Lionel 691-ISND-GST Board Interface

gunrunnerjohnOGR Forum Member SUPPORTING MEMBERDIGITAL SUBSCRIBER

I'm trying to stick this little board into a conventional tender and use a reed switch to generate the chuff for it. For some reason, I can't get a good chuff from the board, it worked with the hall effect sensor, but that doesn't really fit on this tender, not to mention I don't have the axle magnet.

There are three wires to the hall effect sensor, 3.3V, GND, and CHUFF. These seems pretty simple, you toggle the chuff between GND and 3.3V. No matter if I pull it to the 3.3V with a 1k resistor or tie it to GND with the 1K resistor and toggle to the other value, I don't get consistent chuffs. I get some really odd chime effect at times, really odd. I even tried a .1uf cap across the pull-up resistor with no change.

I've done the same mod a coupler of times with the RTR RailSounds board, what's different about the hall effect input on this one?

4/13/1412:53 PM

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rrmanOGR Forum Member

Hi John,

Google the hall effect part number to see if analog or digital. Possible that type might matter in how board operates. Check how hall effect vendor hooks up part and check how the reed switch emulates the hall effect on/off. Will assume reed switch contacts are solid 0 ohms when closed. Is it possible that hall effect circuitry has to be closed normally but opens momentarily to chuff, rather than opposite of close momentarily and open normally?

Maybe try hooking up hall effect sensor and wave magnet near it to see if normal chuff occurs. Put scope on sensor output and see what waveform looks like ie on/off or varying output.

Now have me curious.

4/14/142:38 PM

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gunrunnerjohnOGR Forum Member SUPPORTING MEMBERDIGITAL SUBSCRIBER

I was trying to avoid doing it the hard way, but that may be the only way I'll get it working.

4/14/143:04 PM

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NortonOGR Forum Member

If you have room for the puff n chuff circuit that should work. Converts open-short to gnd and VCC.

Pete

4/14/143:41 PM

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GGGOGR Forum Member

Don't you just put the 3.3V to the chuff via the reed switch? When switch closes the chuff signal is present? Are there any other components on the hall sensor? G

4/15/147:18 PM

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gunrunnerjohnOGR Forum Member SUPPORTING MEMBERDIGITAL SUBSCRIBER

It's just the hall effect sensor on the board, this one. I'd like to try just putting this onto it and stimulate it with a magnet.

I don't know the pinouts of the little board, and I don't have the original harness that went to the Trainsounds board, it was lopped off and that connector I don't have. I have the little connectors, so I made my own for the board, now I'd just like to get it working.

My board has a connector with a yellow, green, and blue wire. I could guess at which is the power and ground, but I'd probably only get one guess. I do know where they are on the Trainsounds board as they're marked.

I tried pulling the chuff to ground, pulling it up to 3.3V, and I even put a resistor to ground and the chuff, then to 3.3V and the chuff and pulled it the other way. I get chuffs interspersed with the real obnoxious sound that appears to be a garbled bell, but it's hard to tell.

I also put a cap from the chuff to ground, a .1 didn't help, and a 1.0uf NP slowed the chuff response WAY down, but did kill off the odd garbled bell sound.