When looking at cameras, the major factor in picking one was that I wanted to do HD capture from this quad, and a 3″ build though is too small to carry a GoPro. Plus there was the fact that I didn’t own a GoPro and I didn’t feel like spending a couple hundred dollars to get one. So I had only two choices: a RunCam Split or a Caddx Turtle. Both of these are camera and HD capture board pairs where the camera signal passes through the board first for recording, then goes to the flight controller to get the onscreen display overlay, and lastly goes to the VTX. This allows capturing HD quality video to an SD card on the quad without any analog transmission, but adds some latency to the signal. Latency is a big point of contention among pilots. It is the amount of lag between the camera on the quad capturing an image and that image showing in the pilot’s goggles. Some people seem to be able to notice and be bothered by tiny amounts of latency in that setup, and try to stay away from these types of split capture boards. I’ve never really noticed a problem with it though. I picked the Caddx because it came in black and was a slightly newer design.

The receiver and antennas were that last parts and those were pretty much a given. Since my radio uses the FrSky protocol, and I wanted telemetry on the quad, I only had one option in the R-XSR. For the antennas I had an omni and patch Axii on my goggles already so I got another omni with the same polarization for the quad build.

I was doing all of this near Easter so many of the sites were running sales. I ended up getting most of the parts from GetFpv.com. They didn’t have the receiver in stock though, so I ordered that plus a couple of batteries and a smoke stopper from RaceDayQuads.com. Then I just had to wait for everything to show up.

Here’s the final parts list:

The Jump to 64-Bits

In addition to my recent computer hardware upgrade, I also upgraded the OS jumping from Windows XP to Windows 7 RC and from 32 to 64 bits.

I’ve been a Windows XP user for a long time now, and I had no inclination to go to Vista.  The only compromise I’d made was adding some programs like Launchy to incorporate similar Vista-like UI improvements into my XP experience.  When the Windows 7 RC came out with so many rave reviews, I decided to try it out on my secondary desktop.  I have been very happy with it, and had no trouble with finding drivers for all of my existing hardware or running any of my software.

Unfortunately I wasn’t able to pre-test going to 64-bits, so that was the big test on the new machine.  Fortunately, I’ve had nearly no problems.  Of course, my video card was brand new so that was an easy update from Nvidia’s site.  My printers, an old HP LaserJet 5p that I’ve had for over 10 years and an Epson Stylus Photo 820, both loaded drivers with minimal hassle.  The Epson pulled drivers from Windows update, but the LaserJet required me to grab the Universal PCL 5 drivers from the HP site.  My monitor, keyboard, mouse, game pad, DVD-ROM, and DVD-RW all loaded with no problems.  The only issue was with my Epson Precision 1650 scanner, which I was able to get working in 32-bit Windows 7 but didn’t have support for 64-bit.

I was pretty worried, based on past horror stories of moving to 64-bit Windows, both Vista and previous.  Overall though the jump to 64-bit has been painless and is definitely worth the performance gains of getting access to 6GB of RAM.  The only downside to upgrading to Windows 7 so early is that I’ll need to reinstall once the retail version is released, but I have until (I think) June next year to do it so I’m looking at it as an enforced spring cleaning for my operating systems.

Computer Upgrade

I have been wanting to upgrade my gaming PC for quite a while now.  I used to build a new machine every 3-4 years.  Each time I would try to by the latest and greatest parts and I usually managed to skip a CPU generation each time.  My current PC has been near it’s end of life for quite a while now:

  • Intel Pentium 4 3.2 Ghz
  • 4gb of RAM
  • Windows XP 32-bit
  • ATI Radeon x1950 Pro AGP

I had upgraded the memory and video card  over that last two years in an effort to delay the big upgrade.  The biggest problem was the motherboard predated PCI-E so I couldn’t upgrade to any of the current drop of high-end video cards.  And a motherboard upgrade meant that the CPU and memory both had to be upgraded.  Which all adds up to money.

It used to be that wasn’t a problem, I was single and had a well paying job, so I had quite a bit of disposable income.  Now five years later, I’m married (and my wife is not a gamer) and I have a 10 month old son, so money for upgrading a computer is not high on the priority list.  So over the last year I’d been putting a bit aside each money with the goal of building a new machine.

I hadn’t planned on building a new machine for another two months or so, but two things put me over the edge.  First, Crazy Kinux built a new machine and I started feeling like the last gamer on the planet still using a Pentium 4.  Second, I started playing the Champions Online beta and I had to turn down so many settings to get it to play smoothly that I realized I was finally too far behind the curve.

So I took gave myself a budget of $1400 and started shopping online.  After checking my back issues of PC Gamer and Maximum PC and reading some reviews online I here’s the parts list I settled on:

  • Intel i7 920
  • Asus P6T
  • 6gb RAM DDR3
  • Cooler Master Storm Sniper case
  • Silent Pro M 700W Power Supply
  • Cooler Master Hyper N520
  • EVGA GeForce GTX275
  • Seagate 3.5″ Barracuda 1.5TB SATA drive

I decided to use the on-board sound and networking, and I already have a good monitor (Dell 1907FP), keyboard and mouse.  All in all, not an extreme high-end machine, but not a budget box either.

Fry's Shopping

I intended to buy the case locally and order everything else online.  So I headed to the Fry’s here in Indianapolis to pick up the case and see how they compared on the other parts.  Turned out that Fry’s prices were as good as most of the online prices (without even accounting for shipping), so I ended up buying everything that day.  The final total was $50 bucks under my budget, and that’s not counting rebates.

I also cheated a bit by paying the service department to install the CPU and fan on the motherboard for me.  I hate working with thermal paste and after seeing the directions involved on installing the fan, I decided that was the best $10 I’ve ever spent.

Here’s a few shots of all the beautiful boxes (click to enlarge).

Case and Motherboard

CPU, PSU, Fan and Drive

GPU

Motherboard with CPU

After I unboxed the case and started to install the mounting screws, I ran into my first problem.  There was no IO shield in the parts bag from the motherboard.  I made a quick call to Fry’s and was told I would probably have to return the motherboard, which meant removing the CPI and fan.  I was not happy about the situation as I drove back to Fry’s, but when I got there customer service allowed me to take an IO shield from another box already setup for a return.  So at least I had a quick resolution and a happier drive home.

IO Shield
Lot of trouble for such a small part.

Fortunately the rest of the build went pretty smoothly.  The Cooler Master case was a joy to build in, completely tool-less for everything except mounting the mother board and some really nice, large fans.  It also has a nice set of USB and audio jacks on top along with a power button and a fan control.  It also has a set of blue LED’s in each of the fans and there’s a button on the fan control to turn them on and off.

img2009-08-29-16.47.12
Geek's version of Black Beauty

img2009-08-29-16.48.32
Completely tool-free for all drive and card installation.

Three 120 MM fans in the case.
Three 120 MM fans in the case.

Not a professional wiring job, but good enough.
Not a professional wiring job, but good enough.

The Final Product
The Final Product

It's Alive
It's Alive!