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| rs20:
--- Quote from: danners430 on November 06, 2018, 11:01:15 pm ---That seems like a sensible idea - I suppose to get around the bipolar nature of the signal, I could run both feed wires to the track through the transformer? --- End quote --- Kirchoff's current law dictates that all the currents in a loop are equal, so there's no difference in the currents in the two feed wires, and so no point in running both wires through the transformer. Unless I've misunderstood and the system isn't a simple loop. |
| danners430:
--- Quote from: rs20 on November 06, 2018, 11:32:14 pm --- --- Quote from: danners430 on November 06, 2018, 11:01:15 pm ---That seems like a sensible idea - I suppose to get around the bipolar nature of the signal, I could run both feed wires to the track through the transformer? --- End quote --- Kirchoff's current law dictates that all the currents in a loop are equal, so there's no difference in the currents in the two feed wires, and so no point in running both wires through the transformer. Unless I've misunderstood and the system isn't a simple loop. --- End quote --- Aye, that's a fair point... Not sure what you mean by loop - basically the two rails on the model railway act as the positive and negative (if it were DC) feeds to the trains. With DCC, they are alternately powered, first a pulse on one rail then on the other rail. Speaking to another friend off the thread, he suggested keeping everything up to U1B to "rectify" the voltage for ease of programming... Sent from my ONEPLUS A3003 using Tapatalk |
| rs20:
--- Quote from: danners430 on November 06, 2018, 11:35:55 pm ---Not sure what you mean by loop - basically the two rails on the model railway act as the positive and negative (if it were DC) feeds to the trains. With DCC, they are alternately powered, first a pulse on one rail then on the other rail. --- End quote --- I mean there's a wire, then a train, then another wires. Kirchoff's current law says that if there's no other paths for current to flow, then the currents are equal through all three of those components and there's no point feeding both wires through the CT. --- Quote from: danners430 on November 06, 2018, 11:35:55 pm ---Speaking to another friend off the thread, he suggested keeping everything up to U1B to "rectify" the voltage for ease of programming... --- End quote --- That makes absolutely no sense. We're only testing for presence; the negative swings are unnecessary and are discarded by D1. If you're going to add a dozen extra components to your design, you should probably have a clear reason why? |
| danners430:
To be honest, he completely lost me with his explanation... J reckon I'm going to quite simply go out and buy some components and do some testing :-) Sent from my ONEPLUS A3003 using Tapatalk |
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