Question can Legacy and DDC be run at the same time on the same track?

From what I have read I do not think DCC can be used at the same time on the same track with either Legacy or DCS. I believe DCC will work on the same track, but not at the same time with the others. I am not a DCC expert by any means, but I have been thinking about adding DCC to my layout someday. DCS and Legacy do work just fine together, I have both running on my layout and they work very well together. 

I would say no, but I have never tried it.  DCC track power is really a PWM square wave.  I'm guessing that would drive the DCS signal batty!

His question was not about DCS and dcc which according o MTH are not compatible eth each other but with dcc and legacy. I would say that you most likely would not have any issues as  dcc transmits it's commands by modulating the power on the tracks and legacy essentially uses the track as a radio antenna. Try it n see, I bet it does work

Truthfully, I think the square waves on the track won't do the TMCC track signal any good either.  I would expect pretty poor performance.

your prolly right John, as the other half of the square wave form switches to the other rail the legacy signals will most likely screw it up and in all actuality neither system may work at all. Im gonna try it on my test track. You think it'll screw up either system

It shouldn't damage the systems, but I'd be amazed if it runs.

What's the legacy carrier signal look like when it's not sending?

It's a continuous 455khz signal (nominally).  It shifts a few khz as it sends data.  It's always send out null data when it has nothing to say.  It's about 3-6 volts P-P on the 'scope.

Yeah, I'd be surprised if either work

I routinely test our flyer locos with DCC capability on the same track as legacy locos without DCC capability - with DCC power and signal on the track and a command base active. There are limitations with the functions (ie electrocouplers get stuck on) if Triac controlled on DCC track power, and limitations if the locos have older electronics(ie whistle or bell may get stuck on).   

However, The signals don't interfere with each other.   Without knowing more about the OP product, hard to say what may work or not work. 

gunrunner, every time i am amazed by your knowledge of this stuff, you raise the bar a bit more. i'm impressed and that doesn't happen very often.  Thank you for sharing your wisdom, despite doing this stuff for a livelihood. This is a heart felt compliment!  Thank you. so much.

Ok, so both systems work together and I was able to control both locos however, both locos had some serious feedback squeal

SantaFeFan posted:

I routinely test our flyer locos with DCC capability on the same track as legacy locos without DCC capability - with DCC power and signal on the track and a command base active. There are limitations with the functions (ie electrocouplers get stuck on) if Triac controlled on DCC track power, and limitations if the locos have older electronics(ie whistle or bell may get stuck on).   

However, The signals don't interfere with each other.   Without knowing more about the OP product, hard to say what may work or not work. 

Very interesting Jon, I would have expected more signal issues.  I guess you can say they "sort of work".

Thanks every one for your advice. It would just be for running Legacy and DCC (no DCS) . 

But it doesn't sound like it is doable especially if electro coupler would not work.

I am currently just running Lionchief Plus but looking at options for when I get a Legacy system and to continue use my existing DCC system