Electronics history

[gui_tarzan]

I was explaining how I went about troubleshooting a recent repair to the new guy in the shop that farms out some of their tube work to me yesterday and it brought up something I've wondered about in the past. If you think about the component level, and even deeper into the theory of operation of electronics, there are some very magical things that happen. To some they may not be "magical", but to those of us that are young enough to have missed the early days of electronics, it certainly is.

For example, what made someone think by wrapping paper and foil into a cylinder that it would not only filter certain frequencies, but also block DC yet let AC through in certain situations? Seriously, who would have made that connection? How about knowing that electrons, something you can't see with the naked eye, would flow from a negatively-based point to a positive-based point? And then you could use a grid to control that flow? You can't see them without an electron microscope and you can't measure them without a meter, so where did the idea for a meter come from?

And don't get me started on how AC and DC can flow down the same wire.

Just some thoughts to make the synapses fire a little more.

[Leo_Gnardo]

Mostly you have the guys who units are now named after, Faraday, Ohm, Ampere, Volta, Henry, Oersted etc. And the guy who tied it all together with four neat equations Jimmy Maxwell. And one early experimenter whose name may be lost to history, when he caught a whopping shock from a Leyden-jar capacitor wrote "I thought it was all up with me." OW! He may have had a few choice words to say before he wrote that down, best left to the imagination.

[nickb]

I was explaining how I went about troubleshooting a recent repair to the new guy in the shop that farms out some of their tube work to me yesterday and it brought up something I've wondered about in the past. If you think about the component level, and even deeper into the theory of operation of electronics, there are some very magical things that happen. To some they may not be "magical", but to those of us that are young enough to have missed the early days of electronics, it certainly is.

For example, what made someone think by wrapping paper and foil into a cylinder that it would not only filter certain frequencies, but also block DC yet let AC through in certain situations? Seriously, who would have made that connection? How about knowing that electrons, something you can't see with the naked eye, would flow from a negatively-based point to a positive-based point? And then you could use a grid to control that flow? You can't see them without an electron microscope and you can't measure them without a meter, so where did the idea for a meter come from?

And don't get me started on how AC and DC can flow down the same wire.

Just some thoughts to make the synapses fire a little more.

Thank heaven capacitors are not called "Musschenbroeks". See here

What me hooked was all that action at a distance stuff i.e. the strangeness of magnetism, radio waves, electrons pummelling through a vacuum...

[olddawg]

Tesla!

[Leo_Gnardo]

Tesla!

Tesla sure & Gauss too. What would we do without Fourier the mathematician who figured out his methods by studying the way heat travels through sheet metal. Who could expect he'd figure out anything from that? Via Fourier all waveforms are described by a collection of sine waves, pure genius!

[Jazz P Bass]

As the OP has started a nice thread, I took the initial post as being vague.

The history of "electronics" is filled with glowing characters.
But you have to keep in mind that the whole field is a string of discoveries.

The Greeks new about static charge.

Discoveries languished all through the Middle Ages ( thankyou, Religion)
Then it picked up again in the 1500's with magnetism & a new interest in static charges.
The 1700-1800 saw some brilliant minds researching the very basics.
In the 1900's, the very nature of the atom was exposed.

We are all, truly standing on the shoulders of giants.

[olddawg]

And then there was DeForest who bumbled his way through everything but made a massive contribution.

[Enzo]

Yes, it was all incremental. They started with two parallel conductors. Electrolytes and rolled up came later. Leyden jars came along as some of the first capacitors over 250 years ago. A capacitor will store a charge, they knew that. All the later developments in caps and their uses came a step at a time over years.

You can't see electrons even WITH an electron microscope. That tool is so named because it uses electrons, not because it can see them. You cannot see electrons by any means, you can only see indications of them. The vacuum tube started as a diode. current boiled off one element and was attracted to a positive element. That established current. They knew positive attracted electron current and negative repelled it. Then someone tried putting something in between plate and cathode to see if it could repel electrons, preventing them reaching the plate. The grid was born.

Where did the idea of a meter come from? If you ever took a electronics introductory course, they started with light bulbs and magnets. They discovered that current through a conductor created a magnetic field. How did they know? A compass held next to the wire was deflected when current flowed. And they quickly found that reversing the battery made the compass deflect the other direction.The more the current, the more it was deflected. Right there is the first rudimentary meter. Every intro demonstration shows the class that.

AC and DC in the same wire is simpler than you might think. For example, you have 200vDC on the plate of a tube, and 100vAC of signal. The secret is that it is all DC. Alternating current means flowing one way, then the other. AC on DC just means the DC current is varying with a signal. SO the plate of that triode in the preamp is always DC, it just varies from say 150 to 250vDC with the signal. So we say we are measuring the "AC component" of the voltage at that plate, but that is not really correct, it is all DC.

[Leo_Gnardo]

The history of "electronics" is filled with glowing characters.

"Glowing characters", interesting choice of words. One could have been Ben Franklin. Some others who tried flying kites in thunderstorms literally got to be glowing characters I reckon...

Ancient Egyptians figured out how to do some electroplating.

Middle ages, file science under "Alchemy." Secret stuff, devil must be involved. Some still carry on as if that was the case.

Got to re-enact the Milliken oil-drop experiment in college physics lab, establishing charge of the electron and furthermore that it occurs in quantum amounts. Too bad for Ben Franklin & others who guessed the charge carrier was positive. It's all relative anyway :P.

Good mention Enzo of AC + DC. It was hard getting the principle of "superposition" thru some college kids' heads.

Gotta go look at the moon now, the universe is putting on a show. Already half in shadow and the rest going fast. Recommended for everyone & the price is right. Catch up with yez all later.

[Merlinb]

One could have been Ben Franklin.

It showed fantastic foresight on Franklin's part (or a very lucky happenstance) that he chose to call the two states of electricity 'positive' and 'negative' (or plus and minus). These words instantly sowed the seed for an explanation of electricity based on mathematics, at a time when natural philosophers didn't normally use mathematics to explain things. Ultimately it was mathematics that solved the abstract mystery of electricity. But if he has instead used the words 'hot' and 'cold' or something, it would have made the future mathematics a lot harder to follow, linguistically, and I suspect it would have taken longer for anyone to attemp mathematical descriptions of electrical behaviour, too.

You can read some of Franklin's "Experiments and Observations on Electricity (1769)" here -they are fascinating!
https://books.google.co.uk/books?id=...page&q&f=false
p13: "At the same time as the wire and top of the bottle is electrified positively or plus, the bottom of the bottle is electrified negatively or minus, in exact proportion: i.e. whatever quantity of electrical fire is thrown in at the top, an equal quantity goes out of the bottom."

The bottle, of course, was what we would now recognise as a capacitor.

Note to novices: If you read the book, remember that in Franklin's time an insulator was called an 'electric'. That is why the insulator separating the plates of a capacitor is called the 'dielectric' (dia is Greek for 'through', and current appears to pass 'through' the 'electric' or insulator).

[fdesalvo]

It showed fantastic foresight on Franklin's part (or a very lucky happenstance) that he chose to call the two states of electricity 'positive' and 'negative' (or plus and minus). These words instantly sowed the seed for an explanation of electricity based on mathematics, at a time when natural philosophers didn't normally use mathematics to explain things. Ultimately it was mathematics that solved the abstract mystery of electricity. But if he has instead used the words 'hot' and 'cold' or something, it would have made the future mathematics a lot harder to follow, linguistically, and I suspect it would have taken longer for anyone to attemp mathematical descriptions of electrical behaviour, too.

You can read some of Franklin's "Experiments and Observations on Electricity (1769)" here -they are fascinating!
https://books.google.co.uk/books?id=...page&q&f=false
p13: "At the same time as the wire and top of the bottle is electrified positively or plus, the bottom of the bottle is electrified negatively or minus, in exact proportion: i.e. whatever quantity of electrical fire is thrown in at the top, an equal quantity goes out of the bottom."

The bottle, of course, was what we would now recognise as a capacitor.

Note to novices: If you read the book, remember that in Franklin's time an insulator was called an 'electric'. That is why the insulator separating the plates of a capacitor is called the 'dielectric' (dia is Greek for 'through', and current appears to pass 'through' the 'electric' or insulator).

AWESOME post, OP - I've been in this mood since discovering this site: Technical books online

So fired up over the electron right now and this Franklin reference is going to be consumed this eve. This was truly the Romantic period. Modern electronics just don't appeal to me. Show me a mercury vapor tube and my imagination is ignited.

[gui_tarzan]

Great discussions guys! Can you imagine the joy experienced by the first person to notice that different gases turn those electrons different colors? Man, what an exciting time that must have been.

[überfuzz]

... Jimmy Maxwell.

James Clerk is twisting and turning in his grave. Heretic!!!

Actually Maxwell was the first who described controlled systems, by using mathematics. Well, some of you might have heard about transfer functions...

[Leo_Gnardo]

Great discussions guys! Can you imagine the joy experienced by the first person to notice that different gases turn those electrons different colors? Man, what an exciting time that must have been.

I dunno if he was first but Crookes was an early experimenter along those lines late 1800's. Imagine what he was thinking. "Wow cool man! Now I can make a Budweiser sign."

[Leo_Gnardo]

James Clerk is twisting and turning in his grave. Heretic!!!

Actually Maxwell was the first who described controlled systems, by using mathematics. Well, some of you might have heard about transfer functions...

Wha? "Daftie", he must have been as good at delivering as well as receiving a good Scottish sendup, undermining the excessive formality of academia. Amongst other things "brickbats" orbiting Saturn. But he sure was a wiz at understanding lots of things and putting them into equation format, what a gift. The four truths of electromagnetism were the Grand Unified Theory of the time, even Einstein was impressed. What would we do without him? I have a hard enough time explaining transfer functions to my crustomers, gotta use up a lot of chalk.