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Best methods to learn how to fix and build radios?

  1. Jan 10, 2015 #1
    I was thinking that a good way to learn a lot about basic radios and other non integrated circuit electronics would be to take them apart and fix the connections with a scoldering iron and a multimeter. My goal is to understand how radio circuits work so I can build them and fix them. Any comments on what you think of this approach would be appreciated.
     
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  3. Jan 10, 2015 #2

    Doug Huffman

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    It is the traditional approach, but not so easy now that IC are universal. My first radio transmitter was a seven foot tall Collins Kilowatt KW-1.
     
  4. Jan 10, 2015 #3

    anorlunda

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    As learning instruments, vacuum tube radios were superior. It may be difficult but not impossible to find some to tinker with even today. I wager that there must be support forums on the Internet for that.

    By the way, Richard Feynman once famously fixed a radio by pulling the tubes and putting them back in reverse order.
     
  5. Jan 10, 2015 #4

    nsaspook

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    Go to your local thrift stores and buy old electronics castoffs if you want to understand mechanical construction and repair. Just poking around with a multimeter won't gain you much electronic knowledge about the fundamentals of radio operation, design and repair. You can reenforce book learning by this but it's not a substitution for it.
     
  6. Jan 10, 2015 #5

    Baluncore

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    I would suggest that you find a local amateur radio operator or group. Getting an old edition of the ARRL handbook would be a good move, it could come from a second hand bookshop or a local amateur radio operator.
     
  7. Jan 10, 2015 #6

    Doug Huffman

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    Nothing good happened with the relaxation of licensing requirements into commodities.
     
  8. Jan 10, 2015 #7

    Baluncore

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    Relaxation of the entry requirements has not actually hurt the amateur community or “service”. If anything, relaxation has given it a reprieve from some band cancellations.

    There was a time pre-WW2 when CW speed was the only important entry requirement. Following the technical training offered by the services during WW2 the technical competence of operators increased. Unfortunately the post WW2 entry requirements remained artificially high and required significant experience before entry into the field. That was a significant barrier to new membership.

    The expansion of an interest in wireless technology requires books on the subject, junk radio gear, used test equipment and knowledgeable people to answer questions. Here on PF we can answer the questions, but the rest should come from the pool of books, junk boxes and deceased estates looking for a home. That is best found through what remains of the local amateur radio community.
     
  9. Jan 12, 2015 #8
    Find an old oscilloscope on ebay, and learn to use it. Learn to read a schematic.
    I showed my Son, without much trouble while he was learning to work on guitar amps.
    Some of the old Schematics show what the signal should look like at different parts of the circuit.
    If you have not done so, a basic analog electricity class would help. (I am not sure they still teach that)
     
  10. Jan 12, 2015 #9

    Bandit127

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    It's a good job that analog electronics are required to make digital work.

    I would agree with the sentiment of a lot of responses on this thread. The OP needs to find a group of people who can teach and mentor, either formal or informal. Self teaching electronics is going to be a slow slog.
     
  11. Jan 17, 2015 #10
    I found this channel on Youtube I think it is very good:https://www.youtube.com/user/AllAmericanFiveRadio
    I will try to learn how to understand circuits through that channel and hands on experience with circuits and of course wikepedia. Thank you for all the great respones!
     
    Last edited: Jan 17, 2015
  12. Jan 17, 2015 #11

    jim hardy

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  13. Jul 27, 2015 #12
  14. Jul 27, 2015 #13

    jim hardy

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    It is a wonderful textbook on tubes and analog circuit analysis.

    You will learn what voltage to expect at every point in a circuit.
    Tubes have pins that are big enough you can get a voltmeter probe onto them.
    Today's IC's have such teensy pins so close together it's hopeless for a beginner to work with them. I have to use a sewing needle and magnifying glass...
     
  15. Jul 27, 2015 #14
    Vacuum tubes are pricey but I agree.
     
  16. Jul 27, 2015 #15

    Nidum

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    Do it backwards .

    There are large numbers of electronic kits available from trivial to complex . Put some of them together and learn as you go .

    Similarly put together some electronic circuits from hobby electronic books .

    There are also school and college level electronics learning systems with a pack of components , breadboard and (usually) good teaching material .
     
  17. Jul 27, 2015 #16

    Nidum

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    Purely as a bit of nostalgia - my first ever experience of electronics was making a crystal set .
     
  18. Jul 27, 2015 #17

    berkeman

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    Me too! I was about 8 years old, I think, and I still remember Dad helping me string the long antenna wire across the side yard... :smile:
     
  19. Jul 30, 2015 #18

    davenn

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    Me 3 :smile:

    Seems so long ago .. was also around 8 - 10 yrs old.
    Dad knew nothing of electronics, it was with my Grandad and my summer holiday visits there that I learnt about such things

    Dave
     
  20. Jul 31, 2015 #19
    You may have found all the infomation you wanted Sorry I just joined up an could recommend the following,

    There are a number of Ham web pages on the internet. I think that K7QO.net is an excellent choice. His Lab book is an great source for learning. Also the ARRL Handbook is a great learning tool.
    The All American 5 really refers to using 5 tubes for the set. Those tubes are hard to get today. Most are made in Russia. You can find some at a Ham Swap meet. The old radios are hard to find and getting a schematic may be harder.

    There a number of places to get the manual but are getting harder. Chuck (k7QO) may have some tube stuff but you will have to look.
    I had a Yaesu 101e that had a old TV Horizontal output tubes for a final amplifier the cost was about 7 or 8 dollars each. The last time I checked they were 45dollars maybe more.
    If your interested some of the ham gear tube type look up "boat anchors" usually refers to the weight due the weight of the transformers.
    Good luck and fun.
     
  21. Aug 2, 2015 #20
    Before you go getting too deep into obsolete vacuum tube stuff, I recommend "Solid State Design for the Radio Amateur" by Hayward and DeMaw. A pretty good introduction to how to think about analog transistor circuits in the way that those who design such things think about them - as opposed to textbook thinking.
    I don't think it's in print any more, but you can find used online.
     
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