Three Button Remote Control.
I designed a 3 button remote control for a project I’m working on. Perhaps someone will find it useful.
It’s designed to handle a 30x70 board such as a prototyping board. In my case I repurposed a 30x70 board I designed that supports an RFM69CW transceiver and an ATtiny84A MCU. This board also has a small DC-DC step down converter chip (LM3671, very low quiescent current) that’s used in such things as cell phones. As you can see from the photo, most of the board is empty.
I’m not recommending any of the above components. If you decide to use this design I’ll leave it up to you to come up with a remote control transmitter circuit. If anyone wants the schematic + sketch I used I’ll be happy to send it to you, just let me know. It’s pretty basic but it uses parts that aren’t that common so I figured it’s not worth publishing it here.
I printed all 3 pieces at 20% fill, no support. Depending on the accuracy of your printer you may need to sand the cover edges a bit to get them to fit.
The remote control body holds 3 AAA batteries using battery spring plates. I got these from Banggood.com . You can probably find them for less from other sites but their dimensions may be different. The plate dimension for the plates I used is 9x9mm.
The Banggood.com screenshot has changed since I purchased my plates last year so I have no idea if the dimensions are the same.
To install the plates you need to bend the tabs over so they’re flat on the back of the plate (see photo). You then solder the wires to the tips of the bent tabs and insert the plates into the slots in the remote body.
The jumper wire lengths are determined by placing two tabs in the remote body where they will be used, just enough to keep them in place, then cut and bend a wire with stripped and tinned ends. The wire should be flush with the top of the plate so that when it’s installed it will sit in the pocket between the plates. Once installed you can’t remove them without destroying the body. The plates have small burrs that prevent the plate from being removed. The wire runs up from a tab, across flush with the plate top edge, then down to the next tab.
The long negative/black wire should be pressed into the channel that runs along the edge of the battery compartment (see photo).
The switch board is a piece of a 20x80mm prototype board cut to 30mm.
The switches are 6X6X10 DIP Tactile Momentary switches. The 10mm length of the button is measured from the back of the switch, the side that touches the board.
An example of this switch: https://www.aliexpress.com/item/100PCS-6X6X10-DIP-Tactile-Tact-Mini-Push-Button-Switch-Micro-Switch-Momentary/32634464241.html
In the crappy photo I took of the back of the switch board, you’ll see hole columns M through X. The switch legs are placed on the top and 3rd rows of the board in columns M-P, Q-T, U-X, with jumpers between the 3rd row PQ and TU, with the common ground (black wire) off of X.
The support holes for the mounting screws are made by enlarging the bottom row holes P and U. I also made a cut in between the mounting holes to run the wires but you could probably run them without one.