Are you using an LCRU (stick-pins and hardwired) or an LCRU2 (LEOCO connectors)?

If it's the LCRU2, try reprogramming the board with a diesel code, like a "4". If your LCRU2 was previously programmed as a steam loco with wireless tether, your RailSounds board might not have recognized the inverted serial line.

If it's the LCRU, I don't think there's an easy answer.

TRW

There has to be a serial data pin on the LCRU, it was used in the 18045 Hudson, The easiest way would be to go to a AC commander....

Marty

Yes, its an early LCRU, stick pins/hard wire.  I did try a reprograming code "8" (diesel), but the Lionel reprogramming sheet specifies for an RL2C or LCRU2.  So.... looks like I need an AC commander.  Thanks TRW and Marty for your responses.

Ed

I suspect the early LCRU would need an inverter circuit for the serial data to make it compatible with the ERR board.

You'll be MUCH happier with the performance of the AC Commander, it's a good investment for such a locomotive.

I was able to use the LCRU serial signal with an ERR sound converter by adding a buffer. See the topic

ERR Sound Converter Struggles

near the end is a diagram of the circuit that I used.

Interesting, that isn't inverting the signal, it is an emitter follower to just isolate the signal going to the sound card.  So, maybe the serial data isn't inverted, but just doesn't have the drive to run the ERR board.  Based on some input from Jon Z. at Lionel, I "improved" my buffer circuit, here's the improved version.  Obviously, the colors are not really significant to the circuit operation, but when I use this circuit, I use those colors so I know what's under the heatshrink.  I've used this version in several instances where I didn't have enough drive from the serial data.

A buffer circuit just might do the trick.  I'll do a little bench test experimenting before giving up on the LCRU based on your input David and the additional info from GRJ.  Will keep you posted.

David, I used the buffer circuit you described in the ERR SOUND CONVERTER STRUGGLES post and it worked like a charm.  So, thanks to you and GRJ the ERR Railsounds is now compatible with the installed LCRU.  

Cool, glad it worked out.

This forum is a good place to share information. I have learned a lot from reading about problems and solutions. I have several LCRU's to install and it's nice to learn that with a buffer the ERR sound modules will work.