Model-Memory Battery Replacement on a JR XS3 Remote.

I hate it when I do something that fits right in with the original theme of the blog and I don’t take pics. I replaced a dead battery on my JR XS3 3-channel remote recently, hacking in a battery holder in the process. Fortunately, I have 2 of these, so I did it again on the 2nd remote, taking pics this time.

Inside are 5 PCB’s, the main board, what looks like the transmitter frequency synth board, the throttle trigger board and finally the 3rd channel button board, and the charging port down in the handle.

The freq. synth board is held in with 3 or 4 small phillips screws, remove these and put them in a safe place. Then, remove the trigger. It’s adjustable, so when I put mine back together, I placed it as far forward as the 3 positions would allow.

Now, remove the main PCB. There are wires all over the place, but they don’t unplug. I guess the 2 cents per connection was more than JR wanted to spend. So we have to remove everything instead.

Be sure to catch the power switch slider that will fall off when you remove the main board. I temporarily lost mine. Now, heat up your iron or your solder-sucker tool, and desolder the battery. If you’re using braid, get yourself a desoldering iron like mine, on the left in the pic below. $25 on eBay, and worth 4x as much. I lost my first one that I picked up 2nd hand, and absolutely loved, so I get intense about this one.

In the picture of the PCB above, I’ve circled the solder points for the battery. My PCB is a POS. my traces wanted to pull up, so be careful removing the battery.

Now, take your handy coin-battery holder from Radio Shack and you will find that it doesn’t fit. That’s right. All this work and it won’t fit.

Life sucks, but then you remember your DREMEL tool. My rotary wrench (much like a cutting torch is called a “Hot Wrench”) gets a lot of work around here.

Take the positive tab off, this should be the tab that is on the side of the holder. It’s the one on top that holds the battery in place. Now take the dremel and cut off the plastic that lived where that tab was. Now cut a gap in the side to leave a way for the positive tab to sit next to the holder and still connect to the board. If you fit the holder up now, you may have an electrolytic cap that’s in the way. Cut the holder so it will fit around the cap. Mine needed a cut near the positive tab to allow the cap in, yours could vary, see pic above to see the area that will need cutting.

I didn’t take pics of the rest, apparently. But you can visualize it.

Test for fit, then remove the holder, and dab a drop of CA (cyanoacrylate or super glue) on each of the plastic pins that live under the holder. I had 3. Set the holder on the board making sure the negative tab is in the proper hole on the board, press it down to set the glue and then solder the negative tab in. Place and hold the + tab in the hole on the main board, oriented properly over the holder. Solder it in. Install a battery. You’re done. Reassemble the radio. If you’re like me, dress it up with some stainless buttonhead screws. Note that the steering wheel and the potentiometer that it works need to be aligned (ie: center the pot) before you slap it all together else your steering may not work. The best way is to fit the main board and the battery board up and slap a pack in, power up and test the steering.

Congratulations. While I don’t know how much JR charges to change the battery, you’ve saved it. IMHO, this is a crappy design in the first place, this battery should have been “user serviceable” from the beginning, mounted on the back of the main board, under the synth board. Unfortunately, unless you want to use a smaller battery and clip, this is how it has to go. The CR2032 holder stands too tall to clear some components on the synth board, and as I’m sourcing parts from Radio Shack (don’t get me started…) the selection is pretty slim. Someone more experienced may be able to perform a better hack, but I planned this from the beginning to be an easy hack; I hadn’t expected the dremel to come into play, as not everyone has one.

Give it a try, good luck and remember: You can’t sue me because you’re doing this at your own risk.