Burglar Alarm | Project 11/20 | Maxitronix 20in1 | Learning Electronics In The Lab With Jay Jay

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In this video I do the 11th project from the Maxitronix 20in1 (the Sensor Robot 20): Burglar Alarm.

This project uses the reed switch to trigger a bistable multivibrator that controls an alarm. The bistable multivibrator can be reset with the key. An astable multivibrator is used to generate the tone for the audible alarm.

In this project we get some more experience with transistors and how they can be used in various types of multivibrator circuit. Under the thermal camera we can see some of the transistors warming up as they conduct electricity. With the oscilloscope we can see the periodic waveform used to generate the alarm tone.

Note: while I was making this video I needed to make some banana plug to hook clip cables (so that I could test the reed switch). I made a video of my making those cables which you can see here: Electronics Project #9: Making Banana Plug to Hook Clip Cables | In The Lab With Jay Jay.



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Yum Cha KT-908 Digital ThermometerThis is an image of the product.

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Most Important Skills for Electrical Engineering

Today I watched Most Important Skills for Electrical Engineering.

Stuff I need to learn includes:

He listed some important soft skills which included:

  • Critical thinking
  • Problem solving
  • Communication
  • Opportunity detection
  • Tenacity/high-pain-tolerance

Quake ported to Arduino Nano Matter and Sparkfun Thing Plus Matter Boards

Today I found Quake ported to Arduino Nano Matter and Sparkfun Thing Plus Matter Boards via this article from Hackaday: Quake In 276 KB Of RAM.

The code is on GitHub and there’s a YouTube video with a high-level explanation.

Demo #2: Resistor Box Banana Plug Modding and Demo | Learning Electronics In The Lab With Jay Jay

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In this video I mod a pair of resistor boxes by installing banana plug terminals in place of the lug terminals they came with and then I give a quick demo of them.

In the demo we connect them in both series and parallel and then measure their resistance with my Fluke multimeter.

I mention this video from Dave Jones on the EEVblog: EEVblog #1020 – Is A $7 LCR / Component Tester Any Good? which is where I found out about the RS-201W resistor box which he has. I searched on eBay for RS-201W but what I found for over US$1,000 (inc shipping) was way too expensive: IET Labs RS-201W Wide Range Precision Resistance Substituter.

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Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

Yum Cha 11 in 1 USB-C Hub USB HubThis is an image of the product.

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Mail Call #10: Thanks Craig! Also loot from AliExpress | In The Lab With Jay Jay

This post is part of my video blog and you can find more information about this video over here.

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In this video I receive Engineer’s Mini Notebook Volume II – Science and Communication Circuits & Projects all the way from the USA from my friend (and mentor (and reader (and viewer (and patron (and Lisp hacker))))) Craig. Thanks Craig! <3

I mention that the October 2024 edition of Silicon Chip magazine is out.

I mention that I recently got my symbol keyboard working on Linux! Pretty happy about that! These are the extra keys that I have at my workstation now: ° ± § λ Δ Σ Π Ω ε µ π θ

I also get a bunch of stuff from AliExpress, including:

And yes, despite confusion, I did get three lots of two different kinds of hard brushes, and yes, I did end up saying the wrong thing in the video! Can’t take me anywhere.

Oh, and as I mention in the video I am from a beautiful part of the world known as the Blue Mountains. It’s pretty hot here today!

In the end my collection of Arduino boards includes:

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Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

Wozniak Solder LugsThis is an image of the product.notes

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Old Book Teardown #10: Digital Systems: Hardware Organization and Design (1973) | In The Lab

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Silly Job Title: Component Wrangler

In this video I take a look at Digital Systems: Hardware Organization and Design by Fredrick J. Hill and Gerald R. Peterson published in 1973:

Here is the laundry list of links to things which came up during this video, including a few duplicates:

Thanks very much for watching! And please remember to hit like and subscribe! :)


Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

Rigol PLA2216 Compatible Logic ProbeThis is an image of the product.notes

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