Questions tagged [model-railroad]
The model-railroad tag has no summary.
15 questions
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What type of optical sensor can measure the displacement similar to an optical mouse?
Imagine there is a simple 2-wheel bogie on a rail:
Bogey has:
Rubber wheels with the same profile as the rail for a "perfect" grip
Low rail clearance. Bottom of the battery (yellow) is ...
- 144
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368
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Using MOSFET to Control 2 LEDs Separately from Same 12V Source
I am trying to control 2 LEDs from a model railway decoder. The decoder has a common positive terminal (+12 V).
The decoder also has a two negative terminals - one I have called FL and the other I ...
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How can I reverse the polarity of a DC model train (12 V) using MOSFETs instead of relays?
At this moment I reverse the polarity of the traction voltage of my 12 V analog model railroad (older Fleischmann models) by using relays, driven by an Arduino microcontroller. However, I want to ...
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Short circuit protection for an analog model train controller
I am developing a circuit for somebody else to control 3 analog DC model trains. I am unsure how I should make the short circuit part. There are more ways to achieve this.
My idea is as follows:
1 ...
- 646
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DC automatic polarity inverter
I'm putting a Raspberry pi zero on a model train. The train tracks supply 12V DC which I step down to 5v with a Pi Jack. However, because the power is being supplied via the tracks, I can't be certain ...
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Zener diode question in simple LED circuit with anti-flicker for model railroad
I am a total novice when it comes to electronics. I had a simple circuits class 30 years ago as a software undergrad. I've designed a simple LED lighting circuit for N-scale model railroad, to be ...
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Need help determining smoothing capacitor(s) for rectifier
I am making a rectifier for a single N-Scale train building. It takes DC, but the train controller gives out 19VAC. I have 4 1N4001s and some capacitors, but probably not the right size/uf. I only ...
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LED color changing circuit using power cycle
I'm trying to design an LED circuit for a model that will allow me to change the color of a bi-color LED each time the power is cycled. In other words:
Power off: Nothing
Power on: Green
Power off: ...
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Drawn out question in regards to DC power to battery backup
Story:
I have a lego train that is modded to run off of a 9v train track rail system that was a control function of 0 to 9 volts when fully on. LEGO does not make the motors that can run on these ...
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Motor Control System for LGB Trains
I am currently experimenting with some motor control circuitry for my garden train. I have spent several time trying to read up on the basics of motor control, and I have also done some prototyping. I ...
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Converting 12VDC to 1.5VDC
How do I convert 12vdc to 1.5vdc for flashing mini-lights on my HO Scale Railroad system?
The flasher will drive 2 alternately flashing bulbs (1.5 volts each)
The maximum output of flasher is 100mA @ ...
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How to re-magnetize a permenent magnet motor of small size (model railroad)?
I have several small DC motors where if I place an extra magnet to back-up the included magnet, the performance seems to improve significantly.
These motors are 30-40 years old & their ...
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What is a good approach to detecting distance and speed in model railroads?
Up front I must admit to little hands-on knowledge of modern microcontrollers and their software - I know power engineering and big motors much better (45 years of it).
Now, my question:
Trying to ...
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Adding capacitor to model railway 12V motor to keep it going over a dead spot
I have read that you can add a capacitor to a model loco to keep it going over a dead spot on the track - not DCC - just DC. Is this accurate? On one forum someone has been experimenting with 2000mF ...
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Can I control a model train with a lighting dimmer pack?
I have an O-scale 3-rail track model train. I would like to be able to control this with a computer.
The normal model train transformer/controller goes from 0VAC at "stop" to 18VAC at "full speed".
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