FrSky Taranis Antenna Upgrade Part 2

Well it seems that I am unable to stop modifying my FrSky Taranis so here's the next step.

Firstly I do not take credit for the design of this antenna. That came from the great IBCray and his tutorial for the calculations, theory and measurements can be found here. So I'm not going to go over those again. This is just my build log and application of his design. So that being said lets get started.

Things you'll need.

For the antenna:
1. A small coax cable
2. Copper or steel wire, about 14 AWG
3. Metallic plate
4. Two Nylon bolts
5. Plastic container (optional as this is just the cover)

For the antenna mounting (this is just my solution but many others would work as well):
1. 12mm x 12mm square wooden dowel.
2. Two M3 bolts (atleast 30mm)
3. Heat shrink


Other:
1. Heat shrink
2. Hot glue
3. Solder


Lets get to the modding......




Step 1.
Cut the backing plate and the wire. I used G10 board for the reflector plate.

Step 2.
Start bending the wire at the section lengths for a 2.4 Ghz (see the IBCrazy thread for the calculations to get the dimensions for your frequency)

Step 3.
The reflector plate and the resonator.

Step 4.
Drill a hole in reflector for the coax cable and also mount the nylon bolts to hold the resonator.

Step 5.
Strip the coax cable back and solder the shielding to the reflector.

Step 6.
Solder the resonator to the coax cable and glue it to the nylon bolts

Step 7.
Glue the coax cable and nylon bolts to the back of the reflector and glue the plastic container to the front of the antenna.

Step 8.
You'll need to get the coax cable into the Taranis so instead of drilling into it I ran it though the hole in the ORX module left when I did the antenna mod on it.

Step 9.
New antenna connected to Taranis.

Step 10.
Solder new coax cable to the Taranis module board where the other antenna was connected.

Step 11.
Antenna ready to be mounted.

Step 12.
Cut four sections of the dowel about the length of antenna. Doesn't matter if they are a bit shorter.

Step 13.
Clamp them together and drill a hole where they meet at the top about 4mm in diameter.

Step 14.
Take the handle off the Taranis and put some heat shrink over it to give the clamp more grip.

Step 15.
Drill mounting holes in the dowels just bellow the main semi holes.

Step 16.
Screw the mounts together with the M3 bolts and clamp them to the handle of the Taranis.

Step 17.
Glue the new antenna to the mounts.

Step 18.
All Done!

Note: this reduced my SWR reading down to 16. This is probably fine but I read that to get it even lower you need to make sure that when you're soldering the coax cable to the board you want to expose a very very small amount of the core and make it as close as possible to the soldered shielding.

FrSky Taranis Antenna Mod

So the FrSky Taranis is an awesome radio but with a little modding you can make it even better. Due to its ability to to use both its internal FrSky module and another one in the port on the back it has amazing flexibility. The only problem with using an external module is the fact that the antenna sticks out the back and won't let the radio sit flat on its handle. It also gets in the way when you try to carry it by the handle.

So here's what I did....

1. Take the module out of the radio and also take the battery out so you don't short anything out.

2. Unscrew the six screws in the back of the radio and open that puppy up. Always a little scary I know but this radio is designed to be opened up so you can change the mode if you want to.

3. Open up your module by unscrewing the antenna and the four screws in the top. I'm using the ORX DSM2 module from Hobby King so I can fly my Nano QX and my old foamies with this radio. The little antenna cable you here see I got from eBay for a few dollars. Just get a RP-SMA antenna cable like this one from an electronics store or eBay.

4. Put the module shell back in so you can drill through into the inside of the Taranis like I've done here. The hole just needs to be big enough for the small end of the cable to go through. Be careful when you drill through that you don't hit anything inside the Taranis. If you drill through here like I did you should be fine.

5. Now drill a hole in the top of your Taranis. This can be anywhere you want the second antenna to be mounted. I put mine up here behind the main antenna. The hole needs to be just big enough to put the big threaded end of the RP-SMA connector through with out letting the whole thing (the collar and nut) fall through.

6. Put the big end of the cable though the big hole and the little end through the little hole. Once you've got the big end though, put the washers and the nut on the top to stop if falling back into the Taranis.

7. Connect the little end of the cable to the board in the module and put the board back in the module case.

8. Close the module up and put it back in the case. You can close the hole left by the antenna with some tape if you want.

9. Screw the second antenna onto the SP-SMA cxonnector and close the Taranis case. One thing to note when putting the screws back in. If you don't hold the two halves together the screws won't grab in the front half and they will push it open. So just keep the two halves held together while you do it. Also make sure you put the top two switches back in the right way, brown wire to the top (like all the others).

10. All done!

11. It works :)