Memories of electronics..

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The oscilloscopes are always fascinated me.
I have three oscilloscopes.
So what?
My wife has three, not three, but four sewing machines!
These are much noisier.
And she got from me two sewing machines.
Do not ask, how many oscilloscopes I got from her.

This reads like free-form poetry. Once again, I have to say I enjoy reading the things you write more than anything else on this forum.
 
When I think back to the early 70's and my early forays into burning components I hide my memories in shame.

In those days it was almost impossible for a young teenager to learn about electronics, that was a World reserved for university graduates.

I can remember someone telling me that you could drop voltage across a resistor. Needless to say I used my non-existent knowledge to build a transformerless PSU.

How I never burnt my parents house down or killed the cleaner (Mum) I don't know.

I've got a degree in Electronics these days. That doesn't make me an audio expert though.
 
In those days it was almost impossible for a young teenager to learn about electronics, that was a World reserved for university graduates.
I'm puzzled. I would have thought that in those days it was a lot easier to learn about electronics than today. That is when I learnt about electronics. School maths and science were at a higher standard than today, so the prerequisites for electronics were in place.
 
I too am nonplussed. The electronics magazines I devoured almost every month in the early and mid 70s probably have few parallels today - Everyday Electronics, Practical Wireless, Practical Electronics, ETI, Wireless World, Elektor.

I was introduced to electronics at school by a teacher who kept a kit in the classroom. Every Wednesday afternoon we were given the choice of which 'toy' to play with, I mainly gravitated towards building a crystal radio. I recall spending considerable time trying to get my head around how 3 legged transistors (black painted glass, so perhaps OC71s) decided how to divide up the current between those 3 wires. In comparison, diodes and resistors were pretty straightforward. This would've been around age 10 or 11.

<edit> The very same teacher also introduced us to his induction coil, which was wired to a pair of spoons. He'd have the whole class hold hands (probably around 35 kids) in a big circle and fire it up. We dropped hands pretty quick! Nowadays I guess such antics would be illegal. One of the boys in the class proved how 'hard' he was by holding the two spoons by himself and refusing to let go...
 
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I remember early days,

Building my first power supply with a 5W Zenner to get the supply rail..I thought "why no voltage" ???...so touched the metal cased zener as my skin stuck to it and blistered across my thumb and finger about half an inch..

After putting my hand under the cold water tap to cool it and dancing on the spot for about 5 minutes..Looked at the now burned vero board to find it was connected backwards..This was followed by playing with neons to create a relaxation oscillator (just for fun could I run disco lamps from them), Then putting them back in the mains lamp for the PSU...switch on and BANG a small rocket flew past my face...Forgot the resistor..

The next step was looking at the turntables in the local electronics shop..I wanted a Goldring OK well I'll have a Garrard but could only afford a BSR.....What cartridge MM/MC er well MM is easier to do...So BC109 preamps and trials with LM381 for possible MC upgrade.. and whats RIAA?? Back to the Horrible books...Then build it all into the plinth with TIP41a power amp..and HUMMMMMMMMMMMMMMMMMMM.....tried everything...then oups the mains motor from the deck is not running on top of the plinth when testing it..:mad::mad:

How to screen the top from the bottom section took days to figure it out....and wooohooo..er the volume control works backwards...then why do I need a log pot...and dreaded tone controls " Baxandall"

Such happy times with the 45s and albums....a bunch of kids doing what is necessary with pocket money..

Regards
M. Gregg
 
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Joined 2010
I too am nonplussed. The electronics magazines I devoured almost every month in the early and mid 70s probably have few parallels today - Everyday Electronics, Practical Wireless, Practical Electronics, ETI, Wireless World, Elektor.

I was introduced to electronics at school by a teacher who kept a kit in the classroom. Every Wednesday afternoon we were given the choice of which 'toy' to play with, I mainly gravitated towards building a crystal radio. I recall spending considerable time trying to get my head around how 3 legged transistors (black painted glass, so perhaps OC71s) decided how to divide up the current between those 3 wires. In comparison, diodes and resistors were pretty straightforward. This would've been around age 10 or 11.

Yes, I remember the cross section of books and the drive to build your own...
Looking in the magazine shops now its a bit thin on the ground... Ahh yes the Van de Graaff generator....also spawned a pop group..Yes the local Physics teacher who let me borrow a variable power resistor and a few bits and pieces..also access to a scope....

Regards
M. Gregg
 
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I must add,

I went to see my friend who went to work for the BBC, At his house...He had built a microphone preamp that was very sensitive...(He lived next to the local park)
He said watch this there are some girls I know over their..I looked I could just see them...He got a glass bowl off the table and said turn the amp up..he moved the mic in front of the bowl with the window open..Then the sound of birds and cars going by and :eek: Talking...what....yes the girls we could hear everything they were saying...so you can see why he was destined for the BBC...we were only 15..:D

Regards
M. Gregg
 
Yes, I remember the cross section of books and the drive to build your own...
Looking in the magazine shops now its a bit thin on the ground... Ahh yes the Van de Graaff generator....

I remember the Van der Graaf generator in the lab, and Leyden jars, made of glass vessels and aluminum foil.
It was cold, and go unnoticed, the thick gloves of a fellow.
He charged the Leyden jars, and threw them to us, then understood what his gloves.:wave2s:
Curiously no one dropped to the floor.:confused:
Another fellow had a very pointed nose, got too close to the generator...edge effect.:D
 
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I remember the Van der Graaf generator in the lab, and Leyden jars, made of glass vessels and aluminum foil.
It was cold, and go unnoticed, the thick gloves of a fellow.
He charged the Leyden jars, and threw them to us, then understood what his gloves.:wave2s:
Curiously no one dropped to the floor.:confused:
Another fellow had a very pointed nose, got too close to the generator...edge effect.:D

LOL..
Spark erosion
The new cosmetic nose treatment..:D

I remember in the first year of college one guy stayed out late at night all the while so was always falling to sleep in the lessons...He jumped up on the bench and dozed off as the lecturer was talking ...OWWWWWWWWWWWWWWWWW he shot off the bench..sat on a soldering iron and the lecturer had reset the safety..it burned right through his trousers before he woke up...

Regards
M. Gregg
 
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I'm puzzled. I would have thought that in those days it was a lot easier to learn about electronics than today. That is when I learnt about electronics. School maths and science were at a higher standard than today, so the prerequisites for electronics were in place.

Right. Also I did not have parts to build something, so I was spending evenings is a public library reading Radio magazines, from 30'th to 60'th ears. Reading and drooling, dreaming to have all that parts. :D

Then I bought a vacuum tube reference book and a book of schematics of transistor receivers. They were my main books for several years, until I graduated the school.

But when I graduated the school I already knew how to fix radios, TVs, tape recorders. I have built transistor amp for bass guitar and tube amp for lead guitar (with Gu-50 outputs, by the way), and many guitar effects.
 
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The next build,

Talking to people, discussion went like this," I think I would go all cassette tape because they are easier to store than LP's".

So I looked around and bought a Monolith Magnetics cassette transport...This became a challenge with NAB tape EQ and the pre section was a real pain to get working without hum...don't know why but I thought it would just be as simple as RIAA pre amp topology..Was I wrong..:)

I managed to get a Dolby module that was available at the time from Maplin..Built a discreet component dual bar graph for the output power (no chips)In Practical wireless at the time, Bass & treble controls and again LM381a pre section built on an RS PCB...Polycarbonate coupling caps...Help from electronic engineers I worked with at the time..:)

Toroid power and separate Regulators for the PSU dual reg for the NAB pre section to get the noise down..Circuit board made for TIP41a<<my favorite at the time..power section 25W per channel..I was 18..Aux Input soon put in to connect the record deck that I could not live without...:D

I do cringe now when I think about all the tubes that became bombs out of the bedroom window when I was 9..LOL...

Regards
M. Gregg
 
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What happened to the good old days?

Pull out freebies:

Regards
M. Gregg
 

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