Trouble wiring Quantum Engineer to MRC 280 (dual throttle)

Having problems with this. According to instructions, you wire each of the two red wires of the Quantum to the DC portion of the power pack, and then run the two black wires to each side of the track. But this is more complicated with the dual throttle power pack. I spliced in two wires to each of the red ones (to turn each of the red wires into two), so that one could go to each to the left and right terminals for each of the two throttles (total of four wires). Then I ran one of the black Quantum wires to the track terminal and the other I ran to the Atlas Selector, as I have several blocks on the railroad. But now the trains only run forward (won’t reverse) and either throttle controls the same thing…the power pack is not distinguishing the two throttles separately. What am I doing wrong? I forgot to mention that since I am still waiting for my sound-equipped loco to come in, I am just testing this with non-dcc/sound locos (Proto 1k’s to be exact).

it might have to do with the fact that both of the throttles on the tech4 are just that - two throttles, so if you hook both of them up to the same thing, whichever one has the “higher” setting will likely override the “lower” setting…

If I’m understanding what you did correctly (and the way that this is supposed to work), you will need either a second Quantum unit between the other throttle’s output and the main line, or you will need to circumvent the quantum unit with one of the throttles (for clarity, we’ll call them throttle A and throttle B)

Assuming you don’t want another Quantum unit…

  • Throttle A Positive-out should be connected to the Positive-in on the quantum unit
  • Throttle A Negative-out should be connected to the Negative-in on the Quantum unit
  • Quantum Positive-out should be connected to the “A” terminal of the Atlas Selector
  • Quantum Negative-out should be connected to the common(?) rail
  • Throttle B Positive-out should be connected to the “B” terminal of the atlas selector
  • Throttle B negative out should be connected to the common(?) rail

Exactly. You cannot connect both throttle outputs directly to the input of the QE. Just one at a time, you can use Atlas components as described above, or some DPDT switches. Or you will need a second QE, one for each throttle. If you intend to run two trains at the same time and want to control sounds on both of them, then the only option is two QE’s.

–Randy