Remotely incrementing a (scoreboard) counter

Thread Starter

EriBoo

Joined Feb 9, 2022
12
Hi all!

I'm currently working on a little project for my dad, a 2-player billiards scoreboard that keeps of scores and statistics. All is working well, but there's a small (I hope) part I'm having trouble figuring out. I'd like to enable remotely incrementing the score and handing over the turn to the other player. My intention here is to 3D-print two remotes that can either be mounted to the billiard table, kept in one's pocket, or worn on a cord around the neck.

As a first experiment I have bought two sets of these:

https://www.tinytronics.nl/shop/nl/...les/433mhz-rf-afstandsbediening-met-ontvanger

(in case these details matter, the receiver is marked RX C6, the circuit board in the key fob is marked AK-TF04 and contains a PT2264 Remote Control Encoder)

I think they're pretty run-of-the-mill standard 433Mhz key fobs and receivers and I can get one of them working, no problem.

A couple of reasons why this isn't ideal:

  • Can't distinguish between the key fobs. I had hoped to find a couple of dip switches inside the plastic casing, so I could make them both send out a different signal. There is of course the option of using the A & B buttons on one of the remotes and C & D on the other, but that's less than great. Especially since I could theoretically provide four function per remote, if I could tell them apart.
  • It's got an odd/clunky shape. For the purpose of building this into a 3D-printed remote, the options are very limited. The PCB is a bit wide (to accomodate the 12V 23A battery, I suppose, I had never seen a battery like this: https://www.amazon.com/LiCB-23A-Alkaline-Battery-5-Pack/dp/B06ZYRCP2B)
  • It's simply not very flexible.

Now I have a couple of questions:

  1. Disregarding my explanation of what I have already tried, what would you think, is the best solution to the problem of remotely incrementing a score counter? Is it even RF or something completely different? I do not want it depend on line of sight, so I think that excludes IR.
  2. With the RF key fob solution in mind, is there any way to "build your own remote"? I'm guessing the PT2264, some sort of oscillator, a power source and an antenna would go a long way, but I also realize that is currently waaaaay above my skill/knowledge level. It is however something I'm willing to sink a lot of time and energy into, because figuring stuff out that I barely know anything about it tremendous fun to me. I'm really looking for some pointers on where to even start though.
  3. With the RF key fob solution in mind, is there any way to distinguish between the remotes? There seem to be two solder pads on the back of the AK-TF04 key fob PCB (marked A0), which kinda look like a jumper, but I'm not sure and cannot really find much detail on it.
 

MisterBill2

Joined Jan 23, 2018
12,745
An IR link does not need to be line-of-sight if the proper arrangement is used. Consider how the TV remote control works. Atthat point, if there are only a few functions to be controlled, a brighter IR led and a multiple frequency oscillator will be needed for the transmit part, and a PLL tone decoder on the receive end. And just copy the receive front end from a TV remote, or even use a TV remote receive module.
 

Ya’akov

Joined Jan 27, 2019
6,289
These modules have a unique ID on each transmitter. Using one receiver per transmitter, you could have as many unique controls as you want. They have four outputs which are not mutually exclusive, you can tell if more than one button is pressed, and which ones. This means you can add more combinations than four, if you want.

I have used these and they work well but the critical bit is the antenna. You must make sure it is as close to the antenna terminal as possible. Loading down the transmitter will make it simply not work. The little spring antennas that come with them will be fine in your fobs, but I would recommend better antennas for the receivers to improve performance. (Those this may not actually be a problem so it is worth testing.)

You can power the transmitters with a since lithium polymer cell, and with a small battery management board, you could easily make them USB rechargeable. I am done this very thing, it works fine.
 
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