Installing DIY Button in Radiomaster TX16S MK II

by Oscar
Installing Diy Switch In Radiometer Tx16s Mk Ii Momentary Latching Push Button

I had always wondered what the hole on the back of the TX16S MK II is for. You can actually drop a push button right in there, which is quite useful for just a few dollars. The installation and configuration are quite simple too.

Some of the links on this page are affiliate links. I receive a commission (at no extra cost to you) if you make a purchase after clicking on one of these affiliate links. This helps support the free content for the community on this website. Please read our Affiliate Link Policy for more information.

Where to Buy?

Purchase DIY Button here, only $3.99, options are latching and momentary buttons:

It’s a pity that Radiometer didn’t put that switch in the TX16S MK II, maybe trying to sell them as upgrade and increase revenue. Not everyone needs it anyway so it makes sense to leave it and make the radio cheaper.

How to Install DIY Button in TX16S MK II

To install the DIY button, open the radio first.

Radiomaster Tx16s Mark Ii Mkii Radio Transmitter Tear Down

Drop the button in the hole. Thread diameter of the button is slightly under 11.9mm.

Installing Diy Switch In Radiometer Tx16s Mk Ii Back Plate Housing

There are two connectors you can use on the PCB.

Diy Switch Tx16s Si Sj Connectors Pcb Pinout

The connector on the left is SJ, the right is SI.

Note that those connectors have some pins left after connecting the switch, in theory you can connect analog input like a potentiometer or slider. But an On/Off switch only requires two pins to work.

Connect the switch to the PCB.

Installing Diy Switch In Radiometer Tx16s Mk Ii Connect Pcb

Go to the hardware page in system menu. Scroll down to SJ or SI and set it to toggle. Once that’s done, when you push the button the arrow next to the name should change.

That’s it.

Installing Diy Switch In Radiometer Tx16s Mk Ii Opentx Edgetx System Hardware Toggle Si Sj

Possible Applications

The DIY button could be useful for:

  • Instant trim
  • Timer reset
  • 2-step arming
  • For activating Rescue mode
  • Throttle limiter switch (e.g. reduce max throttle to 50%)

Here’s how to setup reset timer in global function in system menu.

Installing Diy Switch In Radiometer Tx16s Mk Ii Reset Timer Si Sj

Leave a Comment

By using this form, you agree with the storage and handling of your data by this website. Note that all comments are held for moderation before appearing.


max 28th July 2023 - 7:51 pm

can you put both led lights and switch or its one or the other? looks like im missing room for the button since i have the leds

Markus 29th October 2023 - 6:24 am

I’m wondering the same thing

RepterFPV 15th January 2024 - 12:33 pm

I just did the LED and Button mod and I can confirm: yes you can have both, but you’ll need to combine the two connectors. You can do that by taking out the wires from one of the connectors with a flat head and inserting it into the other connector.

Based on the pinout (linked below), you’d connect the switch to pins 4-5, and you connect the LEDs to 1-3 (GND and Vcc respectively).

B3ar 1st May 2024 - 5:10 am

Amazing info! I was thinking about soldering the LED wires to the DIY switch’s wires
With your info, I de-pinned the wires from the LED’s JST connector. Then connected the black wire on Pin 1, red on Pin3 of the DIY switch’s JST connector. That diagram came in clutch, thank you!

Gerhard 25th May 2023 - 8:43 am

What is the type of the plug. JST?

Brian Flores 1st September 2022 - 2:08 am

I think you have a typo in your title. Should not be radio master? Not radio meter?

Oscar 1st September 2022 - 11:39 am

Thank you!