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Showing results for tags 'reversing loop'.
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Reliable DCC and reversing loop POC (keep-alive, dual frog juicer, pfx brick)
NilsvN posted a topic in LEGO Train TechHi all, I've got something cool to share with you. I've been planning how to tackle my next 9v layout where I want to control multiple trains on a interconnected set of loops. On a regular 9v layout, you cannot do that. This is my solution: It's a 9v motor with the motor taken out, feeding into a bridge rectifier (into the A/C connectors) so that the output polarity is always the same. Then from there it goes into a step-up converter set to 10v output (track power is ~12v, but a bit lower on the frog). From the step-up converter it's connected to both a TCS KA3 keep alive and a PFx Brick. The keep alive ensures that the PFx Brick stays powered (and keeps the motors running) if power suddenly cuts out very briefly. Let me explain why that is important: For the reversing loop I'm using a TCS dual frog juicer. Basically, the "loop" part of the reversing loop is an isolated section of track, which we'll call the frog. You connect track power to the dual frog juicer input and connect the output to the frog. When the train drives from normal track onto the frog and the polarity of the frog is "the wrong way round", then it will automatically switch the polarity of the frog. This happens very fast, but it's enough of a delay when going into the bridge rectifier and then into the PFx Brick that the PFx Brick shuts off and turns on again, effectively stopping the train. That's where the keep alive comes in! Demonstration: (watch the indicator LED change between red/green, this means polarity gets switched) https://bricksafe.com/files/SystemTrains/lego-dcc-train-concept/video 1.mp4 https://bricksafe.com/files/SystemTrains/lego-dcc-train-concept/video 2.mp4 In the demonstration I used a PF remote. For my layout I'm going to be using Vincent Vergonjeanne's fantastic piece of software to control the PFx Brick with a Powered Up remote using bluetooth. That way I can control every train even when they are going through a tunnel for example. Here is the full post about the software: [link] I hope you found this interesting :) Thanks to Lazarus992 for the tutorial on how to open up and remove the 9v motor
Small track loop?
Kumata posted a topic in LEGO Train TechI have limited room with which to build my layout and am trying to cram as many features into as small a space as possible. To this end I wondered if anyone knows of the most space-efficient way to create a reversing track loop. I found this in an old topic, but is this the smallest possible build?