The TCS literature tells the installer to set CV182 = 2 on TCS
decoders. I called TCS and talked with JD about that. TCS has
a “stop on DC” mode enabled by default. That is, if a TCS
decoder sees no DCC waveform, but has power to run, it
assumes that it is on a DC section and will stop. Well, that’s
exactly what it will see with track power dropout and a KA
module connected. Setting CV182 will override that condition
for TCS decoders. JD confirmed that KA modules have been
used on almost every sort of decoder with no ill effects. CV
changes were only needed on decoders made by TCS.
There have been reports of the KA2 units taking so long
to charge up (several minutes) that they would prevent
the decoder to which they were attached from being pro-
grammed on the programming track. Either program on the
main (remember, no read back on the main) or disconnect
one wire of the KA unit when programming. I have had no
problems reading from, or writing to the RS27 shown in the
video with the KA2 connected with my PowerCab.
What’s in one of these modules? The heart is a bunch of
Super Caps, as I discussed in my December 2012 column
. They are low voltage, requiring about five to
make up DCC track voltage. The module also has the neces-
sary electronics to prevent over-voltage from damaging the
capacitors. They will not stand being hooked up backwards,
so be watchful with your wire colors.
Multiple KA modules can be connected in parallel for even
greater storage capacity.
The only caveat I’ve seen is most important to large-scale
users. Although they will stand any input voltage allowable
in the NMRA standard, their output voltage when supplying
power to the decoder will be about 14 volts, maximum. So, if
you are using a KA on a layout with the track voltage set for
