# beginner

1. ### Heart Rate Alert System

Hello, I am pretty much new to Digital Circuits, I am having difficultly design this Heart Rate Alert System I got as a project. I am pretty much confused I was able to create like a simple alarm system that accepts the input of 3 sensors, if 2 of the 3 sensors are on it will trigger alarm...
2. ### Thevenin's Theorem

Hello, I am new to solving things using Thevenin's Theorem and I am getting very stuck on a problem. I completed 5 other ones in no time but this one just seems to stump me. I have a program where I can check my answers after drawing out the circuit and I have no idea how to get the numbers...
3. ### 8051 need help with code:CCC

So hello:3 I have already tried many things, and looked at many things, but I can't implement any way to read a value from my data table character by character here code: Morse: mov DPTR, #Text ; Point to the beginning of the text mov...
4. ### first ever pcb design (beginner)

Hello I've been using breadboard for years . few weeks ago i found some nice deal on MT3608 ( a step-up switching ic) and want to use it in some project and so is the first pcb that i have made very sloppy following project is a part of another one i am not very sure how to rout switch node...
5. ### Boost converter design issue

For a circuit I'm designing, I want to use an MC34063AL-D08-T DC/DC converter (or a similar one; I just need a through-hole package) as a boost converter to boost a voltage $$V_{in} = 3.3-4.2 V$$ (coming from a Li-ion battery) to a stable output of $$V_{out} = 5 V$$, with \( I_{out} = 250 mA...
6. ### How do I make an Equipment ground

I am building the Elenco AM/FM radio kit. And for a static power test it is telling me to connect my equipment ground to circuit ground test point 15 while the circuit is being powered by a 9volt battery. . I’m just pretty confused on what it means by “equipment ground” and what I can do to...
7. ### Other methods of converting a pushbutton switch to a latching/toggle switch (Zero power if off)

It's been days since I have been on this quest of making the pushbuttons that come with a electronics kit I bought to a toggle switch and although I have achieved it by using a NE555P IC Timer, I am not liking how it still consumes power even when the whole circuit is intended to be off. I am...
8. ### Clock edge detector using capacitor and resistor problem

I have watched recently this video: At the end of it he describe a way to make edge detector by using capacitor and resistor. The thing is i don't see it being discharged in any way. Would't it make it impossible to charge again and in consequence make current flow through the resistor and make...
9. ### Beginner's question about a NOT inverter

Hello, This is my first post here. I'm trying to learn electronics on my own via different sites At the moment, I'm trying to understand how a NOT inverter works. I perfectly understood what it was used for, but something escapes me on this diagram...
10. ### 12v DC 7A UPS from Li-ion Batteries

Hi All, Complete beginner here so please bear with me! Trying to work out a solution for changing the main battery on my portable video switching system. The project is powered off a single 12V DC 8A V-Mount battery which powers the system perfectly. That said, I can't find a UPS with the...
11. ### How to find a mistake. Sound amplifier circuit board. Need help with troubleshooting

Hi, I bought DIY amplifier board. And now I am trying to find what I did wrong. It can work for about 2 seconds and then sound dissappear. But power stays on, and LED is glowing I connected 24 volt toroid to start the board. In description it says that circuit is designed for 12 to 36 AC...
12. ### Trying to design an audio circuit with a carbon single button microphone so that I can output the audio into a PC

So I recently purchased a 285W western electric transmitter as I'm trying to more or less make a microphone that can plug into a computer which uses a carbon button microphone from the early 20th century. I have little education in circuit design, though I know enough to know I probably made...
13. ### What is the best book to start learning about electronics?

I'm 15 and want to start learning electronics but I don't know what the best book is for beginners. I have read suggestions on other sites and there are 2 books that keep coming up. "The Art of Electronics" and "Practical Electronics for Inventors". What would be the best out of these two? Or if...
14. ### How to select appropriate components?

I've just started tinkering and I'm having trouble with a pretty basic concept: reading and selecting components. I have some push buttons that say ACDC 24V — does this mean in need 24V of AC -> DC power for the component? I have another push button that says: UI: 440V AC15 Ith: 10A DC13 —...
15. ### Adapting an old CRT Viewfinder ( 9.3 V DC / 2.7W )

Quarantine project: Adapting a Sony BFV-20W viewfinder Scroll down to skip the background info As a cinematographer, I've always really felt most comfortable shooting with a viewfinder. However modern electronic viewfinders all exist in the "prohibitively expensive" class of filmmaking...
16. ### "Control Panel" Play Station — How?

Let me just state: I'm a totally newb (some entry-level Arduino and breadboard tutorials under my belt) and my vision is vastly outside the scope of my abilities, but I'm here to get some broad tips and feedback so that I can figure out where to begin on my path towards actualizing this project...