Does anyone know the soldering points on the DCC logic board for putting a Keep Alive on a Bachmann service truck that runs on the rail?
The common power lead, blue lead and the minus logic power. Notice, there is no ground on a decoder regardless of what some say. Only plus and minus 12 to 14v I would look at the output of the full wave bridge.
Below is a good link about this issue. He does point out other areas. Shrink wrapped can be an issue.
http://www.members.optusnet.com.au/mainnorth/alive.htm
Technical info.
https://sites.google.com/site/markgurries/home/decoders/keep-alive-compatibility
Realize, stay alive is a two edge sword. The loco can continue to run even if the DCC system is shut off. Some have had a collision, run a loco into a TT pit, onto the floor, collision between two locos with some damage., etc. I have seen this discussed in a few forums. The keep alive keeps power to the decoder. No way to shut the keep alive off. The keep alive has to bleed off.
Check the second link and see how long some keep alive last. It might not happen much but the potential is there.
Rich