What was the first circuit you replicated yourself or created that kept you going?

Discussion in 'General Electronics Chat' started by Rolland B. Heiss, Mar 5, 2015.

  1. Rolland B. Heiss

    Thread Starter Member

    Feb 4, 2015
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    Being a beginner basically with a whole lot of curiosity not knowing really where to place that curiosity I figured it would be wise to ask everyone what the first circuit you made or replicated was? If you were me, starting from the beginning as you once did, what would you advise me to try to replicate in order to help me understand how everything works? I really want to get a handle on this because I feel like a blind man wandering in the dark feeling his way around at the moment.
     
  2. wayneh

    Expert

    Sep 9, 2010
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    There's no one answer but I'd wager that almost everyone here has built a variable voltage supply using the LM317, or a USB (5V) power supply using the 7805. They're a building block for many projects that follow.

    Using a photo sensor to trip a relay to act as a light detector is also on the list.

    The thing is, you should work on something that interests you. Just be sure to start VERY small, so that each step can be mastered. We see far too many noobies here trying to put a man on the moon, so to speak.
     
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  3. Rolland B. Heiss

    Thread Starter Member

    Feb 4, 2015
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    Thanks wayneh. You said just enough to spark my curiosity without giving me a particular schematic. I just hope I don't electrocute my self to death as I attempt certain things! One hand behind the back, right? ;)
     
  4. bance

    Member

    Aug 11, 2012
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    Try a transistor amplifier, and don't feel like a circuit that doesn't work is a failure. I hardly ever get a circuit to work first time....

    Steve.
     
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  5. Rolland B. Heiss

    Thread Starter Member

    Feb 4, 2015
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    Thanks Steve! Trial and error. I always loved the Edison response after he was asked by some reporter how it felt to try 100 times or so to make a battery and fail to do so. From memory his response was something like this: "What do you mean, failed? I now know 100 ways how not to make a battery!"
     
  6. MrChips

    Moderator

    Oct 2, 2009
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    Build a crystal radio with one of those germanium diodes.
     
  7. Rolland B. Heiss

    Thread Starter Member

    Feb 4, 2015
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    I plan on doing that. I did it once when I was a little kid but the kid was smarter than the adult. Or the adult was forced to become too distracted trying to make ends meet. Few of us have the luxury of being what we can when there are a bunch of other people in the political arena claiming to represent us who only seek that which they can steal with a smile claiming they represent our will.
     
  8. WBahn

    Moderator

    Mar 31, 2012
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    I don't know how well this works as an adult, but when I was a kid my uncle gave me the Radio Shack 65-in-1 Electronics Kit (which was the BIG one back then) and that was all she wrote.

    My first "real" electronic project was a code practice oscillator that I built in high school. Still have it, though I haven't played with it for many years so I don't know if the caps are still good.
     
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  9. sirch2

    Well-Known Member

    Jan 21, 2013
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    The first few projects I made which stick in my mind from nearly 40 years ago were a crystal radio, an inductance/capacitance bridge, a timer that used the discharge of a capacitor to switch a transistor and various transistor radio receivers. Then I got a Forrest M Mimms book of 7400 circuits and built a load of those.

    I guess these stick with me because they are the ones that taught me something and were successful
     
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  10. MrChips

    Moderator

    Oct 2, 2009
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    My experience coincides with that of WBahn:

    1. crystal radio set (which I still experiment with as of today)

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    2. electronics kit (Philips Electronic Engineer) which I wish I still had

    [​IMG]


    3. code practice oscillator (which I still have)

    [​IMG]
    multipurpose:
    1. test batteries
    2. test NPN and PNP transistors
    3. code practice
     
    Last edited: Mar 6, 2015
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  11. Sinus23

    Member

    Sep 7, 2013
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    Converted a speaker into a microphone. It was just a 1/4" jack away...;)
     
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  12. alfacliff

    Well-Known Member

    Dec 13, 2013
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    I built a signal tracer - audio amp with direct input and detector input, battery powered and a couple of tubes. the last test equipment I built wasw a spectrum analyzer, 1 to 1000 mhz.
     
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  13. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    Crystal radio, photo-electric relay (first science fair project), 2-tube AM receiver, 2-tube AM transmitter, shotgun microphone (second science fair project), game show controller. Then a 48-channel digital I/O interface for a PDP-8.

    I agree with others, the place to start these days is with a simple power supply. You'll need one or two for whatever you do next anyway (except for the crystal radio). There are many threads here and piles of schematics on the web.

    A few months after you've been using your power supplies you'll wish you had included some feature. That's the first step on the road from project design to product design.

    ak
     
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  14. takao21203

    Distinguished Member

    Apr 28, 2012
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    See photo on the left...
     
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  15. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    I repurposed a 1.5V light and battery, dissassembled it and remounted it on a wood board with thumbtacks as terminals. Since it had no ON/OFF switch I made one out an old house key and more thumb tacks. Worked nice in my tree house.

    May not seem like much but I was 7 years old and just made it up as I went along.

    Six years later I got some cool RTL chips (dual NOR gates and maybe a flip flop too) and diode steering board (decimal to binary converter) which kicked off several years of logic learning projects.
     
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  16. RURC

    New Member

    Mar 6, 2015
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    I can safely say I dont remember the first but I do remember buying a Commodore Pet home computer kit in 1980. My dad and I put it all together and bought a massive 32K memory expansion for it. I remember the memory expansion case was the size of a lunch box. What fun.
     
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  17. MaxHeadRoom

    Expert

    Jul 18, 2013
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    As mentioned in your post for 'free energy' Mine was a crystal radio also, (cats whisker type) as kids we had no money for batteries, fortunately it's not needed in this case.
    Max.
     
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  18. Hypatia's Protege

    Distinguished Member

    Mar 1, 2015
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    IIRC it was an 8080A based system from scratch --- Hey don't laugh! 8 bits was all the rage back in the 1980's and *no* it wasn't masochism!

    With nostalgic regards
    HP

    --Edit for typo--
     
    Last edited: Feb 5, 2016
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  19. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I made my first simple PLC from Motorola MC14500 1 BIT processor!
    Fun at the time!:confused:
    Max.
     
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  20. crutschow

    Expert

    Mar 14, 2008
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    Unless you are working directly off the mains (which you should never do) or with tube amps, there's not much chance of that.
    To power your circuits you can start with a cheap wall wort (plug in adapter) to generate a safe, low voltage. Make sure you pick one with a regulated DC output.
    5V and 12V are good voltages to start with.
     
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