SC-2 problems

Try running an earth ground wire around the SC-2 lineup, they receive the over-the-air TMCC signal.

Will do. I'll let you know.

GRJ I tried a ground wire over the SC-2's. No change in operation. Tried a second cab-1 thinking my original might be the problem. Again, no change in operation. Watching the base station I see the red indicator flickers when I push a button on the cab-1 controller. So at least the controller is working. When I get the chance, I'll try to take a picture of the setup under the layout. Might be helpful. Also, I run both TMCC and conventional with a TPC 400.

I connected the track power to power the sc-2s. Having the sc-2 common connected to the outside rail just like an engine made the sc-2s work perfectly.

And I do also have the ground wire run above them as well.

You can see the green ground wire in the duct above the SC-2s. TP400 is at top, TMCC base just below that.

I have mine all mounted regionally around the layout to the bottom side of the table all controlling turnouts in their own locality. They all work as they should

My SC-2 was acting inconsistent as well. 

I literally wrapped the bare end of some 18g stranded wire around a nearby water pipe (my layout was in the basement) and then ran that wire along the floor and ended it near the SC-2 and it corrected the problem.

When you address a switch track do you hear a sound from the SC-2 itself?

I can’t stress how much my sc-2s benefited from connecting to outside rail to com as to signal reception. My experience went from intermittent operation with long delay between route commands to reliable operations with 0.5 second timing.

You have to have the outside rail (which is the TMCC/Legacy signal) connected to common or you will have very flaky operation!

I haven’t reread the instructions but it seemed that they recommended power with those wall warts. No other connection unless I missed it. I finally went to essentially like  track power with the outside rail connected.

I added a wire from the ground terminal on each SC-2 to track ground.

Seem to be somewhat better but still no cigar.

Next I'm going to check the grounds from my layout wiring back to the panel.

GRJ what "common" are you referring to? Track power or overall ground?

Track outside rail was what I'm talking about.  The relay contacts for all but channel #1 is totally isolated on the SC-2, and they don't have any connection to the internal circuitry.  That being the case, refer to the picture below.  This is a shot of a SC-2 mod to float the ground of channel #1's power.  I'd connect the outside rail to the lower terminal on the power feed to the SC-2 to improve the signal.