If a decoder is programmed with engine number and other cv values and then stored off line will the decoder retain the settings indefinitely or will they decay after a given timeframe? Thank you
CV settings are stored in EEPROM in the controller chip and should, in absence of external influence, retain values for many years. External influences - there have been cases of decoder memory being scrambled if there is a short, or should the decoder be exposed to radiation or something. But program a decoder, pack the loco away in safe storage, then pull it out 5 years later - it should still have whatever CV settings were programmed in to it.
There is a supercapacitor on MTH Protosound 3 boards, I’m not sure which of the settings that is used to maintain, but eventually it will use up the charge and whatever settings it was saving will be lost.
–Randy