Sound on a 2-6-6-2 Mallet tank loco 1:20.3

[badlydrawnroy]

Does anybody know how to connect the chuff-sensors to a Phoenix sound board?

[James]

The easiest thing to do is use the reed switch that Phoenix Sound usually includes with the sound board.   Place the sound board in the tender and place the magnets on a tender wheel (I use three most times).  I know it is not in phase with the locomotive wheels but almost one will ever notice that.   I do this on all of my steam locomotives.  It will be a lot more effort (I mean a LOT) to do what you what to do.

James

[Greg Elmassian]

If you want to exactly sync the rate and position, you will have to work with the IR sensors, actually just one, since the Mallet exhaust is only heard from the final set of cylinders.

The exploded parts diagram has the wiring diagram too:

https://www.bachmanntrains.com/home-usa/dwg/dwgs/82894.pdf

You should be able to get recommendations on wiring from Phoenix.

Greg

[StanAmes]

It is fairly easy to hook up the phoenix sound board to a 2-6-6-2.

Connect the 1st chuff input to the locomotive Chuff Trigger 1 (J1 pin 5)  and the phoenix chuff ground to the locomotive ground (J1 pin 7)

If you want a cool effect  have a function output on your control board power a relay that is connected to the phoenix second chuff trigger and the locomotive Chuff Trigger 2 (J2 pin 2)

Note the locomotive connections on on solder pins on the side of the board.

The 2-6-6-2 is a compound mallet. This means that the steam exhaust from one set of cylinders is fed to the input of the second set of cylinders which is then exhausted up the stack.  This provided 4 chuffs per wheel revolution.

To gain maximum tractive effort the engineer can switch from compound mode to simple mode on startup.  Normally simple mode is used below 5 mph and compound mode above 7 mph.  Simple mode will provide 4 chuffs from the rear engine and 4 chuffs from the front engine going into and out of sync

Using the relay for the second chuff imput allows you to simulate this effect.

Hope this helps

Stan

[Greg Elmassian]

Stan, looking at the documentation, it appears these are an IR transmitter LED and an IR photodiode/phototransistor.

So the on/off resistance of the phototransistor works just fine with the reed switch input?

(I know that is what you just said, but confirming)


Greg

[StanAmes]

Greg

All Bachmann Spectrum locomotives post the K27 have the required electronics to connect directly to all the popular sound boards chuff inputs.

The 2-6-6-2 has two chuff outputs. One for the front engine and one for the rear  Of you only want 4 chuffs per revolution only connect one of the outputs to the sound board.  If your board has 2 chuff inputs you can connect one output to each input and get two sets of 4 chuffs that are out of phase

Stan


Stan