Running in transitional mode

If the sound boards are receiving the serial data from the TMCC receiver, they will not respond to track offsets for horn/bell.  If they're stand-alone conventional sound boards, I'm not sure what you're doing here.  If they're running in TMCC, how is the DC offset getting onto the rails?

Worked out the solution this evening.  It is not possible to derive a dc offset from a tmcc board.  It is possible, however to run a tmcc engine thru a TPC which is set for the M or conventional mode. The Tmcc engine speed will be restricted by the throttle level set for the TPC.  To run the engine, press m set on cab 1.  With engine on track, select tr 1 or whatever number your TPC is assigned. Spin the throttle until the lighted cars or engine headlight look right.  At this point, you can sound the conventional bell ,whistle, or horn.  Address your engine and pull out. Now the engine is under command control. To control engine functions  and use conventional sounds, toggle between the tr and eng buttons on the cab. Sounds complicated, but you need to be running in this mode to run conventional and TMCC engines on the same track. Having the conventional sounds work is a bonus. One

downside is that all conventional engines on the track will sound off together. I am investigating a couple of add on boards to trigger the offset from the TMCC board.  Will post what I find out.

The only way I know of to trigger a whistle or bell through the TMCC receiver is to decode the serial data that's intended to go to the RailSounds board.  I've done some work on this, but I don't have a working prototype yet.  I'm using the Arduino microprocessor boards.

Two modes are pretty much separate.  They're supposed to be.  A command equipped engine will "listen" for the carrier frequency on power up.  If it detects it, it goes into command mode.  If it doesn't, it goes into conventional.  In command mode, DC offsets are pretty much ignored.  If this wasn't the case, all engines would sound off horn or bell when you triggered an offset.  The TPC can be used to run a command equipped engine in conventional mode but only if you a) power up the equipment out of sequence or b) disconnect the wire from the command base to the track at the command base side.  When you do the latter there will be no track signal and ALL engines will run in conventional.  If you use the power up out of sequence method this only works until you interrupt power to the track.  Once you do that and power is restored the command engine will see the carrier and run in command mode.

I'm still trying to figure out why you would want to try and trigger sound effects on a command engine with conventional controls when you obviously have the command base up and running to run the conventional engines?  If you don't want to trigger the horn or bell, don' touch those buttons?

Chuck, I think he still has a conventional whistle/bell board in the locomotive, it's not connected to the TMCC serial stream.  At least that's what I'm getting from the thread.

OK, so we have a command engine without railsounds?  And this is to get around installing a circuit to allow the TMMC controller board to do the dirty work?  I think I've seen this on the ERR instructions that you can adapt a PW whistle/horn to work with a command board?

Sadly, that doesn't work for the Cruise Commander, but there is a 5V logic output that comes from the AC or DC Commander boards that you can modify the standard sound boards to toot the horn.  You don't have any capability for the bell with this mod.

Truthfully, it would be nice to know what boards are actually in there locomotives.

Or get a signal sounds board?  I think some of those are still available from parts suppliers for $30-$35.

Ok guys.  Everybody is assuming I am running factory equipped TMCC engines. Not so!  These engines are post war units I have installed LCRU boards in. After buying one ACDC Commander and $50 sound commander board, I decided to purchase several sound commanders to install with my LCRU boards. Never got a chance to try them. When I tried to order, ERR said the boards were no longer available.  Reason given was obsolete parts.  More probable truth is Lionel had purchased ERR and stopped them from selling a system which was very competitive with Railsounds. Bottom line is, I want to find a way to use the serial output from the LCRU to trigger something which will produce the dc offset to necessary to sound a postwar horn or whistle.

   I bought two good, simple,sound units from QSI several years ago.  The units are replacements for post war whistles/horns and are installed with two wires to track power and ground. The units are called Hooters and Tooters, and The DC offset triggers these units.  Nice sound units , but only usable in a command environment

in the manner described in my original post.

  I do plan do do a search for the boards chuck suggested.

On one of my back burners, I am looking at decoding the RailSounds serial data stream and being able to trigger sounds and other actions using a microprocessor, in my case the Arduino.  When I get a working model, you'll hear about it here.

I wonder if the serial code for horn and bell is the same as the Base to computer code?

The early Conventional RailSounds tenders have a small mother board that accepts the Power Supply and RS or SS board.  Would be an easy mod to add that with a Command RS board.  Expensive but easy.  G

There is even a small and inexpensive TMCC receiver that would do the trick.  However, the object of the exercise is to do more than create a $100+ solution to audio, but rather be able to use all the TMCC commands to activate a number of functions.  For instance, for a steamer, the front coupler is normally not used, but if you capture that code going out the serial data, you can trigger any function you desire with it.

The code appears to match the documented TMCC commands, but they're transmitted at an odd rate, around 3,000 BPS.

I am confused.  IF you have the TMCC receiver, you have the output to control all those features.  The issue is driving conventional sound boards.

Chuck,  The ERR solution is interesting. They are not using the serial data to control conventional sound.   It applies to the AC/DC commander.  Looks like what they did is turned off the 5VDC at pin 3 of the 4 pin RS jumper.  When a horn/or whistle is signaled by TMCC the AC/DC Commander turns on the 5VDC temporarily.  So pin 3 can be connected to a Lionel Horn or whistle electronic board where the offset would be detected, and the 5VDC signal activates the conventional sound.  They show a device you can build to allow that 5VDC to activate a PW Relay using an optical coupler.  Prevents the 5VDC regulator from being overloaded by the PW relay.  Neat addition.

For a R2LC or LCRU that 5VDC signal is always present.  So it won't be effective.  G

The DC signal is also not available on the Cruise Commander, which is a shame.

I'm not sure why you're confused, what is confusing you?  I want to remote control more than sounds, what's so hard about that?

So you want to build your own R2LC?  I thought you were originally talking about a translator to read the Serial data for horn and bell and allow it to activate conventional sound units.  The R2LC already does the coupler, lights, smoke.  To operate additional items would require additional serial data codes too wouldn't it?  Some new code to turn on and off a marker light for example.  How would you get the CAB-1 to produce those codes?  G

No, I'm not building my own R2LC.  I'm indeed decoding the serial stream that normally goes to the RailSounds board.

I already stated how it would be done.  Perhaps this is a topic for another thread as I don't want to further hijack this one.