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What was your first circuit? Do you still remember it?
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Kleinstein:
The first circuit I remember was in school, more or less try an error putting together 4.5 V batteries, lamps and switches. We somehow ended up in funny version that used 2 batteries, 2 lamps and a single, single simple switch in a way that either one or the other lamp was active.  It took me very long to find out how this could work and for this reason I still remember.

Probably this is still a nice puzzle for the beginners.
daveyk:
That's a long way to recollect.

I guess in school one of our teachers had us use magnet wire to wrap around a ~5 inch long 1x piece of wood to make the primary tuning coil. There was a point scrapper we made in metal shop class that would stand off the hunk of wood that we mounted the coil on. That scrapper was probably connected to the bottom (he'd) side of the coil. The scrapper was then scrapped across the coil in a wide arc and could tune the coil. The top of the coil went to a rectifier diode. We experimented with numerous ones, but I recollect using a corroded razer blade and another small piece of metal above it with a slice in it. From the slice was a dangling piece of magnet wire just touching the razor blade. Free m that slice metal, if I recollect correctly we hooked a crystal earphone from there to the ground (bottom of the coil). Between adjusting the razor blade rectifier and tuning to the coil you could tune in one of the two local AM radio stations.

That was too cool. From there that led to a curiosity of electronics, CB Radio, Ham Radio and a career in electronics.

I very fondly remember Radio Shacks P-Box kits. I can remember building a shortwave radio from one, building the RF preamplifier kit and a audio amplifier kit. I mounted all of that in a shell of a drawer storage unit with a piece of 1/8" paneling as a front panel with the controls sticking out. I listened to The His an Her show on it from Radio Nederlands broadcasting from the lesser Antilles (or something like that). I remember playing their Easter egg hunt (a world geography quiz) and mailing in my answers, getting a QSL card from them and hearing my name and results on the shortwave air!!! I was in heaven back then. I wish I could go back in time a re-experience that and teach myself to better appreciate the experience and better remember it and that in the long run, it is the best time of life growing up with a wild eye curiosity. That thirst for knowledge back then is better than having the answers.

Of course I tore apart old TVs back then and actually managed to fix a couple. Tore apart radios. Fixed a BC348Q(?) B17 shortwave receiver and using it for years.  Later built a bunch of Heathkit stuff, which I have sold all of it except for the 2m transceiver. Sigh, I sold my youth. All that is left is quickly fading memories.




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German_EE:
Back in the dim and distant past (yeah, I'm old) a magazine called Practical Wireless used to have a series called Take Twenty, simple circuits using less than twenty components. Well, I built a TRF radio from a Take Twenty design, I remember that it used a 2N2926G transistor and I built it by drawing the schematic on cardboard then pushing components through but that's about it.

Oh yeah, it didn't work first time, I learned fault finding at an early age.
Red Squirrel:

--- Quote from: bd139 on July 28, 2017, 10:47:02 am ---This was mine :)



--- End quote ---

I actually have one in storage that is similar.  I need to actually dust it off some day and go through it again for nostalgia sake, and now I'd actually understand the stuff it explains. Back when I was a kid I just put the wires where it told me and was like "cool!" but did not know how it actually worked.


 
bd139:
Yeah those kits certainly lacked explanation. This lead to the demise of mine when I decided to "work it out" blowing just about everything up in it  :palm:

Then I got the Forest Mimms book followed shortly after by The Art of Electronics (1st edition!) which actually made sense then.



--- Quote from: German_EE on July 28, 2017, 05:54:34 pm ---Back in the dim and distant past (yeah, I'm old) a magazine called Practical Wireless used to have a series called Take Twenty, simple circuits using less than twenty components. Well, I built a TRF radio from a Take Twenty design, I remember that it used a 2N2926G transistor and I built it by drawing the schematic on cardboard then pushing components through but that's about it.

Oh yeah, it didn't work first time, I learned fault finding at an early age.

--- End quote ---

I got a load of those from a car boot sale once in the 1980s. Great magazine of the time! You can actually download old issues of it here: http://www.americanradiohistory.com/Practical_Wireless_Magazine.htm

Hardly anything in PW worked properly. It usually had poor designs based on particular transistor beta and recycled reject parts by the original authors.
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