# Need help identifying decoder in old Roco BR 80



## Kapremont (Feb 13, 2011)

Hello everyone!

I’ve recently bought an old Roco (BR 80 017) from e-bay. The loco has a decoder installed but I can’t seem to get it working, it doesn’t respond to throttle, CV reads or reset.

I think that decoder is OK since loco runs fine on DC but doesn’t move when DCC signal is present (if I use zero stretching).

Looks like it was a part of starter set and came with decoder preinstalled (it’s plugged into NEM 652 8-pin socket). Quick google search revealed that Roco used decoders from other manufacturers but I couldn’t find a match of any pictures  Main chip is obscured by a plastic thing that keeps the decoder in place and that doesn’t help with identification.

I’m using a DIY command station / booster that works fine with Digitrax decoders but it doesn’t support all programming modes (for now). If I’d know what decoder expects I could modify command station code to accommodate that.

Please see the attached pictures. Hope that someone could recognize it!

Thanks for looking!


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## NIMT (Jan 6, 2011)

I've been doing decoder installs for along time and I'm thinking it's a LENZ decoder, possibly only a 2 digit address. Old technology.
Just because it works in dc it might still be dead. Old decoders were not always dual mode (DC / DCC) operational.
Does your system have any ability to read the chip's CV's?
Do you know anyone else that you could have read it on their system?
You could send the chip to someone like me and have it checked and programmed for you.


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## Kapremont (Feb 13, 2011)

Sean, thank you for quick reply!

My command station can only write CVs in direct mode and read in bit-manipulation mode. None seem to work and I don’t have any universal DCC systems around. Also, my system works in 128 step mode, maybe old Lenz only support 14 steps? Do you know this particular Lenz model? Perhaps it only supports certain programming/reading modes?

Sending the decoder for repair is probably won’t worth the money since I can buy a new Digitrax one for less than $20. Just wanted to get it working if possible. I can tweak the command station since it’s my DIY project and main part of the hobby 

Thanks again!


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## NIMT (Jan 6, 2011)

Sorry I don't know which model it is I can tell it old by the way it's made.
I think your right in thinking it's only 14 step or possibly 28.
You would be better of replacing it with a newer chip, It would run a lot smoother.


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## gunrunnerjohn (Nov 10, 2010)

Looks like it was cobbled up in someone's basement.  I think I agree with the suggestion to install a modern encoder.


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## Kapremont (Feb 13, 2011)

Guys, thanks for suggestions! 

I’ll try 14 steps and different addressing modes before throwing this decoder out. :thumbsdown: Loco itself is quite clean and was hardly ever run.


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## Kapremont (Feb 13, 2011)

*solved (sort of)*

Well, an update to my findings, maybe it could prove useful to someone 

I managed to get decoder working in 14- speed steps mode. It accepts throttle commands on address 08, apart from that nothing seems to be functioning. It doesn’t respond to my programming attempts, no matter which write modes I try. When reading CVs it seems to respond with ack pulse (motor jerks a bit), but my hardware can’t recognize it, perhaps it’s just too short. With Digitrax decoders ack pulse is visibly longer.

Anyway, I can use the loco now! :laugh:


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