Help an old geezer understanding today's electronics

Thread Starter

Old Bear

Joined Feb 28, 2021
5
A quick background: self-studied electronics in mid-60's. Took one DeVry course about same time. I have only dabbled with electronics since.

At 80+, I am trying to catch up. I'm finding the transition from tubes and the early transistors to modern IC's daunting. Everything I find on the internet is how to make the #*?? things, not how to use them. I'm not looking for the theory behind them but how to use them!

My 3 questions are: 1) Is there a resource that will guide me to the correct IC family for any projects? 2) a guide for using them (i.e.: biasing requirements, etc.). Would this be in the data sheets for what ever IC I decide to use? 3) Any recommended books or resources to help bring me into the modern world of electronics?

I would like to start experimenting with them by doing some minor projects for Ham Radio, such as a frequency counter, wave form generator, or a VSWR meter as examples. While there are schematics for such things on the internet, they each seem to use a different IC with no rime or reason for nomenclature, or why the chose a certain value for external components. Or, which maybe the most recent design for such things as extended bandwidth?

Any help appreciated!
 

MrSalts

Joined Apr 2, 2020
2,767
A quick background: self-studied electronics in mid-60's. Took one DeVry course about same time. I have only dabbled with electronics since.

At 80+, I am trying to catch up. I'm finding the transition from tubes and the early transistors to modern IC's daunting. Everything I find on the internet is how to make the #*?? things, not how to use them. I'm not looking for the theory behind them but how to use them!

My 3 questions are: 1) Is there a resource that will guide me to the correct IC family for any projects? 2) a guide for using them (i.e.: biasing requirements, etc.). Would this be in the data sheets for what ever IC I decide to use? 3) Any recommended books or resources to help bring me into the modern world of electronics?

I would like to start experimenting with them by doing some minor projects for Ham Radio, such as a frequency counter, wave form generator, or a VSWR meter as examples. While there are schematics for such things on the internet, they each seem to use a different IC with no rime or reason for nomenclature, or why the chose a certain value for external components. Or, which maybe the most recent design for such things as extended bandwidth?

Any help appreciated!
What's the goal? To communicate with people around the world on ham radio? Or, to say, "I built it and I know what I'm doing and I know how it works". Note that I can operate my TV and Laptop just fine without knowing in detail how the transmitters snd receivers work. Time is ticking and if your goal is to communicate, then you may be better off buying what you need and plug it in.

otherwise, a very good resource for your projects is to ask here. Get pointed to a chip familiar to some or most of us, design a PCB, send the design to China with $15 and get your PCB in a few weeks. Populate the board and fire it up.
 

dl324

Joined Mar 30, 2015
16,839
Welcome to AAC!
1) Is there a resource that will guide me to the correct IC family for any projects?
No. Mainly because there are many ways to do the same thing. You might choose certain parts because you've used them before or because it's one you've never used before and want to learn how to use it.

If you're going to use 5V, 74HC and 74HCT are what's used instead of TTL. If you want a wider operating voltage range, CD4xxx still have good availability. If you're looking for faster, low voltage operation, you'll probably want 74LV.

EDIT: From Texas Instruments:
1675893189627.png
2) a guide for using them (i.e.: biasing requirements, etc.). Would this be in the data sheets for what ever IC I decide to use?
You don't have to worry about biasing requirements for ICs. CMOS parts are mainstream these days and they work with a range of voltages (wider than the 5V +/- 5% for TTL).
3) Any recommended books or resources to help bring me into the modern world of electronics?
Instead of reading books, I'd suggest having a project you want to do and learning what you need to do it.
they each seem to use a different IC with no rime or reason for nomenclature
There are many chips that have similar function (e.g. decade counters). There are some parts that have equivalent, pin compatible parts in multiple technologies (e.g. CD4503 and 74367). Then there are parts like CD4040 and 74HC4040 that are the equivalent parts in different technologies. Though both CMOS, CD has a wider operating voltage (3-18V) and HC is faster, but with a narrower voltage range (2-6V, but sink and source more current). 74HC is more akin to TTL, but the inputs and outputs are CMOS. 74HCT are 74HC parts with inputs that are TTL compatible.
or why the chose a certain value for external components.
That's the $64K question. If you designed the circuit, you should understand all of the considerations that went into selecting values. If you don't, then you're not really designing circuits.

If you're using someone else's circuit, when you can understand why, then you'll be in a position to design something similar.

There seems to be a tendency among newbies to mix logic families. That's not a good idea for beginners. For example, CMOS outputs can (usually) drive TTL inputs, but TTL outputs aren't guaranteed to drive CMOS inputs (though it will sometimes work).
 
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MaxHeadRoom

Joined Jul 18, 2013
28,617
A quick background: self-studied electronics in mid-60's. I have only dabbled with electronics since.
At 80+, I am trying to catch up.
Boy, you have a lot of catching up to do!!
I am an old fart also, but got the exposure as it unfolded! :p
Some books you may want to search for, sources are the likes of AbesBooks.
Howard Sams, is one favorite publisher.
Titles.
Practical Design with Transistors by Mannie Horowitz.
Unique IC OP-Amp applications by W.G. Jung
IC OP-AMP Cookbook by W.G. Jung
TTL Cookbook by Don Lancaster- Sams Pub
ABC's of Silicone controlled rectifiers by Allan Lytel

Once you have caught up, there are the modern day Micro chips that can do wonders in the confines of 8 pins. :cool:
 

MrChips

Joined Oct 2, 2009
30,706
A quick background: self-studied electronics in mid-60's. Took one DeVry course about same time. I have only dabbled with electronics since.

At 80+, I am trying to catch up. I'm finding the transition from tubes and the early transistors to modern IC's daunting. Everything I find on the internet is how to make the #*?? things, not how to use them. I'm not looking for the theory behind them but how to use them!

My 3 questions are: 1) Is there a resource that will guide me to the correct IC family for any projects? 2) a guide for using them (i.e.: biasing requirements, etc.). Would this be in the data sheets for what ever IC I decide to use? 3) Any recommended books or resources to help bring me into the modern world of electronics?

I would like to start experimenting with them by doing some minor projects for Ham Radio, such as a frequency counter, wave form generator, or a VSWR meter as examples. While there are schematics for such things on the internet, they each seem to use a different IC with no rime or reason for nomenclature, or why the chose a certain value for external components. Or, which maybe the most recent design for such things as extended bandwidth?

Any help appreciated!
We have come a long way from knowing how to bias a vacuum tube amplifier. All that design effort has been done by the circuit gurus but it still is useful to know how to do that. Instead, most things today are designed as a "black box". You apply power and signal input and you get output. There is no need to know what is inside the box.

So basically, you decide what you want to do and there is a chip for that, with a selection of a few thousands to choose from.
 

bassbindevil

Joined Jan 23, 2014
824
Forrest M Mims produced some good "notebooks" for Radio Shack in the early '80s that cover the basics of CMOS and TTL.
https://worldradiohistory.com/BOOKSHELF-ARH/Radio_Shack_Books.htm
http://www.zpag.net/Electroniques/Kit/The Forrest Mims Engineers Notebook.pdf
Archive.org also has copies of many old electronics texts. Don Lancaster is another good electronics writer.

"The Art Of Electronics" by Horowitz & Hill is very good; expensive new, but you may find older revisions at used bookstores. Or there's pdfs out on the web somewhere.

Playing with Arduino (based on Atmel flash microcontrollers) is a way to get into "smarter" digital devices. From there it's not a huge leap to IOT stuff using ESP Wifi modules. The programming is largely a matter of finding examples and making a few patches. I made a thing that reads DS18B20 digital temperature sensors, and displays the temperature and the hex id of the sensor on a recycled character LCD surprisingly easily. Total cost under $10; one generic arduino pro micro from ebay, one IIC/I2C interface board for the LCD (converts serial to parallel and provides contrast pot; not essential, but simplifies wiring), free LCD from e-waste, sample DS18B20 from Analog.com
With ESP modules, you pretty much just need to interface them with some I/O watching out for 3.3V to 5V conversions, flash them with Tasmota configured accordingly, and you've got a thing that can be controlled from an app on your phone or by voice from a smart speaker.
 
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Thread Starter

Old Bear

Joined Feb 28, 2021
5
What's the goal? To communicate with people around the world on ham radio? Or, to say, "I built it and I know what I'm doing and I know how it works". Note that I can operate my TV and Laptop just fine without knowing in detail how the transmitters snd receivers work. Time is ticking and if your goal is to communicate, then you may be better off buying what you need and plug it in.

otherwise, a very good resource for your projects is to ask here. Get pointed to a chip familiar to some or most of us, design a PCB, send the design to China with $15 and get your PCB in a few weeks. Populate the board and fire it up.
Or, to say, "I built it and I know what I'm doing and I know how it works".
 

BobTPH

Joined Jun 5, 2013
8,806
You are still stuck in the last century. You did not even mention microcontrollers. Everything I do today uses microcontrollers. I have not used a logic chip in decades.
 

Thread Starter

Old Bear

Joined Feb 28, 2021
5
Welcome to AAC!
No. Mainly because there are many ways to do the same thing. You might choose certain parts because you've used them before or because it's one you've never used before and want to learn how to use it.

If you're going to use 5V, 74HC and 74HCT are what's used instead of TTL. If you want a wider operating voltage range, CD4xxx still have good availability. If you're looking for faster, low voltage operation, you'll probably want 74LV.

EDIT: From Texas Instruments:
View attachment 287142
You don't have to worry about biasing requirements for ICs. CMOS parts are mainstream these days and they work with a range of voltages (wider than the 5V +/- 5% for TTL).
Instead of reading books, I'd suggest having a project you want to do and learning what you need to do it.
There are many chips that have similar function (e.g. decade counters). There are some parts that have equivalent, pin compatible parts in multiple technologies (e.g. CD4503 and 74367). Then there are parts like CD4040 and 74HC4040 that are the equivalent parts in different technologies. Though both CMOS, CD has a wider operating voltage (3-18V) and HC is faster, but with a narrower voltage range (2-6V, but sink and source more current). 74HC is more akin to TTL, but the inputs and outputs are CMOS. 74HCT are 74HC parts with inputs that are TTL compatible.
That's the $64K question. If you designed the circuit, you should understand all of the considerations that went into selecting values. If you don't, then you're not really designing circuits.

If you're using someone else's circuit, when you can understand why, then you'll be in a position to design something similar.

There seems to be a tendency among newbies to mix logic families. That's not a good idea for beginners. For example, CMOS outputs can (usually) drive TTL inputs, but TTL outputs aren't guaranteed to drive CMOS inputs (though it will sometimes work).
Thank you.
 
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