Electronic hobbies and discussion

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Hi all, my name is Randy and I'm a dirtaholic.

Okay, I'm thinking about utilizing this thread to promote electronics learning for IFS members kids that they can build at home for fun projects and learning. I started putting things together at around age 8 or so and made my first car using an Erector Set that my dad got me for Christmas. My brother made fun of it and called it stupid and I remember my dad yelling at my brother. Anyways, my little electric car worked.

My point, it inspired me to keep on doing what I liked and I hope some IFS members get interested in some of these projects and do them with their kids. They will be pretty simple and I will even draw simple schematics and explain.

Finally, the OP and posts#'s 2-6 will be used for future use/resource information... at least that is the current thought process and it may change a bit as I constantly add content to this thread.

For now, post# 2 will be a simple LED circuit. So, hopefully read on and I hope you enjoy? :noidea: Again, things will likely change as I add on...

I'll start:

This is actually more "work related" and is a simple VU meter that also will display voltage and current on the LCD display. I plan on doing something similar for other ideas I have that is hobby related.

Anyways, here are the pictures:

My custom preamp, voltage regulator, and potentiometer all on a single board made to attach to a solder-less breadboard. The battery snap is there to make it easier to connect to either a 9V or an actual power supply. I mounted the components upside down to make it easier to probe the board if needed, which I did on occasion and glad I came-up doing it that way.
IMG_20190205_155635.jpg

IMG_20190205_155501.jpg

My Arduino Uno using it to develop my project. Some people don't understand the concept of a demo board. In short, you use it to test your code.
IMG_20190205_155148.jpg

My A2D converter in my code is working.
IMG_20190205_155119.jpg

Now, below are pictures of transitioning the microController and such over to what will eventually become "the final product" and ready to use. It simply shows how much "output level" by raising a certain number of LED's accordingly. It will display voltage used as well as current draw. I still have to write the code for the current draw part and some circuitry to my board. I left a second analog pin on the board for "future use" and that future use is already here. HAHAHAHA It was an "after the fact" thinking and is the reason why I try to plan ahead for such situations for future ideas.

Anyways, showing the "main board" connected to the 16x2 LCD display. The switches, potentiometer, and green LED are the ON/OFF, display brightness, and "heartbeat" LED indicator, which the heartbeat LED indicator lets me and/or the user know that the microController is running.
IMG_20190315_154722.jpg

IMG_20190315_154833.jpg

Close-up pics of the main board and LCD display. The LED's for the VU meter aspect are to be mounted on the right-side of the display. The chip with the green sticker is my microController with my custom programming.

The bigger 28pin chip on the right is a voice chip, but there is nothing on it yet, but wired in and almost done. I still have to add the circuitry for the analog input and output.
IMG_20190315_155413.jpg

HAHAHA, ALL custom cut parts layout with wire harness/cable management. :rofl::rofl::rofl:
IMG_20190315_155018.jpg
 
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Joined
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A very simple LED circuit to get started with... Once you get a grasp of doing this, it's not too difficult to build very simple circuits.

Explanation:
To get it to work and not draw too much current, you need the resistor. In order to get the approximate correct resistor value, certain parameters need to be taken into account/given. Say you have a 9Vdc battery, various resistor values, some wires, and a RED LED (NOTE: typically a RED LED will light full illumination at roughly 2V @20mA... other colors and LED types can vary in voltage and current draw values).

Set some parameters given what is typically known. So, we know that we want a current flow of approx. 20mA to flow through the LED to make it light up, we know what voltage value is needed to light the LED, we just need to find our resistor value? That's it.
SimpleLED_circuit.jpg
 
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I finally disassembled my laptop, a Toshiba Tecra A11, which is definitely old by today's standards for sure. I don't need hardcore computing power with the type of stuff I do. It is however slightly upgraded.

Anyways, a couple years back a glass of milk fell over and splashed on the desk and partly on my laptop. Needless to say I was pretty damn upset, but I was able to take the HDD out and recover whatever programming files I had done.
IMG_20201218_150316228.jpg

The laptop did work, but not too long after it wouldn't boot and just have a flashing light that, when I looked it up typically meant a power issue. I did everything possible to fix it by taking the battery out, different power packs that are the same, but for my other older Toshibas, etc.

Main boards are pretty cheap so I'm saving money by just replacing the main board, which is highly likely the issue.

I'm just going to replace the board and use this laptop for my astronomy setup that I WAS starting to configure and it was working, but then the milk incident happened. :doh::headwall:

I've replaced laptop boards before and even upgraded the processors in them by mixing and matching pieces/parts. They were older Toshiba Satellite Pro's of various configurations that I had aquired from my old job.

Anyways, just wanted to share and say that most of your laptops from my personal experiences are fairly simple to fix... even the screen.
 
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4runner DOA

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I finally disassembled my laptop, a Toshiba Tecra A11, which is definitely old by today's standards for sure. I don't need hardcore computing power with the type of stuff I do. It is however slightly upgraded.

Anyways, a couple years back a glass of milk fell over and splashed on the desk and partly on my laptop. Needless to say I was pretty damn upset, but I was able to take the HDD out and recover whatever programming files I had done.
View attachment 31710

The laptop did work, but not too long after it wouldn't boot and just have a flashing light that, when I looked it up typically meant a power issue. I did everything possible to fix it by taking the battery out, different power packs that are the same, but for my other older Toshibas, etc.

Main boards are pretty cheap so I'm saving money by just replacing the main board, which is highly likely the issue.

I'm just going to replace the board and use this laptop for my astronomy setup that I WAS starting to configure and it was working, but then the milk incident happened. :doh::headwall:

I've replaced laptop boards before and even upgraded the processors in them by mixing and matching pieces/parts. They were older Toshiba Satellite Pro's of various configurations that I had squired from my old job.

Anyways, just wanted to share and say that most of your laptops from my personal experiences are fairly simple to fix... even the screen.

By the time my laptops die, I'm due for a new one so I usually just replace. I've never actually bought a high end laptop though because I'd rather put my money into my desktops. Currently in a dilemma of I'm ready to replace both, but now I have my work laptop for casual stuff so I'll probably start saving for a new desktop setup.
 

Stairgod

Two bad decisions away from buying a bulldozer
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A very simple LED circuit to get started with... Once you get a grasp of doing this, it's not too difficult to build very simple circuits.

Explanation:
To get it to work and not draw too much current, you need the resistor. In order to get the approximate correct resistor value, certain parameters need to be taken into account/given. Say you have a 9Vdc battery, various resistor values, some wires, and a RED LED (NOTE: typically a RED LED will light full illumination at roughly 2V @20mA... other colors and LED types can vary in voltage and current draw values).

Set some parameters given what is typically known. So, we know that we want a current flow of approx. 20mA to flow through the LED to make it light up, we know what voltage value is needed to light the LED, we just need to find our resistor value? That's it.
View attachment 31131
So if I want to use 12v LEDs using an 18v power source I just need to splice the appropriate resistor inline? How do I go about finding the miliamp draw of the 12v lights in question?
 
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By the time my laptops die, I'm due for a new one so I usually just replace. I've never actually bought a high end laptop though because I'd rather put my money into my desktops. Currently in a dilemma of I'm ready to replace both, but now I have my work laptop for casual stuff so I'll probably start saving for a new desktop setup.
If you can get away with using your work laptop for now, I would start saving for a desktop setup. :thumbsup:

Have you ever gone to "MicroCenter"? :noidea:
 
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So if I want to use 12v LEDs using an 18v power source I just need to splice the appropriate resistor inline? How do I go about finding the miliamp draw of the 12v lights in question?
Pretty much, but you will need to know what the acceptable current draw of that module is and then you can go from there on what resistor value you will need.

Probably safe to say to assume 20mA and work from there.

So, R=(18-12)/0.020=300ohm and make sure to use 1/4W resistor too or higher if you can, but a 6V drop and only about 20mA of current shouldn't get all that warm, if at all.

Sometimes, in certain situations like your LED thing, you can use a variable power supply, if you have one, start from approx 0V and start raising the voltage level until you start seeing the light(s) light up, while observing the current draw. You can do that method without having to use a resistor, but you should still be careful if you were to do it this way. I have a variable supply at work and for whatever the case may be, I would do just that and/or similar.
 
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Stairgod

Two bad decisions away from buying a bulldozer
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Just checked the specs on the LEDs and they claim 8 watt draw from 12-24 volt. Supposedly they are good from 8-30 volts so I may not need to add a resistor after all.
But how can the wattage be the same regardless of voltage? I have no clue how LEDs work in detail, but that is completely not how any electric motors that I know of work.
 
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Just checked the specs on the LEDs and they claim 8 watt draw from 12-24 volt. Supposedly they are good from 8-30 volts so I may not need to add a resistor after all.
But how can the wattage be the same regardless of voltage? I have no clue how LEDs work in detail, but that is completely not how any electric motors that I know of work.
Electric motors are a bit different, if you will. AC motors I'm not very familiar with at all. DC motors I'm more familiar with, but you have to be careful on how your circuit setup is as they have a tendency to draw higher current than most other things. I really don't know how else to explain that one.

Anyways, yeah, you probably don't need a resistor then if those are the specs? Plus, if it is an 8W draw, then it is obvious to me that there is a resistor setup for however many LED's are in that thing and the whole unit itself is drawing that much, of course.

In either case, it doesn't sound as if you need any resistor in place.
 

4runner DOA

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If you can get away with using your work laptop for now, I would start saving for a desktop setup. :thumbsup:

Have you ever gone to "MicroCenter"? :noidea:

Yeah I know microcenter. I used to buy all my stuff at fry's, but I usually stick to newegg now. Work laptop works for casual stuff, that's all I need it for since it's taking up my desk right now anyway.
 

Chris In Milwaukee

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I have some vintage hifi equipment I bought new in the 80s while stationed in Japan. It’s been sitting unused for a while and I know the pots are dirty at the least and there’s something wrong with the output power meter needle circuits on the amp. Maybe a fuse, maybe more. Thankfully I found a site called HiFiEngine.com that has service manuals for damn near anything. Found the service manuals for my amp and CD player which should prove useful. Now I have to make sure my o’scope still works. Lord knows where the probe is. I miss electronic projects!

Looking forward to getting things cleaned up and running again. It’s been too long that I’ve given in to maybe-adequate music in my house. Sure would love to get the stuff set up and start listening with a seriousness. Gotta get my old vinyl out and cleaned up.
 

4runner DOA

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I have some vintage hifi equipment I bought new in the 80s while stationed in Japan. It’s been sitting unused for a while and I know the pots are dirty at the least and there’s something wrong with the output power meter needle circuits on the amp. Maybe a fuse, maybe more. Thankfully I found a site called HiFiEngine.com that has service manuals for damn near anything. Found the service manuals for my amp and CD player which should prove useful. Now I have to make sure my o’scope still works. Lord knows where the probe is. I miss electronic projects!

Looking forward to getting things cleaned up and running again. It’s been too long that I’ve given in to maybe-adequate music in my house. Sure would love to get the stuff set up and start listening with a seriousness. Gotta get my old vinyl out and cleaned up.

Flac sound files and a quality digital sound system can do some amazing things. I'm still using my old portable bose system when I really want quality sound.
 

Chris In Milwaukee

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Flac sound files and a quality digital sound system can do some amazing things. I'm still using my old portable bose system when I really want quality sound.
I just started a trial sub to Qobuz. Holy cow, the stuff they have sounds amazing just through my desktop computer speakers. Can’t wait to go bigger again. I’ve been reading a lot about high resolution streaming/lossless media over the last week or two and I’m ready to dig in. Easy to get in for little cash outlay. Need to invest in the digital side a bit.
 
Joined
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Flac sound files and a quality digital sound system can do some amazing things. I'm still using my old portable bose system when I really want quality sound.
I just started a trial sub to Qobuz. Holy cow, the stuff they have sounds amazing just through my desktop computer speakers. Can’t wait to go bigger again. I’ve been reading a lot about high resolution streaming/lossless media over the last week or two and I’m ready to dig in. Easy to get in for little cash outlay. Need to invest in the digital side a bit.
The one thing that I like about desktops is that you can typically upgrade them to more updated stuff... to a degree of course. But, my point being is that if you don't need high end computing "power" for any latest games, if you do any gaming, then completely upgrading doesn't make any sense if you don't need to. Laptops though, once you buy a laptop, there is very, very little you can do to "upgrade".

I like how "gaming laptops" are all hype. Not saying they aren't any good or anything, but paying that kind of money and roughly 6months to a year later it is pretty much outdated and not really anything you can do to upgrade it.
 

4runner DOA

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I just started a trial sub to Qobuz. Holy cow, the stuff they have sounds amazing just through my desktop computer speakers. Can’t wait to go bigger again. I’ve been reading a lot about high resolution streaming/lossless media over the last week or two and I’m ready to dig in. Easy to get in for little cash outlay. Need to invest in the digital side a bit.

I can run flac through my pioneer head unit in the 4runner, but most of the stuff I have I already downloaded in lesser formats because I never wanted to deal with flac. Haven't had a quality music torrent site since what.cd went down (I had oink before that) so it's been a few years. Now I rely on streaming and it's not quite the same.
 
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