If you are just repairing, I think it ought to be easy to find a second-hand reverser unit, since a lot of people convert their old locos to digital.

There is no Märklin recommended "full digital" conversion for this loco, as far as I know. If you want to convert to digital rather than just repair, I see four options:

1. Put in a "Delta" decoder or compatible. This will not give all the digital features like acceleration/brake delay etc. and most types don't recognize digital/analog automatically.

2. Find an old Märklin C80 decoder. These are not manufactured any more but you may be able to get one anyway. It recognizes digital/analog automatically, but doesn't offer acceleration/brake delay.

3. Uhlenbrock makes a decoder for field-coil motors. I don't know if it senses the operation mode automatically. I don't even know if it can run AC at all, but somebody else in this forum can certainly answer about that.

4. Replace the field coil with a Hamo magnet, and put in a decoder for a DC motor. This alternative can quickly become very complicated, since some decoders need programming via digital equipment etc. But the result may be better than with the other methods.

Another comment on my own posting:

It seems that the new 66032 Delta Decoder automatically senses analog operation. Thus, this may be a good alternative, since it is also relatively cheap, and can be set to any of the 80 digital addresses.

Michael Mascagni

If I weren't a Mathematician, I'd be a Violinist.--Albert Einstein

Yes, the 66032 does still work with Delta after soldering the connections as do any digital decoders if you set them to the Delta codes.
However, it acts JUST like a digital decoder, so the lights on function will not work and, if you have changed the other jumper, the telex coupling system on Delta will not work.

Chris Busby
UK Marklin Digital layout builder