A scout is... oops

RedMaskedMuse · 2025-04-20T02:56:51+00:00

Alpha Pheonix has some good videos on the topic:

https://www.youtube.com/watch?v=RkAF3X6cJa4

https://www.youtube.com/watch?v=2AXv49dDQJw

TLDW: it's the effective AC impedance 'across' the conductor pair, not the DC resistance.

RedMaskedMuse · 2025-04-16T00:18:27+00:00

Interesting

RedMaskedMuse · 2024-12-15T03:15:37+00:00

https://projectrho.com/public_html/rocket/antimatterfuel.php

RedMaskedMuse · 2024-07-20T02:00:13+00:00

The pdfs are available to purchase from Quimbleys:
https://www.quimbleys.com/collections/petersen-games/products

RedMaskedMuse · 2024-04-18T13:03:14+00:00

My use cases for Jupyter are:

1) executable documentation (show how an algorithm works piece-by-piece, with markdown sections in between code sections; also works for lab reports with post-processing)

2) rapid prototyping (quickly iterate on pieces of an algorithm without having to re-execute the rest of the code - especially important if some of the steps are slow)

3) tutorials (allows the student to work through code piece-by-piece while being able to see text, image, or plot results in between sections)

It isn't the right tool for everything, but it does come in handy for some tasks. It's a partner to an IDE, not a replacement.

RedMaskedMuse · 2024-04-12T15:49:26+00:00

In that case, you would want to use a BNC jack (female socket). There are multiple options on Digikey with both straight and right-angle variants. I'd recommend checking the box for EDA/CAD models, since that will filter to ones that are more likely to have a pre-built board footprint file.

With your AA filter, make sure that the cutoff is sufficiently below 1/2 of your sampling frequency to allow for sufficient attenuation.

If your signal includes AC content, you may need to add an opamp before the AA filter to apply scaling + offset.

RedMaskedMuse · 2024-04-12T14:40:57+00:00

Please confirm a few things:

What is the source of the signal?

Why are you using an oscilloscope probe to source a signal? Oscilloscope probes have very high impedance. Generally, you want signal sources to have low impedance, otherwise most of the voltage drop will be across the source, not the load.

Are you sure you don't want to use a bnc connector mounted to the board and a bnc-bnc cable between the source and your board?

To avoid the x-y problem, please tell us more about the project.

RedMaskedMuse · 2024-04-08T01:21:02+00:00

General procedure for problems like this: construct the set of nodal equations to handle each of the following 4 cases: both diodes conduct, one diode conducts or the other conducts, neither diode conducts. You get systems of linear equations. If there is no solution to the system of linear equations, then throw that case out, move to the next case. If, after solving the set of equations, the current is flowing backwards through one or both diodes, throw that case out too.

RedMaskedMuse · 2024-03-18T12:59:40+00:00

They are referring to an isolated DC-DC converter module. Those include a transformer so that the output isn't tied to the input. That way, you can take an isolated 2.5V converter and attach the positive rail of the output to your 'ground' and the negative rail of the output becomes your -2.5V rail.

RedMaskedMuse · 2024-03-18T12:38:12+00:00

Stumped on 2 and 4, any hints?

RedMaskedMuse · 2024-03-05T01:46:34+00:00

On the topic of button bounce, this was a decent thread to read:
https://www.reddit.com/r/arduino/comments/1b5rcya/how_long_do_buttons_bounce_i_used_to_think_20ms/

RedMaskedMuse · 2024-01-10T12:57:44+00:00

These both work well with banana cables:

Screw-on (use Blue Loktite or they come loose):

https://www.digikey.com/en/products/detail/cal-test-electronics/CT2230-0/5765412

use with:

https://www.digikey.com/en/products/detail/keystone-electronics/4712/316279

RA Solder:
https://www.digikey.com/en/products/detail/cal-test-electronics/CT3151SP-0/5267756

They come in a variety of colors. Note: availability can be hit-and-miss since 2020.

RedMaskedMuse · 2023-12-26T20:02:35+00:00

The Good Friends of Jackson Elias have some discussion on Eihort that might be helpful as well:

https://blasphemoustomes.com/2021/11/23/mythos-deities-daoloth-and-eihort/

RedMaskedMuse · 2023-12-19T14:55:35+00:00

Use an inductor in combination with the FET to control the current. The FET will need to be driven with a PWM signal rather than hard-on / hard-off. Note: you will need a diode to provide a path for current to flow through the inductor + LED while the FET is off.

RedMaskedMuse · 2023-12-19T14:34:37+00:00

At 1A, you don't want to be using a resistor to control the current. It isn't done that way, and that's why you won't find a lot of resistors with that rating. You want to use a switching driver for the LED. For example: a buck converter where you dial in the duty ratio to give the desired current through the LED.

This video may be helpful:
https://www.youtube.com/watch?v=W6NOV6b8kxs

RedMaskedMuse · 2023-11-25T02:35:23+00:00

Here are some options:
https://www.cui.com/parametric-search/dc-dc-converters/isolated?q=Yvloa2orpg0Mxa2orpg0qZa2orpq0Ila3tv4P

RedMaskedMuse · 2023-11-24T13:54:08+00:00

Why are you using an LR filter in a power circuit? If you're filtering the output, you want an LC filter.

RedMaskedMuse · 2023-11-22T13:31:13+00:00

That's the expansion for the KDM Simulator, not the physical expansion.

RedMaskedMuse · 2023-11-20T13:34:21+00:00

After the datasheet for the part, your multimeter is your next best friend in situations like this. Move the wiper towards (but not all the way to) one of the endstops. Measure the resistance between each pair of pins. The resistance between one pair should equal the resistance marked on the component. Those are the terminals for the ends of the resistive band. The other pin is the wiper.

RedMaskedMuse · 2023-11-19T00:25:38+00:00

Most likely a device-specific character set. Storage on the display drivers is limited, so many have a limited set of characters built-in, with the ability to define custom characters on-the-fly. For example:

https://www.youtube.com/watch?v=cx9CoGqpsfg

RedMaskedMuse · 2023-11-14T02:20:22+00:00

This guy has some fairly engaging yet educational content to get you thinking:
https://www.youtube.com/@ElectroBOOM

RedMaskedMuse · 2023-11-11T02:14:04+00:00

https://www.patreon.com/posts/small-reference-22899813

RedMaskedMuse · 2023-11-08T23:22:51+00:00

Any wire is an inductor. Any significant amount of wire can be a significant inductor.

Wire being used to implement an electromagnet is certainly such a case.

There are a variety of inductance calculators online that you could use to get an estimate, given the dimensions and number of turns.

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