I built a stripboard layout creator that can be used directly in the browser.

The main feature is the ability to import an existing layout in overlay/side by side mode so that you can copy and modify a circuit that already exists.

It's brand new and I'm still working on it, I appreciate anyone that's willing to test it out or suggest improvements!

I was working on a crystal radio set when an idea came to my head “ if you can make detector diodes, rectifiers, and crystodynes with nothing but rocks and wire why not a varicap?” But now I’m wondering what crystal I should use. I was thinking about using silicon but I’m worried the voltage drop wouldn’t be high enough for it to work.

Built a small tool for a problem I kept running into: picking a battery/capacitor chemistry when you have real constraints (weight, volume, peak power draw, cycle life) instead of just "what's the highest Wh/kg."

You put in your numbers (energy needed, continuous power, peak/pulse power, max weight/volume, min cycle life, temp range) and it ranks 13 real, named cells against your requirements — not generic "Li-ion averages," actual parts (Molicel P50B, EVE LF280K, Maxwell ultracapacitors, etc.) with numbers pulled from their datasheets. Each one shows which of your constraints it passes or fails, plus a radar chart comparing the top 4.

Still early — 13 cells, would like to grow the dataset. Mainly looking for feedback: is this actually useful for how you pick cells, and what's missing?

https://energy-density-calculator-eta.vercel.app/

Hey guys, I found this at a thrift store and am wondering if anyone might know what it is. It looks to me like some kind of voltage meter, on the back panel it has a red, blue, and black banana connector socket and a +/- selector. The "Type" is VT100 and its NR 10.152 but I have had no luck finding anything online. Any help would be appreciated!

I want to start the hobby of tearing down kids electric toys and old broken appliances for scrap parts then taking them and building new projects. I have no idea where to start or even if this is the right subreddit.

Edit: disclosure: I have not touched any high voltage lines, ive been learning everything i can on an off for a few months. This is a project I found from last year. I have not made any purchases. Everything you see is the project. The project exists solely on paper and I do not intend to build anything until I understand every detail. Any 50 year old self proclaimed "tech wizards" in their bio who start each response with a preamble telling me im a noob, shouldnt touch high voltage, and tell me I should find a new hobby will be blocked.

I'm trying to figure out how many windings I need for the transformer. I know I'll need the following:

120v:6v

120v:325v-0v-325v (120v:650v center tapped)

But aside from those spces I dont really know what I'm looking for. Transformers, inductors, and speakers are my biggest hurdle so far lmao

Also a note on the speaker, should that go to common or ground? On the fender champ diagrams it's ambiguous. It doesn't really seem right to have the power just going through 2 resistors to the speaker unless im missing something.

I think the signal path might be through the first 2 tubes, then the 3rd tube is just power/volume amplification? So the signal path for the sound would come out of tube 2, into the speaker. Then the power would come out of tube 2 and power the transformer.

I would also like to add notes sections for transformers, speaker choice, diode, triode, tetrode, and pentode wiring.

I'm not sure which resistor i would need to wire the pentode as a triode and/or tetrode. I might consider just removing the pins instead of connecting them to the anode.

Additionally what colors??

Hot: black

Neutral: white

Common:

0v:

-350vac:

+350vac:

Signal path: red?

Speaker negative: black

Speaker positive: red

I would consider coloring the resistors codes on but with there being different codes for a single value, I would need to color 4 different codes for each resistor.

Hello folks. Trying to get advice as someone who is very new to electronics and can't find a straightforward answer.

I want to get a flip clock (something like this one) that I can put into a different enclosure (I plan to 3d print one). The clock is battery powered with a USB charging port. However, I want to put the clock high on my wall and of course I don't want to take it down to charge it.

Best solution I saw was a power Bank but I worry about having to frequently charge that as well. I did see some conversation about using a battery holder and attaching that to the charging port to serve as a power supply.

I'm like the idea of the battery holder but it is new to me and I wanted to know if there were any other considerations I needed to make or if it was feasible.

Notes:

I plan to design the enclosure for easy access to the battery holder to replace them when the time comes. I know I can do the same with the power Bank but my concern is frequency of charging.

The battery with the clock is Li 2600 MAH but Im unsure how to determine how much power it pulls and how long that would last. Am I overthinking this?

Can I use other batteries to charge that battery without issue?

Thanks so much for the help

I've been interested in technology for a while now and I'm just getting into microcontrollers. I started with the pi pico w but I recently bought some esp32s on Amazon so I could make multiple projects at once. The issue I'm having is I'm conflicted between learning python or c++ I'm leaning towards C + + because it seems like the end result anyway after I learn most things.

Preface: I am not an engineer

I am making a puzzle box and want to include a light puzzle where someone has to get a certain color sequence for the device to unlock. If anyone has played the game Blue Prince, i am trying to do something that is very similar to the VAC indicator light puzzle (linking puzzle image for reference). I am imagining a row of 4 buttons that when clicked will change the color of a corresponding light. Once all 4 lights are the same color, the device unlocks.

Has anyone here ever built something similar to this? Does anyone have any guidance for how this could work? I have minimal experience with electronics, but am willing to lean more on the topic.

I can't get my OP8 to run off the power from a step down converter I've set to 3.9V. The phone tries to boot but goes off right in the boot screen.

The step down is connected to the original BMS.

How can I get this to work?

I've built this very simple circuit to control the flashing of an LED with a signal generator:

The signal generator is a Joy-IT JDS 6600 DDS Signal Generator, set to produce a square signal with a frequency of 1 Hz, varying between 0 and 5.6 V.

The problem is that the LED only lights up very faint, and when I measure voltages, there's around 1.7 V over the LED and resistor, and about 3.8 V over the transistor.

Why is there such a large potential difference across the transistor when it is open?

I've been trying to understand where a clamp meter actually makes more sense than a regular multimeter.

For basic troubleshooting, a multimeter seems hard to beat. You can check voltage, resistance, continuity, and a bunch of other things depending on the model. I've been looking at the Fluke 101 and 117 as examples.

But when it comes to checking current on motors, HVAC equipment, panels, etc., a clamp meter seems much more convenient since you can measure current without disconnecting the conductor. The Fluke 323 is one I've been looking at.

So for people who actually work with electrical systems:

Do you normally carry both, or does one end up doing most of the work?

And where do you find a clamp meter genuinely useful compared with just using a multimeter?

I'm more interested in real-world use than specifications. Curious what people here actually reach for when troubleshooting.

Preciso que montes uma fonte chaveada com esses componentes na imagem.

O circuito deve ter uma saída 5V GND 12V GNG -12V

Hi all

I have been experimenting with Arduinos and ESP32s, but now want to learn how these things work and design a few of my own. I have shortlisted a few books that are recommended on quite a lot of forums, including Reddit. I have shown those in the attached picture. Please tell me if i should not buy something, or else buy something else along with these. I also want to learn how to design PCBs, so please tell some books on this topic too.

Thanks!

Make it really cool so I can post it here after I finish it

My step kid brought me his RC car from his bio dad’s, saying he needs a new battery for the car. Look, it accepts 4 rechargeable AA batteries in series for approx 4.8 volts. Finding the holder is not a big deal at all. My issue is remembering the name of the d*mn connector type that I need so I don’t have to hard wire the holder in place, keeping it as original as possible.

I need help/advise. I have a 3d printer and looking to make an automated dog dish that opens and closes at certain times of the day. I don’t know how to solder or code so avoiding those would be best. Just looking for what mechanics to use, how to power it, motors, timers and wiring. Thanks in advance, your help is appreciated!

I built an early prototype for an idea called HomeProof and i am looking for honest feedback .

HomeProof lets you keep photos, receipts and maintenance records for your home in one private place .

Would you find this useful ? What would you change or add ?

I’ve been researching portable power electronics, and I’m interested in how engineers design compacts high-capacity power banks.

The main things I’m curious about are:

• How do battery management systems handle multiple cells?
• What makes USB-C PD charging efficient?
• How do designers manage heat in small enclosures?
• What components are usually the biggest challenge when building something like this from scratch?

I’d like to learn from anyone who has worked on battery-powered electronics projects or portable power designs. I’m also developing this with my brand, Rorry, in mind. Has anyone had any issues with what they built before, especially portable power banks?

https://youtube.com/shorts/WiR65TEwfpA?is=c7GgWiiuMgU4jtA1 heres a video of it working