Questions tagged [electronics]

Electronics are the branch of physics and technology concerned with the design of circuits using transistors and microchips, and with the behavior and movement of electrons in a semiconductor, conductor, vacuum, or gas.

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3 answers
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Recommendation on how to build a "brick presence detector"?

I want to build a model of a complex machine with Lego and Arduino or a Raspberry. The machine model also features several accessories that can be added or removed during operation of the machine ...
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0 votes
2 answers
109 views

What is the carbon footprint of running a Spike Prime robot? [closed]

We are trying to calculate how much carbon is emitted from running a Spike Prime robot off one charge (roughly 8-10 hours)?
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2 votes
0 answers
77 views

Fixing a LEGO M Motor connector

I have several broken "Powered Up" M motors and I took one apart to see what was wrong. I ended up snipping off a section of the wire and re-soldering it back together but testing with an ...
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1 vote
0 answers
130 views

Problems with the main rotor speed in Airbus H175 (42145) set?

I'm having problems with the main rotor in "slow" position. The speed stays the same no matter what position the joystick is in. On the other hand, in "fast" position the blades ...
2 votes
1 answer
141 views

Where can I get replacement battery connectors for old Lego Duplo Train?

I have the same Duplo Train that Pieterjan posted a picture and video of in September ('Old Lego duplo train not working on batteries'). In my case, it is clear that the battery connectors are ...
2 votes
0 answers
49 views

Is there any good comparison of Lego Electric systems? [duplicate]

Coming back to Lego after a 20 year break gave me headache when discovering the electric systems available. Is there a good comparison around or could we make one here? What connector fits, what ...
4 votes
1 answer
105 views

Transformer 45517: power supply or charger?

I would like to build a charging station for EV3 with rechargeable battery (45501). Does the transformer (45517) give a simple stable dc voltage (power supply)? Or does it provide a controlled voltage ...
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6 votes
1 answer
788 views

What electronics are inside the SPIKE Prime angular motors?

Is there any information available about the internals of the SPIKE Prime and Robot Inventor angular motors? What Hall-Sensor is used by the SPIKE motors? To be more precise: I'd like to get ...
3 votes
2 answers
700 views

What is inside the LEGO Powered Up L motor?

What's inside the Powered Up L motor (part bb0959c01)? How do its internals compare to the XL motor and the M motor?
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5 votes
1 answer
271 views

EV3 not recognizing resistance correctly (MicroPython)

I recently tried measuring the resistance of a thermistor using the .resistance() method, the results are sadly not accurate. I measured the resistance with a multimeter and it showed 100kΩ, while the ...
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5 votes
1 answer
686 views

Continuous power supply for the SPIKE Prime or Robot Inventor hubs?

The hubs present in the Mindstorms Robot Inventor or SPIKE Prime sets have 2100mAh lithium-ion batteries which can be charged with the accompanied cable with a micro USB connector on one end and a ...
3 votes
1 answer
143 views

Can an EV3 power a buggy motor with the NXT to 9V extension cable?

On Philo's motor comparison webpage, https://www.philohome.com/motors/motorcomp.htm, it says that the buggy motor (42908 lego id, 5292 bricklink id) is not recommended to be powered by an RCX as the ...
6 votes
1 answer
618 views

Train with two Powered Up hubs

I'm building a motorized train. The locomotive has two Powered Up train motors, one at each end. However, no matter where I place the hub inside the locomotive, the wires on the train motors are too ...
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0 votes
0 answers
217 views

How to increase the voltage supplying to technic motor through the Technic hub?

I have four Technic Large Motors, all connected to a technic hub. I am using the motor to turn some large propellers and the hub is powered by six 1.5 V (maybe less) batteries depending on the brand. ...
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7 votes
1 answer
177 views

What is the max current for the EV3 I/O port's VCC pin (pin 4)?

The LEGO EV3 Hardware developer kit says that the fourth pin of input or output port provides a voltage of 5 volts but doesn't give the the maximum current that can be drawn from the pin. What is the ...
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5 votes
2 answers
220 views

How does the 8365 Tuneable Racer work?

The set 8365 Tuneable Racer has tunability as its main feature, meaning the motor's parameters can be changed by adding, removing or swapping certain additional elements. However, these parts seem to ...
  • 14.7k
4 votes
0 answers
47 views

How do I sync audio and movement on my NXT 2.0?

How do I sync audio and movement with my NXT 2.0? I'm building an animatronic head and I can't find a good way to sync it with external audio because the internal speaker is too quiet.
4 votes
1 answer
251 views

Does LEGO sell a DC relay for Power Functions?

I’d like to use a signal from a (5V) littleBits circuit to control some (9V) Power Functions motors. Does LEGO sell or recommend a DC relay to facilitate this sort of thing? If the answer is no, I’d ...
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8 votes
2 answers
1k views

How do the Infrared Towers work?

I've seen a few Mindstorms "infrared transmission towers" listed on Brick Owl, Bricklink and other sites. However, I cannot find any good documentation that how they work, how they are used ...
  • 450
3 votes
1 answer
108 views

What is the maximum voltage for motors from Cybermaster units?

I recently bought a non-functioning Cybermaster unit [part:71797]. As the motors in there might be perfectly fine, I'd like to use them. I could not find information on these motors (as opposed to ...
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5 votes
1 answer
1k views

What internal electronics does the Control+ Technic Hub (88012) use?

I'm interested in comparing to the other Powered Up hubs, which are already documented here: Mindstorms v4 / spike prime What internal electronics do SPIKE Prime and Mindstorms v4 use? train 6AAA hub ...
4 votes
1 answer
1k views

Does the Mario Starter Course require a smart device?

I've seen that the Mario Starter Course (71360) requires a smart device to play: I'm trying to limit the amount of screen time that my child consumes, and I'm wondering exactly how required the smart ...
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8 votes
2 answers
722 views

How to integrate hardware/embedded button with LEGO?

I have two different buttons (B3F-1000 and 3a250vac switch) which I want to integrate into a LEGO "machine" which I'm powering with an Arduino. Since the rest is integrated into LEGO plates, ...
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11 votes
1 answer
3k views

What internal electronics do Spike Prime and Mindstorms Robot Inventor use?

What electronics live inside the SPIKE Prime hub? How powerful is the hardware?
  • 37.4k
7 votes
1 answer
947 views

What is inside the Technic Powered Up XL motor?

What components are inside the new Technic Powered Up XL motor? Is it the same as the PF XL motor, except with a different connector?
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5 votes
1 answer
989 views

What is inside BuWizz 2.0?

I'm interested in Buwizz PCB and components. Can someone share good photos of the Buwizz PCB (both sides)? It will be very cool to see Buwizz 2.0 but older versions will also be good.
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3 votes
1 answer
97 views

Use D output in 42099 (4X4 X-treme Off-Roader) set

How I can use the D output for an additional motor in the 42099 set? Or how can I use a custom control skin?
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1 vote
2 answers
169 views

Scarcity of electric parts: motors etc

Having bought parts in bulk several times I came to realization that electric parts are scarce resource in Lego world. The cost of plastic parts comes at around 10% of original price but there are so ...
2 votes
1 answer
340 views

Problem-shooting on 8070 "Super Car" with Power Functions

I have recently bought a used Lego Technic car (8070 Supercar). It was not fully built, and from the instructions I learned that it was fully built except for approximately the last 10 steps. I ...
0 votes
1 answer
1k views

Arduino-izing LEGO Technic - and now I need some ideas for the Lego Service Truck 8071

I am starting a project - Arduino-izing LEGO Technic - and now I need some ideas for a car / vehicle to choose. This project starts out as a quest to find a way to combine the ease of LEGO Technic ...
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1 vote
1 answer
78 views

Can a v1 PF reciever power an XL motor and servo?

I have a v1 PF receiver but don't want to pay $35 for a v2 receiver and I was wondering if a v1 receiver can power a single XL/L motor and a servo.
4 votes
2 answers
208 views

Custom extension cables for Light Stax?

Recently, I got the S-12012 Light Stax kit with 50 (!) light bricks. They are different from those described in this question, but they are much cheaper, colorful and with blinking/pulsating effects. ...
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1 vote
1 answer
145 views

My DUPLO railroad engine stops after 20cm

My DUPLO railroad engine stops after 20cm moving. I suppose the sensor in the front axle is damaged. So is it possible to repair it?
5 votes
2 answers
2k views

What is a good third party battery box and receiver?

I got the LEGO 4x4 crawler for my birthday and I love it. But there is one slight thing which I hate: it has terrible range when using it outside. I know there is BuWizz which is a third party ...
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6 votes
2 answers
972 views

Arduino-izing LEGO Technic - ideas for a car / vehicle to choose

I am starting a project - Arduino-izing LEGO Technic - and now I need some ideas for a car / vehicle to choose. This project starts out as a quest to find a way to combine the ease of LEGO Technic ...
  • 173
10 votes
4 answers
7k views

Which programming environments or APIs are available for the LEGO BOOST?

Over the holidays I tried the following Python library: https://github.com/undera/pylgbst but I couldn't get it to work. Then again my knowledge of Python is very limited. I'm more experienced with C+...
12 votes
1 answer
2k views

Replace Battery in LEGO Dino Attack Light-Up T-Rex Head?

Is it possible to replace the battery of the LEGO Dino Attack T-Rex head? There's a button on the top of the head that makes the eyes and tongue light up red, presumably via a red LED. There doesn't ...
5 votes
1 answer
559 views

Are there any difference between the Power Functions 88003 and 99499 L motors?

I am planning to attempt a couple of RC MOCs and was looking up the power functions L motor on BL and found that there are actually 2 types of the L motor, namely the "88003 Power Functions L Motor" ...
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9 votes
2 answers
585 views

Duplo Locomotive: What is this inner part used for?

Background I was forced to completely disassemble a duplo locomotive. My son played with it in a sand box and, guess what, it was not working anymore. I used a small brush to clean every single part (...
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9 votes
1 answer
2k views

What is inside the LEGO Powered Up M motor?

What is inside the M motor in the new Powered Up system? How is it different from the older Power Functions motor?
  • 37.4k
6 votes
2 answers
774 views

Stacking motors on the Powered Up hub or Boost hub

The way the Boost/Powered Up connectors are designed, it's not possible to have multiple motors on the same output of a hub like it was possible with 9V or Power functions. However, since I only want ...
1 vote
1 answer
328 views

Are there active electronics in basic Powered Up motors?

Powered Up is a more advanced system than the Power Functions system that it is replacing. Does each component contain active electronics that identify it to the hub that it is connected to?
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11 votes
1 answer
2k views

What electronics are inside the LEGO Powered Up hub?

I'm curious what the internals of the new Powered Up hub look like? What components are inside?
  • 37.4k
6 votes
2 answers
4k views

Repairing disintegrated old 9V wire

I have a number of old technic motors and battery boxes I would like to use however the wires have disintegrated in storage to the point that the metal conductors touch and short out. Does anybody ...
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4 votes
1 answer
148 views

The route a power line takes through a neighborhood

I have a small Lego town built. I want to add power lines. However, I don't know how to route the power lines through the neighborhood. Should I create one line that snakes between all the houses? ...
  • 263
2 votes
3 answers
726 views

Bucket Wheel Excavator not powering up?

I just finished to assemble the Bucket Wheel Excavator (42055) set, I inserted new batteries in the battery box and tried to power it up. The LED on the battery box blinks for a millisecond almost ...
8 votes
1 answer
459 views

Classic 9V battery box current limiter?

Recently I disassembled a classic 4760c01 Electric 9V Battery Box Small Complete Assembly to see what was inside. Battery Box: Disassembled: In the switch component, we find what appears to be a ...
10 votes
1 answer
4k views

Why are there 4 wires leading to the Power Functions LEGO train motor?

Does anyone know what the wires do? If the Power Functions train motors are simple DC only 2 wires would be needed or is it more complex than that?
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5 votes
1 answer
117 views

Is there a way to buy just the robotic parts?

I apologize if this is a silly question. My kids recently went to a LEGO robotics workshop at our local science museum and LOVED it. Is there a way to buy just the robotic parts (motor, sensors, ...
6 votes
2 answers
740 views

How to fix the 4.3V output supply of a NXT 2.0?

I have a Mindstorm NXT 2.0 from 2007 (PCB code: 62115.40H) at which the sensors except the simple "Touch sensor" are no longer working. Also the tacho-signal of the motors do no longer work. (The ...
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