DCS and conventional

You can use the DCS TIU variable outputs and run conventional using the handheld to vary voltage like a transformer handle. If you're running in DCS via the variable channel, voltage needs to remain above a threshold (16 volts in m experience) for DCS to operate properly on a loop powered by that channel.

You can isolate the three loops at the switches, run them via different TIU channels, and have a DCS engine running on one loop and a conventional engine via variable voltage on another.

You cannot run an engine under DCS on the same loop with a conventional engine unless you want the conventional engine going 100. In order for the DCS engine to function properly, it will need a minimum voltage that will leave the conventional engine running high speeds.

The book you mention is the DCS Companion. Volume 3 covers most things, and the DCS WiFi Companion is the book to purchase if you plan to run via the app rather than the handheld. Either version of the book is on Amazon.

What DCS unit? A TIU has 4 channels. Yes, a DCS explorer only has 1 channel.

The book being referred to is the DCS companion. https://mthtrains.com/DCS_Companion

Depending on what exact DCS control system you have the rules are different.

TIU- again 4 channels, 2 are fixed voltage meaning the TIU does not modify the incoming voltage to the output, and then the 2 other channels are variable- meaning the TIU can modify (reduce) the voltage compared to the input or just pass through "fixed". As long as you power the logic of the TIU, the voltage inputs can be variable from a transformer meaning you can turn them on and off and vary them and the TIU stays running. Another factor at play, this can be used in passive mode, where it only is used to provide the DCS signal to the track out of each channel and is not passing any power.

The DCS explorer WIFI box unfortunately has many more limitations. It MUST have at least 12V constant power source or higher. This is because it takes time to boot up the wifi and so forth and uses the incoming power to power itself and only has one input. Thus it's near impossible to use it on a conventional track because you need constant power coming in and it does not provide a "variable" channel output. This cannot be used in passive mode.

The DCS IR commander can also be run in passive, but is extremely limited in function and also not the strongest signal output.

In general, I think most folks find trying to operate conventional and command locos on the same track simultaneously is more effort than it is worth.  Can be done, but not always intuitive and simple.

Unless the layout is fairly large, it's hard to keep the conventional and command locos far enough apart to avoid collisions for one thing.

Suggest first using one loop or two for conventional and the remaining loop(s) for command and seeing how much effort is involved vs. fun.

Also depends on the locos.  Conventional locos only respond to the voltage level on the track they are running on.  Command locos (if the command signal is present), whether DCS or TMCC/Legacy will only respond only to signals from the command system in use, regardless of voltage setting.

One potential complication is that if you try to operate a command loco (either PS2/PS3/DCS or TMCC/Legacy) in conventional mode on a layout that has the command signal present, it may not respond to the conventional voltage control,  depending on the strength of the command signal at that track location.

All in all, isolating command and conventional locos physically (using blocks,  or separate loops) from each other may prove more pleasant.

Another approach is simply using only conventional or command on the layout at any given time, which is probably the simplest approach.

@ekjeep posted:

...I also see reference to a Barry and a book he may have wrote on DCS.  Any ideas where I can get that?

Available on Amazon.  Search for "DCS Companion".  Be sure to get the 3rd edition.  Be aware that used copies are available, but often for a price that is higher than what you can get a new one for.  Also, some folks may still be selling the 1st or 2nd editions - don't get one unless it's a real bargain. 

There is also a DCS wifi guide available - 2nd edition is the latest.  But just getting started, the DCS Companion is probably sufficient for most folks.

Unfortunately, author and DCS guru Barry Broskowitz passed away over a year ago.  However, his posts regarding various DCS issues still exist on the forum.

FWIW, the DCS WiFi Companion is really the latest information and includes most or all of the information that's in the DCS Companion.  Before he passed, Barry had stated he would no longer be updating the DCS Companion but rather just continuing with the DCS WiFi Companion.

If you get a killer deal on the DCS Companion 3rd Ed. that's OK, but if you're paying retail, go for the DCS WiFi Companion 2nd Ed.

Thank you all so much for the awesome guidance.  Will share with my builder and come back with any questions.   Thank you!