ErrCo Sound Converter?

I just purchased one of these boards. I think it will also work with only certain command boards?

I actually beta tested this board, and I've tried it in a couple of different scenarios.

The issue here is that it doesn't vary the AC voltage as the PS/1 board expects to change the primer mover speed (or chuff for steamers).  It simply passes the AC through and imparts the DC +/- bias based on the command inputs of horn or bell.  This works great for many common conventional horn/bell boards or something like the Polar Express announcement coach.  That was one of the target projects when this board was originally conceived.  The output section of the schematic is below, the red arrows denote the triggers for whistle and bell outputs from the decoder.  As you can see, the sound card is powered by the AC coming through the two regulators, that's how the DC offset is inserted into the AC stream.  From my tests, these are good for several hundred ma of power without any heatsink, and you should be able to do quite a bit more if you bolt them to a heatsink or the chassis.

So I take it there is more to the circuit to translate a TMCC signal and convert it to the DC offset to trigger the sound function?  G

Yep, it receives the serial data and triggers the whistle/bell offsets on those outputs.  It also has some LED outputs that are pre-programmed.  Two are ditch lights, they flash for the whistle/horn as expected.  The other one is a variable intensity cab light. 

I want to use this to upgrade an old issue MTH UP Veranda Turbine which is why I want to use the original sound board.  Since the turbine would essentially run at full speed anyway I would only need to trigger the horn and bell on the proto 1 board. So, as long as I can get a continuous turbine whine sound using this board that would work for me.

What do you think?  Should it work in my situation?

Thanks,

Fred

Well, I haven't tried it.  However, on boards with prime mover sounds, when they see full throttle, they do indeed run at maximum RPM, so it theory it would work.  It's cheap enough to give it a go...

This might be the ticket for my starter set 0-8-0. The trainsounds are fine with me but would like to add TMCC and the Cruise Lite and sound converter would be perfect.

Pete

That might work, how does the chuffing work?  Is that triggered by a wheel sensor?  If so, you can probably leave that in place, and you'd get the whistle & bell under command control.  You can also have ditch lights, just the ticket for that 0-8-0!