Help needed for dcc decoder that supports DC 3-12V outputs

[Hornbyguy1707822480]

Greetings all

I have plans on making a dcc loco sound loco with smoke with a mist maker.

The mist maker makes nice realistic smoke with just a couple of drops of water it takes 3 to 12 volts but it isn't necessary going all the way 12 volts.

But I don't know a dcc sound decoder that can power this I'm thinking of something abit cheap as I'm on a budget

thanks

[RB51]

Hi Yusuf, I have edited your post slightly to make it more readable, I hope you don’t mind. Also, this forum does not require you to put spaces between paragraphs.

Your image suggests you might be considering making your smoke unit on a commercial basis, if so please be aware that selling is not permitted on this forum. I appreciate you may have used a stock image though.

Good luck with your project.

R-

[96RAF]

Most decoders have hardware function outputs at 12-14v potential @100mA but some 21-pin MTC decoders can also have logic level outputs at 3v potential @few mA to drive additional electronic circuits built into the loco.

I don’t know of any decoder with a graduated function output., so you would either have to build the supporting electronics for that yourself or you could use a second decoder and use the motor output (0-12v PWM).

You are obviously aware that TRS trains uses these misting devices as does Hornby for their new steam equipped locos. The clever bit is the driver electronics which synchronises the chuff rate and volume of steam to match the sound decoder triggering the chuffs.

You could simply connect one of these misters to produce constant smoke in a similar fashion to the oil burning smoke unit but it would similarly unrealistic.

You state that a few drops of water is all that is needed to produce the effect, but the afore mentioned systems incorporate a custom fit water tank that generally runs steam for 20-30 minutes.

Good luck with your venture.

[Jupiter 1707822591]

How much current do these things draw ?

[96RAF]

@Jupiter

Typical of the breed for these devices. The driver board needs extensive miniaturisation to use in a loco as well as synchronising with a sound decoder and provision of a water tank..

[Hornbyguy1707822480]

Hi Yusuf, I have edited your post slightly to make it more readable, I hope you don’t mind. Also, this forum does not require you to put spaces between paragraphs.

Your image suggests you might be considering making your smoke unit on a commercial basis, if so please be aware that selling is not permitted on this forum. I appreciate you may have used a stock image though.

Good luck with your project.

R-

Thanks I'm fine with that

[Hornbyguy1707822480]

Most decoders have hardware function outputs at 12-14v potential @100mA but some 21-pin MTC decoders can also have logic level outputs at 3v potential @few mA to drive additional electronic circuits built into the loco.

I don’t know of any decoder with a graduated function output., so you would either have to build the supporting electronics for that yourself or you could use a second decoder and use the motor output (0-12v PWM).

You are obviously aware that TRS trains uses these misting devices as does Hornby for their new steam equipped locos. The clever bit is the driver electronics which synchronises the chuff rate and volume of steam to match the sound decoder triggering the chuffs.

You could simply connect one of these misters to produce constant smoke in a similar fashion to the oil burning smoke unit but it would similarly unrealistic.

You state that a few drops of water is all that is needed to produce the effect, but the afore mentioned systems incorporate a custom fit water tank that generally runs steam for 20-30 minutes.

Good luck with your venture.

Yes I'm aware that trs trains make this but didn't knew hormny dose too I'm am gonna make a small compartment for the water

 

 

But I do want to use a decoder with sound if possible but I'm on a budget and TTS decoders won't so the Job so I may I have just connect it to the pick-ups as a test

 

 

Mod note - please don’t use the blue button to reply, use the three dot context menu for a quoted reply else just a plain reply in the box at bottom of page.

[96RAF]

It was announced in their 2022 range so it has been known since January this year. Three locos to start with - FS, Black 5 and P2.

As stated it needs a suitable sound decoder to make it chuff, else all you will get is a constant stream of smoke like in my picture.

[Hornbyguy1707822480]

I have just buyer some and they should be in there way I'm going to try dc first and figure out if a TTS decoder can handle it

[96RAF]

If you can keep the current draw to less than 100mA then it may work but the TTS decoder does not have a pulsing function output to simulate chuffs. You will need to build a circuit to simulate chuff rate based on BEMF and throttle setting as TTS does internally. It may be possible without BEMF by comparing requested speed (throttle speed step) with real speed (achieved speed step), but don’t ask me how you could do that - outwith my skill set.