If You Need To Learn About Radio Repair..
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I consider myself to be an "advanced beginner"... I can replace caps, I read a schematic pretty well, I can check voltages. I have some understanding of how the signal travels down the antenna and ends up coming out the speaker. I've done a good job of restoring lots of radios.
But, when it came to actual theory and understanding the details of how a radio operates, I was mostly lost. Other than replacing parts, and checking voltages, I had no real idea of how to troubleshoot a faulty set. If you are like me, when you get stuck and a set just won't work, you search for ideas by reading forums, or asking other people.
So you'd see responses like, "check the by-pass cap in the detector stage", "It's probably the cathode by-pass condensor", "Check the plate decoupling filter in the IF"..
....you read that and go..."hrmmm..ok, next thread".. It's all kind of confusing, but you hope that someday you'll get it. As you read the Electrical section of this site, you think "Man, I wish I was as good as Brenda, Morzh, Mondial, etc..." (too many to name them all)...
I found that there are no web pages, no threads, no forums that really explain it all in common language. ... until..
I bought a book - "Elements of Radio Servicing" by William Marcus and Alex Levy. This book should be required reading for all newbies (and even intermediate hobbyists) . It walks you through each individual stage of a radio, explains how the stage works, how to identify that stage on a schematic and how to troubleshoot that stage. It focuses on using a signal generator as the main troubleshooting tool. I learned more by reading this book than I ever thought I'd know, and this book WILL be an invaluable reference tool, and source of information, in the future.
So, if you've hung in there and read this entire post, go order this book from Amazon. It's the best money you'll spend on the radio hobby.
The artist formerly known as Puhpow! 8)
(This post was last modified: 02-17-2014, 07:54 AM by Jamie.)
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I can echo what PuhPow said. Although I generally do understand in pretty good detail how vintage radio circuits work and how to troubleshoot them, I picked up the book "Elements of Radio" by Marcus and Horton (2nd ed. 1948.). The Marcus is the same as the book mentioned above (which I also have on my bookshelf).
I find "Elements of Radio" even better for the theory. It is written in very
plain language and it is all spelled out without lots of skipped steps or hand waving unlike many modern texts.
In general I find that the older the book the more understandable it tends
to be because of the newness of the subject matter at the time it was written.
Another GREAT book on early Television is "Television Simplified" by Milton Kiver (2nd ed. 1948.) also if you're into vintage TVs.
Herb S.
Ithaca NY
(This post was last modified: 02-17-2014, 08:21 AM by hsusmann.)
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Just an FYI for anyone trying to find the book Elements of Radio Servicing, it is available on-line for free at http://www.antiqueradios.com/archive.shtml
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That is a very good reference and if you're patient they'll show up on eBay or AbeBooks.com at a reasonable prices. These were published from about the 40's - 60's so the later editions cover FM and perhaps transistors. The version I'm familiar with is from 1947.
See the post above for the link to a free 6 part download in PDF if you want to preview it before buying a hard copy.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
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Yes, for all you newbies.......
I have read some and am still confused,
So much to learn and soooo much extra time? Oh wait, hmmm
Maybe I'm just lazy :
Ok enough faces, it is a good book, I have read each chapter twice( Only read 5 chapters so far, Or would that be 10?)
I think my laziness is Morzh and Gregg's fault. They help me too much.
Ok I will shut up now...
Sorry I had to add that last face.
Kirk
Times I have been electrocuted in 2021
As of 1/01/2021
AC: 4 DC: 1
Last year: 6
(This post was last modified: 02-17-2014, 09:40 AM by OldRestorer.)
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Well, I strongly recommend starting from basic theory.
NOT from how the tube radio works, (or any radio, or any device) but how the electricity works. EE called electrical for a reason. Sometimes when trying to help and realizing the person on the other end does not know anything, helping becomes difficult to the point of frustration. Almost to the point pf saying "send it to me, it will take me 2 minutes to do what I have been explaining here for several hours".
Really. Theory rules. Very basic. Very-very basic. One does not have to learn about electric field, induction, dielectric constants or what not, but you do need Ohms law, you need Joule-Lenz law, you need your impedances understanding, AC reactances, that is how a cap and inductance behave etc, and then you go for basic circuitry - trying to understand transistor before you do tubes does not hurt at all, in fact it is good as you could experiment and get a feel of how it works without subjecting yourself to the risk of dying the way they show in the Green mile.
Then you could go and understand radio, amps, generators and such.
I am not sure what good books are as I learned my hobby and then the trade in a different country.
But. If you ever could get your hands on this
Svoren R.A.. Electronics step-by-step. The practical encyclopedia of the young radio Amateur
- this is, although translated from Russian, is one of the beste EVER books written for kids who want to learn electronics, and it used to have tubes in it, then there was a book about transistors etc, and generations of Soviet radio amateurs, hams and engineers grew up cutting their teeth using this very book.
I did too.
And if you stumble once in a while, us more epxerienced folks here, we will gladly help you - we have people with strength in different areas, some know tubes better, some transistors, some are good in general electronics, some are also very good with history of radio and particular solutiuons used over time - it will be our pleasure.
But do your part. Please.
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There are many introductory books on electronics that are just plain wrong, in addition to being wordy and long. The old annual ARRL Amateur Radio Handbooks are about as concise as you can get without over simplification.
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This thread is just what I needed before I stick my fingers where they don't belong.
Still getting parts together for the 90 Lowboy restoration and reading these books will keep me busy in the meantime and you guys from being pestered too much when I finally get around to it!
Thanks for the references!
Dave
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City: Clayton, NC
I lucked out and got a hold of a Navy Basic Electronics Course (circa 1960s) many yeas ago. It provided me with some solid basic info to base all of my later self-taught knowledge.
Agree that there is some bad references out there.. For someone who is beginning to learn electronics this can be at best misleading and at worst a good way to get hurt.
With all the stuff out there today, I'm not sure what to recommend to a beginner. But it should be something akin to the multi-volume basic electronics course that I learned from. Since we work on some pretty dated equipment, I do not think it is a bad idea to get an older QUALITY set of references.
For those of you that are like me, a self taught "technician," (and I use that term loosely and with the greatest respect for you real-deal techs out there), I recommend the following:
1. Practical Radio by Moyer and Wostrel, 1926.
This book is good at helping or reminding you of the basics. It is a
SUPER reference for understanding how the older sets work,
including Renenerative, TRF, Neutrodyne, early Super-hets, and
Browning-Drake circuitry.
2. The Radio Handbook, published by Editors and Engineers Ltd.
(I have the 15th edition, publ in 1959)
This is truly one of the best reference books out there. The first
chapter of my edition is "Introduction to Radio," followed by "Direct
Current Circuits," and "Alternating Curent Circuits."
Thirty-Four chapters later you are instructed on constructing
radio and test equipment.
3. RCA Receiving Tube Manual
Great info about tube characteristics and usage in the pages before
you get into the individual tubes. This is where I got a good handle
on what "mutual conductance" was.
4. Elements of Radio Sevicing by Ghirardi. 1938
VERY good, very detailed info pertinent to sets many of us work on
5. Old Time RADIOS! by Carr, 1991
Another good reference, sometimes he assumes that you are
smarter than you are (read-- me).
6. Practical Radio Repair, by Bintliff, 2009, vol 1 and 2
Walks you through troubleshooting, also other interesting info on
test equipment and different fixtures you can make yourself.
ALSO: There are books out there by Al Corbin and others that I have heard are VERY good......
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Back in the 60s when I first got interested in electronics while still in high school I started reading a home study radio servicing course that my father had taken I think around the late 40s early 50s. It was put out by NRI ( National Radio Institute ). It is rather lengthy but very thorough. I believe it is available on Ebay in CD form very reasonable.
Ron
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I started to take a radio servicing course from NRI about 1980... I finished about half of it but couldn't finish because I was laid off from work at the time and couldn't keep up paying for it. I thought it was pretty good, wish I could have finished it.
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Before vintage radios... My experience with networking and repairing computers taught me about the basics of electronics. For instance, I already knew what a resistor was and how it worked. Same for a capacitor, switches, and basic electrical circuits.
What I couldn't wrap my head around was radio theory. How did the signal come out of thin air and turn into a sound inside the radio? It just HAD to be complicated. Or so I thought. I keep reading and reading and looking for understanding of this complicated process. The more I read, the less I knew..."Theory books" only made it worse...
So, I read "Elements of Radio Servicing"... and it clicked. The problem? What had I missed? That it is not complicated at all. It's very simple. I had known the answers all along, but I never believed it. I am still no expert, but now I get it.
The artist formerly known as Puhpow! 8)
(This post was last modified: 02-26-2014, 11:37 PM by Jamie.)
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There was a series of books published by John F. Rider in the late 1950s and 60s that was based on a series of books created for the U.S Navy, one set is called "Basic Electricity" which I do not have, the other is called "Basic Electronics" which I do have. If you can find one or both of these they would be quite useful, especially for understanding tube electronics. The ARRL annuals can also be useful, as can the first section of any older RCA or G.E tube manual. Elements of Radio Servicing is very useful for actually repairing sets, there is also a companion book that deals specifically with AC/DC sets.
One thing you should learn how to use is a volt-ohm meter, you should also memorize the resistor code and know what Ohms law is for. In spite of what some think you don't really need a lot of fancy test equipment to diagnose most problems with a radio, voltage and continuity tests will find 80%+ of the faults. Unfortunately one common fault can't be found by these methods, that is someone coming along a twiddling with the assorted trimmer capacitors and slugs in the set. So for this you need a good, reliable, and calibrated signal generator, unfortunately the typical two tube EICO and Heathkits jobs you see everywhere for sale are not, at least not without a rebuild.
Regards
Arran
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I have heard that the NRI courses were excellent.
What too many Radio Servicing books do is jump right into details without basic "block diagram" explanations of how a radio works. That is how I got a handle on how the detector circuits work.
Mike, it sounds like the Ryder book(s) were similar to the USN courses I found.
Personally, I am just beginning to research/learn about radio transmitter theory, so that I can eventually get a ham ticket.
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City: Fort Washington, MD
Ta Forbes,
I just got my Ham ticket (Technician) two weeks ago. It was a lot easier than I thought it would be. LDG Electronics gave out free hand-held 2 meter radios to everybody that passed the test.
You can take practice tests online as often as you like until you feel confident enough to take the test and then go for it! You'd be surprised as to how much you already know. Check it out. E-ham.net has the practice tests and QRZ.com does too. With QRZ you'll need to register (free) but not at Eham.
The current question pool expires sometime in June or July. After that there will be a new set of questions. If I remember correctly there are 392 total questions but only 35 on the exam. You need to get 26 right to pass.
You can do it!
Dave
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