Using a D104 Microphone with Zello

OH, YES I DID!

lol ok so maybe it's a tad bit silly, but if I'm going to set back my smart device 40 years by putting a push to talk application like Zello on it, THEN I WANT THE FULL EXPERIENCE... Besides, when my 11 year old son saw the D104 in action for the first time, he asked about it. That opened the door to talk about it, and he actually thought it was really cool and wanted to talk on it too... ....and for me that's what it's all about :)

The game plan

My initial plan was to take one of my extra Bluetooth iTalkie speaker mics, tap into the circuit board and give an old D104 mic a Bluetooth upgrade.

Why the iTalkie? Because I knew the mic had HD sound, unlike other Bluetooth speaker mics out there. I also knew the battery lasted a very long time between charges.

Simply put, I would:

• move the mic element from the Bluetooth circuit board to the head of the D104, and use the existing wiring.

• locate the mic wiring from the neck of the D104, and wire the mic back to the Bluetooth mic circuit board

• using the wiring of the D104 PTT switch, tap into the PTT switch on the Bluetooth mic circuit board

• remove the speaker from the Bluetooth mic board and convert into a line out jack. This will extend from the base of the microphone in a curly-Q wire. (Which will help with the D104's original look)

• tap into the Bluetooth mic's on/off switch, and wire an extended switch which can be reached from the existing hole from the bottom of the D104

• run a 1 foot extended micro USB (micro male to micro female) wire out from the micro USB input which would simply hang out of the back with the line out wire so the mic can easily be charged.

The Draft: Finding a decent enough D104 microphone to work with

I didn't even care if it worked. I just needed the shell.

I found it on eBay.

The chrome was faded and hazy, the wire hanging from it was shabby, and the seller didn't even know if it worked or not. They wanted $10.00. So for THAT price, I jumped on it. I figured if it didn't clean up, I would give it some crazy paint job or something, sort of like the D104 mics from the game Fallout 4....

Pregame show

I finally received the D104 and the first thing I looked at was the lollipop head. Was it ever dropped and now the head is wobbly? Nope! The head is on tight..

Then I needed to know if it would clean up. So I started with taking it completely apart.

Believe it or not, I used Windex and paper towels on all of the chrome pieces with a little riggerous wiping, and OMG the thing shined right up!!! I didn't need to get crazy with polishes or anything like that at all...

For the grey base of the mic, I thought I would going to have to paint, but it cleaned right up with simply using Clorox wipes! I couldn't believe it.

First thing I did was tested the PTT switch. It worked, YAY!

The next thing I tested was the element. It didn't work. (I didn't expect it to)

Game time

So, with the head of the mic still taken completely apart, I gutted the old element. I still used the old internal casing, strapped the mic element from the Bluetooth mic, and soldered it to the existing wires. (You can find these mic elements everywhere on the web btw)

Personal foul

So I went along with the plan I had laid out above. And I actually had it working!!! It sounded great! The PTT worked great! But then I continued to do some tweaks, and then I F@$#@! up the circuit board.

How did I mess up the board? The circuit board soldering points are so small and close together, for one. And the wires to where the mic and speaker go are soooooo thin. Basically, the wires to the mic accidentally pulled off the board, and I tried to solder it back, but in doing so, bridged the two points together, and then I ruined the board trying to undo it. They don't make circuit boards like they used to.. And they are not hack-friendly.

SOOOOOOOO, I had to go another route.

Like any good football coach, I had a backup plan - JUST TO GET THE DAMN THING WORKING.

Halftime adjustments....

At this point, I turned on the BT camera shutter on/off switch, and that's going to stay in the on position forever. The new on/off switch will be the switch that's built in to the AAA battery compartment.

Now it's time to connect to a device via Bluetooth. This shutter button is basically a Volume up button. When in the camera app, hitting this button will take a picture, just like if you click the volume up button on the phone.

But in Zello, we can map this button as the PTT button. Once mapped it's time to test:

IT WORKED!

Next, I fastened the battery compartment using sticky-back tape so that the on/off switch is exposed from the existing hole on the bottom of the mic:

Lastly, I wired the mic out to a 3.5mm plug, which hooks directly into a USB sound card. I then need to wire the line out from the sound card to an external speaker.

Touchdown