I recently acquired a Bachmann 2-6-0 “Raton”, which is a post-2017 ‘gen-2’ version with a plug-n-play socket in the tender. It came from a lucky auction win, and was brand-new in the original box.
It was pristine, and I originally planned to sell it, but I have a couple of Revolution p-n-p steam sound boards so I wondered if one would fit, with a battery, without altering the look of the loco.
In case you wondered, the answer is Yes!
With the tender top off, I dropped in a 4S Li-Ion block (designed for a robot vacuum, I believe - I buy them on Aliexpress.) It fits tightly behind the motherboard, though I had to move the speaker wires that were routed over the back.
It’s also tricky to re-mount the top. You have to push the battery in to the top and tilt the top into the holes in the floor.
The big issue when fitting battery and r/c to any loco is to find somewhere to fit an on/off switch and a charging jack. I was pondering it, and finally noticed the coal boards (?) at the front would pull out, and behind was the front wall of the tender. The motherboard is a little further back, so there was room for the switch and socket on the wall. With a little filing, the coal boards could be slid easily up and out. The main coal load is a lift off metal weight, so access is no problem.
And here’s the tender with the switch and socket mounted on the front. One pair of wires (male pins) goes to the battery from the socket, and the other (female pins) connects the switch output to the Battery input on the motherboard. [I use regular conventions for plugs - batteries have a female socket to reduce the chance of a short circuit.]
There’s a 3A ‘polyfuse’ between the battery and the switch. Lithium batteries can produce very high outputs, so it’s best to protect the wiring with a fuse.
With the Revo board installed, it’s a tight fit. The weight is hollow, so there is lots of vertical room. I crammed the ‘bind’ button down the back - you can see lots of black/white wires down there.
With it all connected, I grabbed my Revo transmitter (TX) and programmed it for the loco “Raton”. I turned on the tender (don’t need the loco as everything goes through the tender on this version,) and linked it. All seemed well, except no sound.
After some discussions with @Stan_Ames I confirmed the Revo does not have p-n-p pins connected to its speaker output. An email from Crest confirmed the sound was not p-n-p. So I plugged in the sound wire supplied with the Revo, and, noticing that all the p-n-p functions are lined up on the side of the board, I soldered the speaker wires to the motherboard spkr+ and spkr-.
The sound now worked, except only momentarily [that’s a clue.] I recalled that the function keys are on an aux menu in the TX, and can be set to Latch or Momentary. Setting it to Latch solved that problem.
So it was off the Jerry’s Spa Creek & Mckendree Railroad, the local garden track where I have running rights in exchange for maintenance duties! As you can see from the first video, it works very nicely.
Guess I have to sell it now. . .