[Neo6425]

My neighbor is a kindly older fellow who has always been quick to lend a helping with whatever projects I have going on and, best of all, he has every tool imaginable and is quick to lend it out to anyone in the neighborhood. He is also not shy about sharing his advice in all matters – including my restoration of my Philco 620. Since my workbench is in my garage, and I usually work with the garage door open, anyone walking by can clearly see what’s on my bench, including my neighbor. Now due to social distancing he didn’t step into the garage but he started a conversation that he used to be a HAM radio operator when he was younger and his father, who was in the Signal Corp during WWII, gave him his old Army manuals to read and that how he learned about electronics and radios. He said that I shouldn’t be content with swapping out parts, that I should actually learn the theory behind how the radio works. 
He said this as I was removing a 30-2079 cap  [Image: http://www.ispdi.com/Philco/images/30-2079.jpg] , because I said to him I know this is a capacitor but I am not really sure of its function in the circuit. The next morning on my doorstep there’s a manila envelope and inside is the “TM 11-242 War Department Technical Manual Radio Set SCR-300-A SCR1945”. The note attached says, “If you plan on working on radios, especially old ones, I want you to read this US Army Manual first.” (I found a PDF of a later edition of this online and I’ll share it here if anyone is interested in taking a look. - Radio Set SCR-300-A )

So here’s the reason I’m writing. I feel fairly confident I can switch out parts from my chassis and get this radio to work. Yet, I would really like to learn more about how a radio works and better understand its electronics. My neighbor really made think about what it is I hope to accomplish by restoring my radio and I realized I don’t want to be just a “parts swapper”.
These past few weeks I have been exploring books on the topic and looking at Army manuals (thanks to my neighbor) that were used to teach soldiers basic electronics and I’m confused which path to take. So can anyone recommend the best way for me to learn radio repair on my own? I can’t afford to go back to school and I am hoping someone can recommend a way I can start this journey.

[John Bartley]

Back in the 1950's (roughly), the U.S. armed forces produced a set of hard cover training books, a set of three in one cover, titled, "Basic Electricity, Basic Electronics, Basic Radio" There are others that are also good, but this set, authored by (as I recall) VanValkenburgh sp? is the absolute best I have ever seen for learning on your own. It's probably my most read, most used for reference book set. I tink it's available on line for free if you search.

That book was what taught me almost everything I learned about theory.

Have a look : https://archive.org/details/BasicElectro...umes151955

https://archive.org/search.php?query=cre...Neville%22

[Neo6425]

John,
I just took a quick glance at those links and they look fantastic! You can be sure I'll be reading them closely later today when I finish up my "Honey-do" list today.
I really appreciate your help!
Thank you!

[Brad Winder]

Good that you want to learn!   There are many beginners I meet, that just want to "make it work" without understanding any theory behind their radio, or knowing what the components they are changing actually do.

I read a lot, but I know that's not everyone's cup of tea...used to be the only way to get most information. I recommend a combination of reading vintage books, plus some more modern ones (that explain many things in today's terminology) and using the internet. Here's some recommendations from me:

1) Book: Drake's Cyclopedia of Radio and Electronics. There are many different editions of this book; best to find a later version with updates. It list terminology from the 1920's to the 50's, and explains what each means, and how each works in circuit.

2) Book: Antique Radio Restoration Guide by David Johnson. A great book for starting out understanding radio and repairs. Puts most explanations in plain terminology.

3) Net: Mr. Carlson's Lab on Youtube. Paul Carlson is an instructor like no other. He explains everything he does, in a way most can understand. And he does everything step by step. His videos are from a half hour to a couple hours in some cases. And he has a soothing voice! Most people seem to be binge watching his channel during this virus isolation. 

[Radioroslyn]

And they have swell pictures too!!

[Phlogiston]

You will find that working on electronics is a lot more fun when you know what you are doing - and a lot cheaper, safer and less frustrating.

[morzh]

....and it always easier, when you know what you die from.
© My grampa to the stewardess when flying during bad turbulence.

[Tim Tress]

A couple of old chestnuts that haven't been mentioned are "Elements of Radio Servicing", by Marcus; "Radio and Television Circuitry and Operation", and it's companion volume "Radio and Television Servicing and Repair" by Ghirardi. Another one by him, very dated but thorough, is "Radio Physics Course". The old NRI course books are also very good; I studied them 55+ years ago.

[462ron]

On the American radio history .com there is a page with more electronics study courses and other books on radio theory, more than you could read in a lifetime!   
www.americanradiohistory.com/Home_Study_Courses.htm 

Ron

[Neo6425]

I want to thank everyone for their input on how to better understand Electricity & Electronics. I decided to use  Basic Electricity: Complete Course, Volumes 1-5 1st Edition by Van Valkenburgh (Author), Nooger (Author), Neville (Author). It's an older book for sure and I've been told some items are "dated", but overall, I feel it's a great book for someone like me.

I am still on the 1st volume and have a question regarding the direction of current flow.
According to the electron theory; current flow is always from a (-) negative charge to a (+) positive charge. So my understanding is if a wire is connected between the terminals of a battery, current will flow from the (-) terminal to the (+) terminal.

However, I have always thought of direction of current flow in what is called the "conventional current flow". In repair/rewiring cars and trucks I have always thought of current flow in this way. So here's my dumb question. Is there any problem learning the electron theory and not conventional current flow? Everything in my book is all electron theory and I am a bit concerned if this will be a problem goining forward. Or am I missing something?
If I sound confused, it's because I am.


[Image: http://www.ispdi.com/Philco/images/ETheory.JPG]

[Eliot Ness]

It shouldn't be a problem and you'll probably find as many proponents supporting electron flow as you will conventional current flow.

You know, I've completely rewired at least three cars and installed an AC unit in one, and not once did current flow really cross my mind. Positive and negative polarity did, but not once can I recall trying to sort out what direction the electrons or holes or whatever were flowing.

My advice is to pick what theory makes the most sense to you and stick with it for the sake of theory, although since your course is going to be constantly referring to electron flow that would probably be the one I'd choose. And just to ease your mind, no matter which theory you espouse, the radios and cars you work on will still function the same

[Neo6425]

Thanks Eliot Ness! I truly appreciate your input. I tend to "overthink" items, so I appreciate your advice.