• Tom McMeakin

Building a comms headset

After checking out the market for off the shelf paramotor comms units and seeing numerous videos of pilots making their own helmets (Here’s my personal favourite), I decided it was possible, much cheaper and even more rewarding to make my own comms setup. In this post, I share how I adapted some basic ear defenders for less than £75!


To start with I have the Icaro Solar X helmet with basic 3M Peltor ear defenders to use as a base and to install my comms into. I wanted to make sure that the safety aspect of wearing a helmet remained.


I will outline the parts used, how I put it all together as well as any issues that I encountered and improvements that I would make if making this setup again.


Parts list & price:


Build Cost (not incl. helmet)

£74.60


Total helmet setup

£324.60


I wanted to make sure that the bluetooth unit was able to make calls and that I had decent speakers. You could save £15 on speakers just by using the ones that come with the bluetooth unit. The reason that I upgraded is due to the reviews of the tinniness of the integrated bluetooth speakers and I do not regret my decision.

Money can also be saved by searching around for other grommets, in reality all I needed were 3x 6mm ID grommets. I purchased the pack so I can use them on other projects.


The Build


Now that I had all the parts, I decided that my first priority was to install the PTT button and to wire in the Baofeng speaker parts. This is a separate system than the bluetooth and was the priority of the build. As I will be using this helmet during our guided safaris, I needed this radio to work as a minimum. If it did not, then I would have to splash out the cash on an off the shelf setup… Thankfully it was easier than I thought!


1. Creating the cable


My first modification was to the Baofeng 2-way speaker. This unit comes with a long coiled cable and all the parts that I need to create the PTT setup.

After unscrewing the plastic casing, you can see how simple this unit is. The first thing to do was to verify the wiring diagram that I pulled off the internet.

This is easy to check using the markings on the board and a multimeter. Once confirmed, I made a note of the wire colours and used these throughout the project.




I then cut and trimmed the wires and soldered them into the mini-xlr plug using the following pins (I couldn't find any diagrams of this online so I just winged it!). As I did not follow a standard, it is essential to keep this information in case I need to make a new cable at a later date.


I made sure to also use the same colour wires on the button, speaker and mic for ease of installation.


Pin 1 - Red - Mic +

Pin 2 - Black - PTT

Pin 3 - Green - Speaker +

Pin 4 - White - Ground


Finally, to ensure I did not pull on the solder joints, I taped up the cable to the plastic part of the plug.


Here is the finished cable.



Note: I didn't throw the rest of the unit away - the speaker and microphone are used for this system!


2. Adding the socket & button to the ear defender


This next part was easy - firstly locate where the mini-xlr socket and PTT buttons will be. I chose the left ear cup as I use a right handed throttle. I placed the socket near the bottom and the PTT in the middle of the cup. I use a red button for the PTT, not for any specific reason. Photos not taken until all buttons were installed as I put both buttons in at the same time.

Then drill the holes into the outer plastic, clean up and burrs and screw in both the button and the mini-xlr plug... Simples!

For the inner plastic bit, I made sure the holes were much larger as this moves once the ear defender is clipped together.

If you watch some videos on YouTube, it seems as though people tend to remove this plastic part - I could fit all the electronics inside and keep the majority of the foam so there was no need to remove it. This therefore helped to maintain the integrity of the sound protection.




3. Aligning the microphone


For now, I located the position of the microphone port, drilled a 7mm hole and inserted a grommet. I did not insert the microphone as this needed some modifications to work with both the radio and bluetooth units.

Again, I put this on the left ear cup, in a comfortable position - pretty straight forward.



4. Wiring it up


I de-soldered the original wires from the speaker of the Baofeng unit and soldered on a green and white wire long enough to pass around the foam inside the cup and to locate the speaker at a later stage.

Note: I only have 1 speaker in the left ear for the radio - adding a second to the right cup could be an improvement I make in a future update, but I considered one would be sufficient after testing and was the simplest option to build.

I de-soldered the microphone from the board to use later, but for now tested with the microphone unit I bought.

Without soldering into place, I tested each aspect of the radio setup and to my surprise, it was all working as expected!


Bluetooth Unit


Now that the radio setup is complete and tested, I got started with the bluetooth integration.

Again, I made sure to draw out my plan and double check the wiring to make sure that I would not make any silly mistakes. I had looked at a couple bluetooth options, and although the button functionality seems back to front (hold vol - to go forward a track, hold vol + to go back!?) it was the easiest to modify and had a long cable for charging.


1. Planning the installation


Just like before, I needed to plan the integration of the unit, where I wanted it to be located, button position and most importantly the wiring colours. Because I bought 12 core cable. I had 12 different colours to choose from, making sure I would not mix up the wires when soldering them into the fiddly ear cup. This wasn't intentional when I ordered the cable, but came to be very useful indeed!


Here are the colours I used for each connection - mentioned here just so that you can reference against my pictures. The colours do clash with the radio unit but as these are 2 separate systems with clearly different connections it wasn't an issue:


Mic + Turquoise

Mic Ground Brown

Left Speaker + Orange

Left Speaker - Purple

Right Speaker + Yellow

Right Speaker - Blue

On button Grey & Pink

Vol - button Black & White

Vol + button Red & Green


Due to the button placement that meant 6 wires for the right ear cup and 6 which are redundant on the cable between ear cups.

This isn't a problem and perhaps I will make use of them if I ever upgrade the headset?


2. Button setup


Again, just like with the radio integration, the button installation is very simple.

I located the On/Off button above the PTT button on the left cup (I chose blue for this for Bluetooth) and the Vol + and Vol - on the right ear cup, one above the other (black and white).

The holes are drilled into the outer shell and the buttons installed. Just like before, I made larger holes in the inner plastic to allow for movement during installation. Simples.



3. Modifying the bluetooth unit


This next part proved tricky and I ended up scrapping the first bluetooth unit after damage - the main reason being that I was not using the correct tools!

After you remove the plastic casing (keep this for later to protect the circuitry) I was surprised at how small the bluetooth chip actually is!

The issue with this board is the installation of the microphone. Rather than being soldered through the board, or attached via wires separately, it is soldered directly onto the board.

To remove this microphone, use a heat gun (not a soldering iron and brute force!!) and gently remove with tweezers.

You will then find 2 concentric circular soldering ports, the central one being the ground and the outer ring being the positive side.


Unlike other bluetooth units I found, this one contains an extension wire for the USB charging port which is invaluable for someone with poor soldering skills like me!

I was able to pass this through the ear cup. No need to remove / resolder the micro usb… winner!


The buttons on the board have 4 outputs, 2 are connected on each side. Rather than removing the buttons, I soldered on top of 2 of the 4 connections and held the wires together to short and check the functionality.


I cut short pieces of wire and soldered the buttons and microphone points only, leaving the speaker wires attached and cutting the cable halfway along. This avoided potential damage and I was able to maintain the integrity of these joints.


Ignore the colours, this was the damaged board which I was practicing my soldering with!


Finally to secure the board and protect my weak soldering joints, I drilled holes into the plastic casing, one above each button and one above the mic to feed through the new wiring and put it back together, secured with tape.

Finally, I tested the microphone again by making a call, tested the button extensions and was happy with the outcome!


4. Modifying the microphone


The microphone I purchased came with a 3.5mm port at one end. Obviously I carefully cut this off to allow the microphone and wiring to be removed.

The plastic gubbins on the end of the mic were also removed. All I wanted from this was the metal gooseneck and the microphone itself.


After soldering on the correct coloured wire (as per my plans), I was only able to feed through one of my 4 microphone wires (2 per mic - one for radio and one for bluetooth). The other 3 wires were wrapped around the outside of the gooseneck and held into place using heat shrink - amazing material!



All that was left to do was to put back into place the foamy covering and tape into place. This isn't the best looking but does the job!

I could then feed the microphone gooseneck with the 2 mics attached into the ear cup.


5. Adding the cable between ear cups


After checking that I had the right length between ear cups and enough free wire inside for soldering, but not too much to look like spaghetti, this was a simple task.

The wire itself is ~6mm thick and so I used the same size grommet as the mic once my holes were drilled in each cup.

Once installed, I stripped and prepared each of my 6 wires I planned to use for the right ear cup and tucked the others to one side.


6. Soldering all together


Just like for the bluetooth unit, I added short extension wires to the buttons so that I could just solder wire to wire. I am really glad that I took the effort as this made the job much easier!

Due to the fact that I had colour coded all the wires, all that was left was to solder and heat shrink the joints.



Then, I added the speakers into each ear cup, covered with a small layer of the foam and completed one final check of both systems.



Finally the last step was to put it all back together - This was as simple as to cut up the chunks of foam and fit as much back into the ear cup as possible to maximise the sound protection.





I don’t notice a difference in the noise protection that these modified ear defenders provide in flight and am very happy with the outcome of the build!


This took a couple of afternoons, mostly due to the mistakes I made to the first bluetooth unit, but also because I took my time to make sure that everything was installed and connected correctly.


If I were to do this again, the main changes that I would make would be firstly to take a bit more time and care to solder up the bluetooth unit.

Next, I’d spend a bit more time on the microphone boom and ensuring that all wires are covered, not around the outside of the gooseneck!

Finally, because the radio and bluetooth are 2 different systems and installed as such, my music doesn't stop if I am contacted on the radio. I would spend a bit more time and effort creating a single system to perfect this build so I don’t have to pause the music manually.

Overall, I am extremely happy with the outcome - the sense of achievement and the huge cost savings vs an off the shelf part. Let’s just hope it is robust to last years…!


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