Lionel 6-19833 RSII 2426 Tender - chuff rate adjustment

I do not know of any way to keep it self contained in the tender.  To get 1 chuff per every other wheel revolution on the tender would take some serious engineering. Probably your best bet for a realistic answer is going to be (you never stated what postwar engine you have), is mount a Cherry switch next to the smoke unit and use the smoke piston arm as a source to trigger the Cherry switch, Going to take a little engineering, but I envision it as do-able. Another possibility is replace the pellet generator with a liquid generator from the MPC era. And the matching piston for the make and break contacts. The run wires to a 2 prong male/female socket to the tender.   

@Chuck Sartor posted:

I do not know of any way to keep it self contained in the tender.  To get 1 chuff per every other wheel revolution on the tender would take some serious engineering. Probably your best bet for a realistic answer is going to be (you never stated what postwar engine you have), is mount a Cherry switch next to the smoke unit and use the smoke piston arm as a source to trigger the Cherry switch, Going to take a little engineering, but I envision it as do-able. Another possibility is replace the pellet generator with a liquid generator from the MPC era. And the matching piston for the make and break contacts. The run wires to a 2 prong male/female socket to the tender.   

Mostly going to run behind a 2046 or 736. Th goal is to have it work stand alone so the engine is never touched and it can work with any postwar steam 

Chuck is spot-on.

One chuff per wheel revolution can be done, but would involve a micro-switch or reed switch in the locomotive along with a tether to the tender.

Because of the smaller tender wheels, anything timed to those (whether using the built-in hall-effect sensor or an add-on read switch) gives the approximate equivalent of two chuffs per revolution when compared to the loco. I don't see why you couldn't have a separate circuit devised that would essentially ignore every other chuff activation, but that's not exactly practical.

TRW

It would be a simple circuit, but it would have to be designed and of course built.  I can't imagine too many applications for slowing the chuffs down.

@gunrunnerjohn posted:

It would be a simple circuit, but it would have to be designed and of course built.  I can't imagine too many applications for slowing the chuffs down.

So there’s no adjustment pot or no way to crack into the sound chip then? That chuff rate must be programmed and built into the sound chip right?

Why else would the chuff rate be 1 chuff per two magnet turns and now 1 chuff per 1 magnet turn with the Vanderbilt Hudson board that is now in there?

 

@PaperTRW posted:

Chuck is spot-on.

One chuff per wheel revolution can be done, but would involve a micro-switch or reed switch in the locomotive along with a tether to the tender.

Because of the smaller tender wheels, anything timed to those (whether using the built-in hall-effect sensor or an add-on read switch) gives the approximate equivalent of two chuffs per revolution when compared to the loco. I don't see why you couldn't have a separate circuit devised that would essentially ignore every other chuff activation, but that's not exactly practical.

TRW

interesting point. Any idea what kind of circuit would “ignore” every other rotation like that?

Look into a counter circuit. They are simple so you won’t have an adjustment. But when it counts two revs it could pass on the chuff signal.

Just a simple J-K flip-flop will divide by two, just that you were looking for in this application.

@gunrunnerjohn posted:

Just a simple J-K flip-flop will divide by two, just that you were looking for in this application.

looks awesome. Very clever! where can I find / what would you recommend to be - the appropriate flip flop device you show in your diagram here?

*By the way - I installed your YLB device in this tender too and that thing is OUTSTANDING!! 

 

My goodness, if you just go to Digikey and search for a J-K Flip Flop, you'll find hundreds.

How about the SN74HC112N  for 50 cents?  Obviously, you need a source of 5V to power it.

@gunrunnerjohn posted:

My goodness, if you just go to Digikey and search for a J-K Flip Flop, you'll find hundreds.

How about the SN74HC112N  for 50 cents?  Obviously, you need a source of 5V to power it.

That looks like an old processor chip. I have no receptacle to plug it into and power that with and connect the circuits. Maybe I just don’t understand.

Sorry I’m just not that familiar with some of this stuff yet.

Well, yes, you have to provide the wiring on something like a perf board at least.  It sounds like you're looking for a turn-key solution that doesn't involve any soldering.

After much consideration - I’ve abandoned the idea of trying to fool around with the chuff rate in the tender and decided to make it switchable between the onboard wheel (approx 2 chuffs per average driver rotation) and possibly add a tether connection to go with specific p/w locos that I might add a (removable) reed switch and magnet to in order to get proper synced chuff at whatever rate I want.

Thank you everyone for your contributions of great ideas and input.