FM conversion again, different problem

The sound board has connections to its' speaker, a hot and ground connection.

Thats your answer. There is no serial connection between the LCRU and the sound board. Not knowing what sound board you have, I would say it probably is for conventional only.

Bill

I know the board is conventional only.  My question is, why does the sound board respond just like a post war unit until the LCRU is addressed?  What effect would the lcru have on a dc offset delivered to the engine to trigger the sound board.

  Another sound topic;  In a command environment, could the ERR accessory board be used to trigger a post war sound unit?

 I know the board is conventional only.  My question is, why does the sound board respond just like a post war unit until the LCRU is addressed? 

  You are addressing the engine. The LCRU is listening but it is not connected to the sound board, so no sound.

Bill

I think what Bill is saying is when you address the engine the whistle command gets sent with the engine address attached to it but when you are not addressing the engine the general whistle command gets sent. This gets picked up by the TPC which sends the whistle offset to the track. To test this you would need a transformer with a whistle button. Get the engine running in TMCC mode and press the whistle button on the transformer and the whistle should blow. I think with the TPC you could address the track number the TPC is controlling and then blow the whistle also.

Ron

PROBLEM SOLVED!!  It should have been obvious.  When the power is supplied thru a TPC in M (conventional) mode, the TPC will provide a DC offset when the cab 1 whistle/horn, or bell button is pressed.  When the engine is addressed, the CAB1 sends a digital command for sound.  To sound the horn with the LCRU operating the engine, the trick is to toggle to track #, sound horn, than toggle back to engine #

to regain engine control.  A little clumsy, but workable.  My next move will be to contact ERR to ask whether their Accessory board can be made to sound the conventional horn.  Thanks to everybody who responded!  You were all correct, but I wasn't recognizing the relationship between the Engine and track control functions on the CAB.

That's exactly what I said. Glad you got it working! 

Ron

My memory is a little fuzzy, but if you read the ERR manuals, and look at the cool tips part of their website, it's explained therein.

I don't know that the accessory board will directly sound a horn, but you can kludge one up to make that happen.  I think I'd be looking at a relay to inject the DC offset when triggered by an accessory board output.

In my stash of "bought just in case items" I found 2 TAS whistle controllers to trigger post war horns/whistles thru TMCC.  The question now is, can I trigger the TAS board from the LCRU boards I am using for upgrades?  The TAS board has a red and black output to go to the horn/whistle, but the schematic calls for connection to the R2LC

which I think is a component of later TMCC systems.  What I need are connections from the TAS board to AC Hot (pins 1&2 on R2LC), AC Ground (pins 3&4 on R2LC), +5v DC (pins 19&20 on R2LC), and lastly, serial output (pin 24 onR2LC)  My question is are these connections all available on the LCRU, and where would I tap each one?

If you have a TMCC serial output from the LCRU board, it should be the same as connecting it to an R2LC.  Obviously, the track power can be tapped off directly, but I don't know about the 5VDC power.  I suppose you could add a diode and regulator to generate 5V if it's not available.