Tex,
What scale are you modelling?
Would love to see a closeup of how all that works. You using jumpers for the running lights too? That would be a lot of contacts.
For me, too much hard work. I'm time poor. Also, I model in N-scale so separate decoders is a logical choice.
Yes. In fact, that is how the original PCM units were from the factory. Decoder in the A unit and jumpers to get the motor power and sound back to the B unit.
I have many loco sets with a single decoder. Mostly Stewart FTs that are permanently coupled together. I also run a power bus between them so the decoder gets power from all 16 wheels.
Hello QRN,
What is it you are hoping to achieve by sharing one decoder across multiple motors?
I would recommend three separate decoders, each with their own address, for the following reasons:
1. You have the flexibility to run them together or separately;
2. Consisting will allow you to operate them together anyway;
3. Each motor can rely on its own pickups;
4. Separate decoders will allow you to "trim" the settings so that each runs at almost exactly the same speed. You're going to find that each motor runs at a different speed and requires a different minimum voltage to begin moving.
Hope this helps.
Cheers
The_Ghan
With the current prices of individual decoders for each locomotive, the hassle of having to add wires between them and the modifications that would have to be made to the non-decoder equipped engines is not worth it.
What brand of locomotives do you have? Some brands draw more current than others, and one decoder probably cannot handle three motors.
It will work as long as the current rating of the decoder is not exceeded. Three would most likely exceed the rated stall current, You would also need to make modifications to the circuit boards in each of the non-decodered engines. this assumes you installed a replacement circuit board decoder in the center engine. Motors would need to be isolated from the frames by cutting the proper traces on the circuit boards.. There is a capacitor on each board that needs to be removed. If control of the lights was desired, three more wires and additional modifications to the board would also have to be done.
I've made these modifications to a pair of Kato SD70' because I had wired decoders in a drawer to install. I just completed installing a couple of left over DZ123's in a pair of GEVO's. It can be done but patience, a file, and soldering is required. Total savings was about $10 but it cost me an hour to do one engine.
I know where you are on this. I was trying the same thing beck in the mid ninety's when the lowest cost decoders were about $50. To me, the extra work as well as the ugly look of the wires jumping between engines just didn't appeal to me.
Martin Myers