Hi everyone, thought I'd share my journey on this model. First off, I think Loksound decoders are great and I have a handful of locomotives running them. That being said, this particular example had a few issues that I wanted to address and converting to TCS seemed to make the most sense.
1) Current pickup was / is abysmal. I don't have an explanation for this, but this thing will not make it around a sharp curve, let alone a turnout, without cutting out at least the audio. All efforts to clean the wheels, make sure I have at least one truck that can rock side to side, and check that both trucks pick up current did not improve things. So I wanted a keep alive, which meant I needed a new motherboard. Yes, I believe I could have added a KA to the Loksound setup somehow, but #2 below still wouldn't be solved. Here's a video that I took while trying to troubleshoot the pickup issues.
2) The sound quality of the prime mover was not awesome. Beyond notch 4 or so, it just turned into white noise; it could have been constant radio static for all I could tell. Maybe this is prototypical, maybe not, but it just didn't add much to the experience.
3) The sound volume itself was very low and was drowned out by the sound of wheels on the rails at anything over medium speed (and I configure my locos to top out at less than half speed usually). I wanted to try a different speaker.
Parts list:
Rapido packed a crazy amount of lights into this thing: two different color directional marker lights (that's 8 separate bults), 2 directional gyralights, 4 lighted number boards, 2 headlights, 2 emergency lights, 2 ditch lights, and lighted guages in the cab. So getting all of these to work with a new decoder and motherboard was pretty daunting. Furthermore, it's a tight fit! Every cubic milimeter that wasn't used to make the thing go, light up, or generate sound was metal weight. Impressive engineering.
I didn't take a lot of pictures before surgery, but here's one with the OEM motherboard and the TCS 21-pin decoder. All of the space behind the docoder under the long hood is full of OEM speaker.
I discovered that when I lifted off the access cover shown above, issue #3 (sound volume) basically went away. It turns out that the pieces of the shell fit together so perfectly that there is no way for the sound to escape from the small OEM speaker.
Speaking of the OEM speaker, I decided to retain it because what it lacked in low frequency response, it made up for in high frequency response and the combined soundstage of it plus a TDS Supersonic that I placed in the cab was pretty solid.
Anyway, I decided to cut out the vents in this cover and add some mesh screen in their place, allowing the port of the OEM speaker to fire directly through one of the grills. This made a big difference and can't really be seen unless you're looking for it.
Of course I tried just swapping the decoder onto the OEM board first, and while the loco ran fine (except for those pickup issues), many of the lights didn't work, which was not unexpected.
Here are the light functions with the Loksound decoder. Turns out Rapido uses Loksound sound functions to make some of them work!
And here's a rundown with the TCS decoder, defaults settings.
The good part about replacing the motherboard was that I knew what each output did, so it was just a matter of figuring out which wires did what (all 28 of them!). For this I relied on the small amount of common sense I had and a large amount of trial and error.
For the front and rear lightboards, I decided to skip the white marker lights. I wired the rest of these wires so that the headlights and green marker lights all went into the same pad, the gyralight to F1, the number boards to F3, the emergency light to F4, and the ditch lights to F5. I tried to combine the ditch lights and number boards into the same pad, but the current draw was too high and they were really dim.
Here's some wiring speghetti while testing:
Here you can see the cable management guides under the cab, which I eventually use again.
A little cleaner...
And the final arrangement before putting the shell back on. The keep alive fits very nicely next to the OEM speaker box (I got lucky).
One last close-up of the OEM speaker port:
Ready for action after several layers of dull coat and minor weathering:
And finally, here is a video of the finished product!
https://photos.app.goo.gl/gMwMNr6FxfHHkdht7
I congratulate you, that is quite a project. Links to google photos work for the OP and sometimes for others, but not consistently.
I can see your videos, for now.
I don't see a link to the OEM speaker port picture.
Henry
COB Potomac & Northern
Shenandoah Valley
None of the pictures are showing for me. I'd be interested in seeing the conversion ....
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
I'm nothing short of astounded that you needed a "keep alive" for a Rapido diesel! I suspect the real problem is their super-super-detailing has caused there to be something obstructing the truck from moving freely on curves. I hope you contacted Rapido before doing all this work; if there was something wrong they may have wanted to see it so they could correct it in future runs.