@Hudson J1e posted:Ted, thank you for trying to explain this. I clicked on your link and read it several times but I am still having trouble fully understanding it. I also read some other information on digital signals but they weren't a whole lot of help. I am not scientist nor an engineer but I would really like to understand how this works.
Okay, I get that the voltage never goes below 0 volts. Does the booster send the signal down one rail and use the other rail for a return or does the booster alternate sending the signal between rail A and rail B? If it does alternate the signal between rail A and rail B at what point in time does it switch rails? Can this be seen on the graph?
"The track voltage has phase, one rail is always the inverse of the other." What exactly does this statement mean?
Anther thing I found confusing was these two statements at the bottom of the page from your link:
"The 0V reference point is the chassis of the booster."
"The output of the booster is floating, as there is no fixed reference point such as a chassis ground for zero volts."
They seem to contradict one another.
During my research I found this Marklin forum where guys were talking about the same thing we are talking abut here.
https://www.marklin-users.net/...log-on-DCC-Mea-Cupla
Doesn't add much to the conversation but I thought it was interesting to know that we weren't the only ones discussing this.
I would recommend the DCC Wiki for further reading, and the NMRA DCC standards (however, they are complicated and hard to understand). You can also learn quite a bit by reading the manuals of various manufacturers. Also, I don't believe Marklin is fully NMRA compliant, they may be, but I know in the past their systems were had some proprietary changes that weren't, now they might be. Some of the other European manufacturers also have multiple modes, some that are fully DCC NRMA compliant and some that aren't. I would also look at JMRI.org, they make great FREE software to run trains using computers. I personally have JMRI running on a Windows Laptop with a connection via USB to my NCE system, and I also have JMRI running a a small Raspberry PI 4 computer using a home built DCC++EX DCC system. DCC++EX is a another wonderful way to control trains using DCC, and very inexpensive. With both of those systems you can use free phone or tablet software to control your trains with DCC. Maybe that was a bit of information overload, sorry about that. :-)
The main reason I like DCC is it is the defacto Standard, every DCC decoder I have from about 8 or so manufacturers has worked with my 3-4 different DCC systems I've used over the last 15 years, including some non Standard not fully compliant decoders like LGB MTS systems. I don't like that Lionel, MTH, and other manufacturers keep trying to re-invent and re-do digital train control with their own system, and lock you in. I do like that MTH was forward-thinking enough to allow full DCC compatibility! I like the fact that with DCC I can use the same system right now on any N, HO, O 3-rail, and G scale locos I use that have decoders! I also have some 2 Rail O engines, track, and have setup a layout a while ago. I just purchased some more 2 Rail O scale engines and cars, and I like that I can take the same $160 fully featured DCC Soundtrax Tsunami2 decoders I just installed in 3 of my G scale engines into those O scale engines, and could also put them in 3 rail if I so choose. It all just works! One time I had a multi-scale Christmas layout with N, HO, O, and G scale loops of track, I used the same DCC system for all 3 loops of N, HO, and G scale. I just used different addresses on the LOCOs, turned the voltage down to about 14VDC (didn't need high voltage for my G locos if I'm not running them fast), and ran all 3 on the same controller and booster! That is exactly why DCC is so good, it can run anything in any scale if it follows the standard. IMHO ALL Command systems should be DCC compatible.
Ted
