Bamboo SL Sound Generator
Early this month, I was in Sydney for a weekend and it co-incided with the AMRA Annual Model Railway Exhibition. I was disappointed to not see the usual Japanese Layout by a well known Australian modeller in the Japanese N Scale realm... but found enough goodies in the 2nd-hand junk boxes to satisfy my need for Japanese stock.
An EF81 (missing one panto and other bits) was still for sale from another seller for $80 and I passed on it again as, although I'm sure it'll run fantastically, I don't want to have to spend the extra money (and time search Poppondetta) for all the missing components.
And then... the find of the day... A, and I quote ”BB サウンドシステム SLドラフトN” or translated to: "BB Sound System SL Draft N". [Note: SL stands for Steam Locomotive in Japanese, they've coined the acronym.] When I saw it, I could only guess that it made SL sounds... and should be towed behind an SL. I asked the price, was told $10 and I didn't even ask if it worked, as I just wanted to get it and test it instantly.
On the train back to the city (2 hour ride) I read the instructions... hah... read them like a picture book! I could read the Katakana.. and that hinted something at a 'Power pack' and 'SCR timing pulse'. I thought I'd just bought a lemon that required some magic to get the chuffing happening... boy was I wrong!
If anyone wants to look at this image and give me a proper translation of it then go ahead... I'll post it here. Otherwise, when I get the time, I'll attempt to type it in to Google translator and see what it spits out. I really should've studied Kanji further after Uni
Inspecting the Kato WAMU freight car (damn heavy!) I saw that there was a reed switch and a magnet glued to the axel. Primitive technology from Japan... but considering the age of the paper the instructions are on, I'm guessing this whole thing is over 10years old; but i'm yet to actually research it. Anyway, when rotating the axel you could hear the reed-switch clicking... meaning that it would be the 'pulse' required.
Opening it up, very gently, I found a reasonably dated PCB with quite large components.. but everything fitting nicely. There is a standard (what looked like a microphone) speaker mounted downwards and they've also added weights on the inside of the shell.
Finally, tonight, I put some voltage to the unit. I had to turn my Kato Powerpack up to notch '2' to get it hissing... and it sounds good!... I then pushed it along the tracks and the chuffing started... I realised that I could quickly get it to chuff way too fast and sound like a machine gun. After attaching my MicroAce steamer, I realised the main issue; the voltage required to start the sound was so high that the steamer was already flying. At this speed, although it sounded ok, it was still too fast to be enjoyed. When there was no loco on the tracks and the voltage was high, the sounds were great... you could even lock the reed switch open (at the sweet spot) and the chuff would continue forever... as in when an SL releases pressure at the end of a trip.
I then had a closer look at the circuit board to see if I could drop the required voltage to get the sound moving and something dawned on me... The sound worked in both directions... meaning that the circuitry had to work either way the DC voltage was supplied... this meant it had to have a bridge-rectifier in it already... DCC AC Voltage here I come!!!!
Of course, I ran out of time to test it on DCC and I also have no SLs DCC'd up. My MicroAce steamer seems to have a large enough tender... but I love that thing and don't want to hurt it. It also manages to suck power through it's driving wheels and so it'll be a task to convert it.
Videos!
This is the unit running on DCC. I don't have any steamers converted to DCC yet, so I put it in the middle of my 'Aizu Renewal' set. Apart from grotty wheels and tracks, the sound is great.
DCC “Directional” Lighting without a Decoder
So, you have a 16-Car, 12-Car, 8-Car, 6-Car or 3-Car consist and you want to get the tail/head lights functioning correctly? Of course, you've already installed the expensive decoder in the engine car of the consist and if this is anything like all of the Japanese models I've dealt with, then it's somewhere in the middle and getting the power to the headlights is not really an option.
Ok, So companies like Kato have created smaller, feature-less decoders specifically for headlight and taillights in end cars... these are still the best option... the advantage to what I'm about to show you is that the lights will switch between backwards and forwards.
Anyway, if you can't, or are morally obliged not to, install the end-car decoders then you can cheat and install an AC/DC rectifier diode to 'fix' the direction of the train (and lights).
This, of course, means that the train you are going to install this into should really be only every traveling in one direction 'prototypically'. You'll be able to swap the end cars when you want the train to travel in the opposite direction, but this could be tedious and so it is entirely recommended this method only be used for consists where you intend on running them in one direction.
Micro Ace 6-Car "あいづ" KIHA 485系
So, as you may have recently seen, I installed a decoder in my 6-Car "あいづ" KIHA 485系。 The engine car was number 3 of 6, so couldn't really get any further into the center... which is a good thing as it means it's nearly pushing as much as it has to pull.
So, I decided as I'd got it at a bargain price, that I wasn't going to fork out too much to make it DCC. I had the decoder in the engine car and wanted the lights to not 'buzz' and function correctly. I intended on having it running in one direction most of the time and could handle swapping the end cars if I wanted it to go the other way.
What this meant is that I would get an AC->DC Rectifier (0.84c at the local electronics store) to convert the AC voltage off the tracks to DC.
Once in DC voltage the polarity would be fixed... even if the car was swapped around on the rails.
Right, so I removed the old lighting circuit board and bent the pins up that connected with the power rails... I then extended the AC side of the rectifier and pushed the pins into the area where the old contacts used to touch the power rails.
I then soldered up the DC output to the circuit board and threw it on the tracks to test.
Ok, this worked well... the lights even stayed on constantly after a bit of a wheel clean. Unfortunately, you now cannot 'shutdown' the train in a siding without cutting the power. The other issue now was that the rear car would have the 'Forward Lights' on as well if wired up directly... I therefore had to reverse the wiring after the DC output. I used my 0.25mm 'winding wire' for this.
And then a test...
And that was it... the train was DCC'd and ready to roll... It worked perfectly after this as well.
Twilight Express
I then quickly slapped a Rectifier in my Twilight Express end car and disabled the lighting in the car that sits right next to the engine.
To my surprise... a 12v BULB!... This must been an older set as Martjin had previously mentioned.
...and that was a wrap... yes, it's a mighty cop-out... and those who wish to have functional/switchable head/tail lights should not do this, but it does work and I must admit, does the job for my kinda running (Full Steam Ahead!)
Micro Ace 485 Series “あいづ” 6-Car Decoder Install
I found this for sale on eBay and, although it's JR East, I decided I could do with another 6-Car set.

Being my first Micro Ace product, I was extremely impressed with the level of detail. I was also extremely impressed with the electronics on the inside and the way everything just snaps together... of course, this is the same with the greater majority of Japanese model railway products... but this 6-Car set seemed much easier to pull apart.
Once apart, it was obvious that the decoder install was going to be very easy... The motor contacts could easily be separated and the power rails were made of copper... solderable!
After the copper wire was on.. the wire was lead back up alongside the copper rails to the decoder... wires were also soldered onto the rails to provide power. Finally, the decoder was installed.
Right... lighting... as per any large consist... there is usually a considerable length to the end cars for directional lighting... this usually means that people should install separate decoders in the end cars (high price!) or run wires throughout the cars (ugly!)... so instead, I decided to convert the AC current to DC and force the lights to be in specific directions...
But you'll see that in my next post!
DCC Booster Complete
Ladies and Gentlemen,
I am proud to finally announce that the Booster has been completed and tested.
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The final design incorporates the following features:
- Short Circuit Protection with a ~6sec timeout when short detected.
- Two segments per booster rated at 2-3Amp each.
- These can be combined for a total output of ~5Amp.
- Status LEDs to indicate power output on each segment and also overload/short detection on each segment.
- Second Serial Port (DB9) on the rear panel to allow data connection to another booster.
A typical setup of the Booster would be as follows:
The Booster shown above was built in a readily-available Project Box and the next one built will probably not use the same model. I'll be going to the store on the weekend to see exactly what is available as the box used is a little larger than what is really required.
Either way, if you still wanted one of these, now is the time to contact me.
Final PCB Board Complete!
Well, Silver Circuits manufactured and delivered my PCB much much quicker than expected and I'm not complaining!
And, last night, after a rush of construction... I couldn't get the board to work... The 'trip' sensors were permanently active! After a 30 minute stare at the circuit design today I'd realised I'd viewed an older circuit schematic when designing the PCB and had put the inputs to the LM339 the wrong way around!
After a quick test to correct this I had the booster operational.
Unfortunately this now means that all boards in this initial run are defective, but I have devised a way to correct the issue without too much hacking. A small veroboard piggy-backed on has allowed me to correct the inputs to the IC.
I was very much relieved once it was all operational. I now need to get the final components (you can see a dodgy-hack of resistors wired on) and the heatsinks in place.
Then I'll find a neater box to mount it all in and all should be set to go.

Yass Junction Diary