Questions tagged [construction]

13 questions
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How do I improve a simple home-made capacitor?

I was explaining to my son that a capacitor is simply 2 sheets of foil separated by a dielectric and rolled up and he said, "can we make one then?" I'm giving it a go. I used household aluminum foil and some parchment paper. I cut the foil into two…
nuggethead
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Better ways to make a 300 milliOhm potentiometer than using 2 feet of #30 wire and a copper clip

Goal I'd like to design a potentiometer, with a range from \$0\:\Omega\$ to about \$0.3\:\Omega\$ , for calibrating the zero-reading of a COTS digital voltmeter. I'd like it to be easily fabricated by any hobbyist and easy to use in practice, while…
periblepsis
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Soviet-era mounting techniques to absorb vibration (THT components)

This question is about a historical point of view. I was watching this video about a Soviet-era dialer. As many Russian devices of that time, the construction is simple and in some aspects strange (designed with simple tricks to lower the cost). At…
gino
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How could they correctly wire massively complex point to point devices?

This is an example of point to point wiring:- Wires everywhere and mostly grey or orange, with a few coloured ones thrown in. The equivalent circuit schematic must be huge. So I have three related questions:- How could this be wired correctly in the…
Paul Uszak
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Mechanical construction of PCB. What is between the layers?

I came across an answer about the construction of a multilayer board. It included an image showing the mechanical construction of a board (see image 1.) This prompted me to think of the actual construction a bit more. Image 1 : Construction of…
joojaa
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Variance in winding a toroid

I'm building a filter from a kit with some given (microscopic pre-soldered SMT) capacitors and 2 toroids. It looks like the notch frequency is a bit too low with 10 wire turns around a T37-2 iron powder toroid and a bit too high with 9 turns. The…
hotpaw2
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Where to find winding diagram for a 56 pole 63 slot BLDC motor?

I'm working on an algorithm to control a BLDC motor with 56 poles and 63 slots. I'm using trapezoidal control. By employing usual switching sequence (CA - CB - AB - AC - BC BA) I'm missing one step in the six step commutation. Where am I going…
Vivek Vijayan
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Question about Disconnect Switches

I'm looking at an electrical construction drawing and I just keep forgetting what the disconnect switch notations mean. Refer to the attached image. This is what I'm assuming: the number in the first quadrant of the circle is the number of poles, 3,…
syed.karooney
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Effect of EMI/ESD on excavator electronics?

I'm building a teleoperation retrofit for excavators. Setup is a control box mounted behind the operator seat, powered off the 24V battery/alternator bus, with actuators near the OEM joystick/pilot controls. I'm trying to identify the most…
MaD Boston
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Are variable capacitors compatible with breadboards still available?

Variable capacitors are used less, since the preference is for digital adjustment. And through hole parts are used for less, since the preference is for SMD. Finally, many variable capacitors have leads too large to fit into breadboards.…
SRobertJames
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Parts of a power cable

This is a snippet of 6kV/Single core/240 sqmm copper cable. The parts of the cable are as follows. Stranded Copper Semiconducting Cross-linked compound XLPE Semiconducting Cross-linked compound Semiconducting Tape Copper Wire Copper Binding Tape…
Nikhil Kashyap
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Crystal oscillator construction

I am not sure about how the crystal oscillators are made. Some say it has a crystal but some says it has an LC combination which requires a parallel capacitor to resonate with the internal LC combination.What is the actual construction.
kam1212
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Experimental low-pass filter construction using a NanoVNA?

Suppose I wanted to construct a no-solder plug-board or rats-nest low-pass filter for VHF frequencies, but without the "proper" circuit substrates, design software, or test equipment. Could an inexpensive NanoVNA be used to test and incrementally…
hotpaw2
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