Blog Post by UngradedHow To Build a Impuls RC Apex with DJI FPV

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How To Build a Impuls RC Apex with DJI FPV – Video Transcript:

Today we’re building a high end five inch quad. We’re using a Impulse RC apex HD. Caddx Air Unit, Ethix v4 Stouts, the Tekko32 Metal ESC, sixty five amp, the HolyBro Kakute F7 HDV and the Crossfire nano receiver, let’s start.

Impulse RC apex HD

So the first thing to do is to assemble the frame. So if something to build on. The first thing to do is to insert the press nuts. You do this by using a screw just like so until they’re flush with the arm. And then we do this for all the arms. So now we have inserted press nuts into the arms. We’re going to do the same with the bottom plates. But now we’re using a washer and this crew. You have to make sure to insert the press nuts into the side without the bevel cuts. So now we have inserted all the press nuts. We can start assembling the arms. You will need both of the bottom plates and the arms and the keystone. You will also have to insert your stack screws. Now you can choose 20 by 20 or 30 by 30.

The Impulse RC apex HD frame

So it’s a good idea to secure two stack screws first because you can’t access those, if you install arms. Now we have installed the stack screws. We’re going to continue with installing the arms on the other bottom plates. We’re going to use eight mm screws with this aluminium cones. You don’t want these teight yet because otherwise you can get in the keystone. Now you install the keystone. If you’ve done that, you can tighten up these bolts. Then you want to use these special screws with aluminium cones to secure the other bottom plate. So now we have to insert the flight controller gummies to make everything fit. We have to cut down gummies that come with the ESC. Uh, it’s pretty easy. Just use flash cutter and it’s going to be OK. It can be hard to insert these gummies, but we’re using an small screwdriver and just kind of poking, poking it in. Just like that. If your using the same electronics as us, you just plug and play, you can connect to the ESC and the flight controller via the wire that comes with it. No need to rewire. I’m going to thin all the pads on the ESC. We made a mistake. You shouldn’t connected the batterylead yet because you have to pass it though the top plate first.

Ok, now before we attach the battery lead, we are going to pass it through to top plates, so we have to attach this. There we go. Now we can attach the battery lead to the ESC. So now everything is tinned and the battery lead is connected. We’re going to install the motors, we’re using 10 mm screws and we are using the landing feats that came with the Apex. So these are the new Ethics V4 Stouts. We chose these motors because they’re even more efficient and more efficient than the last generation. They’re great, they have great performance and they’re really light weights. With these motors, we can get about eight minutes of flight time before being gentle. So now we’re done with the motors. We’re going to install a capacitor, but the capacitor doesn’t fit in the back anymore because we’re going to use an Air Unit. So we’re going to extend it with some wires and hope it fits. First we have to find out how long the wires need to be. It’s a good idea to leave the wires a little bit longer than you actually need. So if you screw up, you can make things right. Then we have tin the wires and then we can connect the capacitor. So now we tin the capacitor, and attach the cables, the negative goes to the sides with the white stripe. But. Now let’s shrink the heatsink. We’re going to attach the capacitor. Right.

So now we’re going to solder all the motor wires. But first, we have to cut them to length. Always leave a little extra for if you mess up. It really helps if you have someone to help you with this. For people who don’t know, it doesn’t matter which way it goes to which pad, because you can reverse the motors in software and every wire can go to every pad. Always make sure to tin all the wires and pads, if you don’t do this, you won’t get a proper connection. Motor number now do this for all the motors. Now we’re going to attach the wire covers that came with the apex. So the wires don’t get chopped up. We will secure them with some electrical tape.

Install the Air Unit

Now we’re going to attach standoffs, they make sure the top plate and bottum plate stay in place. We secured the Motor wire covers, we installed the stand off. Now we’re going to install the Air Unit, although it’s a perfect fit. We’re going to use sticky tape because otherwise it’s going to cause vibrations. We have put in the Air Unit. This fits perfectly, but we used some double sided tape, just to be sure we printed this mount for the antanas. Now we’re going to put the flightcontroller back, connect the Air Unit, run the cable from the camera underneath it and then put everything together. Now we’re going to begin with the receiver we printed this mount for the receiver that sits where normally the OSD board of the Apex sits. Right now, we’re going to attach the camera to the camera plate. You have to use the small screws have come with camera. Otherwise it isn’t going to fit. So now we’re going to secure the camera. The apex comes with washers, so we use those because this camera is smaller than it’s intended on this built. So we attach a camera now we’re going to attach to immortal T antenna for Crossfire. We want to do this with the special mounts, but we still need to design it. So now we’re going to attach it with teirips. Make sure it’s nice and tight. We printed this antenna holder, so the antenna’s don’t pop out in a crash. So we’re going to secure it with teirips. Now we’re going to connect the Crossfire receiver to the flight controller. So now we’re going to tin the wires. The Crossfire receiver needs ground, five volts, TX and RX, so the flight controller your going to use ground. Five volts. T2 and R2. So let’s begin. So the only thing left is to put some nuts on the flight controller. Make sure you don’t tighten them too much because otherwise vibration dampening of the fire controller doesn’t work anymore. So hand side is good. If you are smart, you use some lock tight to make sure you don’t come loose. The only thing to do now is to program it. So let’s begin.

Beta Flight

Connect, you will start at setup if asks. You should calibrate the accelerometer just like this, but the quad on a flat surface and calibrate accelerometer then go to ports. If you wired everything the same as we did, then you should enable MSP on UART1. And enable Serial R X and UART2 then save and reboot. That connects. That go to ports, then go to configuration. You should to motor protocol DSHOT600 enabled bidirectional Dshot, put the bit low frequency on eight K and by receiver you shoots select serial based receiver and Crossfire, then again, save and reboot. Connect. Then go to PID tune at the moment, of this recording, we don’t have a perfect PID tune. So if we do have a perfect PID tune. We will put it in the description, so check the description for PID tune and filler settings. Let’s go to receiver. The receiver that we need to check the channel map. If it’s your first quad, then probably the channel map isn’t correct. You need to connect your controller with your drone and then you need to check. All the channels are correct. This throttle roll pitch and yaw for us. We need the channel to be t e a r. This could be different for your controller, but this worked for us. So if you want to know what your channel mapping is, go to your controller and check in the channel and wonder which channels are moving. If you use your sticks, then follow smoothness on 20 and save. Then go to Modes. In modes, you have to enable a couple of things you need to click add range by arm, then click on the AUX. Then if your control is connected, you can just click a switch and should auto detects the switch and you can track this this line to where you want the mode to be activated. So if you enable the switch, then the line activates when the switch is at that location. You should also enable Horizon. You don’t have to, but we use Horizon for some applications, so it’s right in that range. Then you switch to again, select your AUX channel, then put it’s where you want to. Then the beeper beeper is useful for if your quad falls out of the air and you can’t find it. You can activate Bieber to find it. For instance, in tall grass. So again, ad range selects AUX channel, then the last thing is flipped over after crash. We put flip over after a crash horizon and acro all on the same switch, so flip over after crash again add range. Then select AUX channel and then save. Then go to motors. For this, you need to plug in a battery, uh, make sure to use a smoke stopper if this is the first time you plug in your drone with the props of, very importance then understands the risks. Click master. Then use the arrow on your keyboards to increase the r.p.m. and so all the motors are spinning, then check the motor direction of the motor directions should be what you see in the left hand corner. If it’s not, it doesn’t matter. We can change that in BLHeli32, so make a note of which way the motors are spinning and which motors need to be reversed. Then I understand the risks and go to OSD. In OSD there are a couple of things that we use in OSD, but not all things that’s you can see here, that you can select work in the DJI OSD. So we use altitude, average cell voltage and battery current draw and battery voltage. You can drag these arround and put them where you want. Save and yeah, that’s that’s all you need to know in Betaflight.

Setting up BLHeli32

Let’s continue to BLHeli32. So let’s start with BLHeli32. First, you need to select the right comports. You can know which comport you need to use, because Betaflights auto connects. Then click Connect. Then click read setup. Probably you’ve checked off your motors to spin in the right direction. They’re not. Then you need to reverse them. Here’s how to do that. I need to reverse motor two and three. So I did select one, three and four. Then I say reverse motor direction and write setup. Then I select motor tree and deselect motor two. Then I say reverse and write setup. There are some settings you can do to enhance your performance. So motor timing should be on about 24 degrees. And remember, power can be around 35. That should motor timing should increase your power and ramp up power. It doesn’t really effect too much, except if you put it’s way too low. But this saves power. You can get former flight times so write setup. Also, you can enable sign modulation mode if you do this, you can expect smoother motors. So write setup. That’s it. Now we’re going to secure the top plate. Now he’s done. If you want to see this apex fly, make sure to watch next week’s video. And if you have any questions let us know in the comments, I want to thank you guys for watching and see you next time.

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