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A Photon's Perspective on Life

EM photons travel at the speed of light, c, from the moment of their creation, to the moment of their extinction. From the perspective of a photon, time does not pass. You could even say that to a...

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Prośba o wyjaśnienie schematu

W datasheet acs712 stronie 12 są przykłady aplikacji, chodzi mi o aplikację numer 4 czyli z interfejsowanie się z układem 3,3v.. jest dzielnik rezystorowy a później dioda. Po co ta dioda skoro...

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la Suede et la superiorite technologique !

slt, pour faire la recharge au feux de camp voila : que ici, c'est pas evident ! Sep 30, 2022 Sep 30, 2022 Le samedi 1 octobre 2022 à 21:29:08 UTC+2, ptilou a écrit : peut on faire une pile...

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newlib and time()

I often use newlib standard C libraries with gcc toolchain for Cortex-M platforms. It sometimes happens I need to manage calendar time: seconds from 1970 or broken down time. And it sometimes happens...

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Meyer Sound 833 problem

I have a Meyer Sound 833 control unit on my bench. It has a weird fault that appears to centre around a 15kHz oscillation that affects one channel, directly, but is bleeding through to the other...

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Wattmetro uscita 0-20mA o 0-10V

Buon giorno, avete mai visto wattmetri con uscita analogica 0-20mA o 0-10V? Grazie Buona giornata U.C. Il giorno Tue, 13 Sep 2022 12:13:30 +0200 umberto ha scritto: A lancetta no, a display si'...

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Hear sounds from TV to my radio

I want to hear sound from my Tv using my standalone radio. All the TV output HDMIs are being used. My inputs on my radio for TV/Dbs are coaxial. What parts do I need? Thanks. . Look up "F connector"

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Vjetroelektrana + Solarni panel

Imam vjetroelektranu na 24V i Solarni panel na 12V. Kupio bi 2 akumulatora po 12V ( 100Ah + 40Ah) i spojio u seriju da dobijem 24V. ulator od 100Ah bi spojio solarni panel 12V. Na akumulatore bi...

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Ed McGaw

This is a long shot, but I've been asked by an American friend if I can locate a guy called Ed McGaw. He worked for Scientific Atlanta and/or Quan-Tech in New Jersey some years ago. He resides in...

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Wide frequency range, arbitrary waveform DDS

To generate frequencies from approximately 0.5 mHz to 12 MHz with a DDS a minimum clock of >24, say 25 MHz, is required. To be able to go down to 0.5 mHz, a phase accumulator of at least 36 bits is...

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Frequently Asked Questions All FAQs »

wart overvoltage protection

We make a gadget that's powered by a 12 volt wart, and sometimes a user applies 24 and blows one up. We have a polyfuse and a 12 volt TVS and they sometimes fry the TVS. It's posssible that most any...

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Raspberry Pi Sound card problem electret condenser microphones

I want to process the signals of five electret condenser microphones with raspberry pi and i since the RPI has no audio inputs im thinking of using a sound card. Im looking for a sound card with five...

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Radio Reception - Massive Electrical Interference

Hi! I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived. Only problem with this place is that the main electrical drop to the building is...

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Rectangular LEDS

I'm thinking of making a Set Theory Clock display for a desk clock and using LEDs for its display. This needs a selection of rectangular red and yellow LEDs, both small stackable ones that could be...

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Driving LEDs with constant voltage

I have some 7-segment displays I'd like to drive from a uP output...the segments have a common cathode. 5 volt digital outputs from the uP are available, and the red LED segments have a forward...

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Controlling alot of LEDs from Arduino or AVR. Maybe 74HC595

I am trying to create a project much like like a Marquee sign, I want to be able to control hundreds of LEDs from a set of chips. From my research I found the 74HC595 chip and using a bunch of these...

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Solved Issues All Solved »

Soldering gun tip - Weller DIY tipreplacement

I have a Weller soldering gun & the tip burned through. Not having a spare, I took a piece of 12ga copper wire and improvised (I know, it won't last long). I find it so fiddly to get the ends bent...

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~ OT? Dust in a computer

Any good solutions to keep the dust out? Anyone doing anything along those lines - and how's it working? I have a desktop that's less than a year old and is packed with dust already. I can't make the...

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Repair of Samsung 55" TV - backlight problem

Friends of mine have a Samsung 55" 4K TV, model UN55HU6840 (about 2014). They say they can hear audio, but the screen is black. I'd like to take a shot at fixing it for them since they don't really...

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Categories

Featured more »

sluggish remote control | Have any of you noticed that your remote control, for a tv or whatever, doesn't work at first, if you haven't used it for a day or two? In particular, some comp...

sluggish remote control

Have any of you noticed that your remote control, for a tv or whatever, doesn't...

Meyer Sound 833 problem | Meyer Sound refuses to supply a schematic. When I informed a company (can't recall which one) that they had to supply me a schematic by state law, they essentia...

Meyer Sound 833 problem

I have a Meyer Sound 833 control unit on my bench. It has a weird fault that...

Scumacher 1042A-PE battery charger has no output. | Thanks for your reply. Thanks for your reply. Since there's a 38 ohm (internal resistor?) connection between the cathode and gate, does that mean the 1.5 V puls...

Scumacher 1042A-PE battery charger has no output.

This Schumacher 1042A-PE battery charger stopped functioning today. It seemed to...

I direct wired Plug and Play LEDs, is this bad? | LED tubes internally are wired to the supply at one end, the other end is made as a short circuit - so that the LED tube can be used as a plug and play for a fl...

I direct wired Plug and Play LEDs, is this bad?

I replaced the ballast and fluorescent tubes in a bathroom fixture with LED...

Dot matrix display | could be common anode or common cathode Hi, Roger. I can see that there are 8 anode pins and 6 cathode pins but that is about as far as I get. If you apply 7 bi...

Dot matrix display

I have been given a number of 7x5 dot matrix display segments. There are 7 pins...

Soldering a LED Display Matrix | I was trying to build a 5x5 LED matrix (because I only have 25 LEDs right now, and it seemed like a good start). I was soldering all of the anodes together for ...

Soldering a LED Display Matrix

So, I've learned the hard way that it isn't trivial to solder a LED matrix. I've...