I was there then but do not remember. What was the first LED which we could buy?
Me, I was cheap, I waited for the price to fall to 10 for a dollar. Late 1970s.
I had heard tales of RCA asking hundreds of bucks each in the 1960s.
Here is a 1970 Electronics Illustrated article using one LED which you can buy at four and a half dollars.
For reference, a tightly selected neon lamp was $0.55 then. See my paste-in.
$4.50 was a full fill-up for a 1967 Mustang. The gas gauge had four quarters. One dollar bought almost one quarter tank. If you had really run it dry (girlfriend in another state) it would be a little more. So $4.50 then is almost exactly like $60 today.
Me, I was cheap, I waited for the price to fall to 10 for a dollar. Late 1970s.
I had heard tales of RCA asking hundreds of bucks each in the 1960s.
Here is a 1970 Electronics Illustrated article using one LED which you can buy at four and a half dollars.
For reference, a tightly selected neon lamp was $0.55 then. See my paste-in.
$4.50 was a full fill-up for a 1967 Mustang. The gas gauge had four quarters. One dollar bought almost one quarter tank. If you had really run it dry (girlfriend in another state) it would be a little more. So $4.50 then is almost exactly like $60 today.
Well, I think today you can fill up your Mustang reservoir with LEDs instead of gasoline and still won't exceed the gas bill.
Best regards!
Best regards!
The first commercial LED was the GaAs infrared type SNX-100 launched on the market in october 1962 by TI. It sold at $130 per unit. There is a nice paper about this device, written in 2015 by Thomas M. Okon and James R. Biard.
I also remember when blue LEDs made their debut on the DIY scene. They were
$10 each and very very delicate. When they came down to $4 I was thrilled and used them as power indicators on my home brewed stuff. I had red, yellow, green, and blue LEDs and thought it was the best of times in which to live! Now I have pink, purple, white, orange, aqua, and more! Oh how far we have come from the Stone Age of just red!
$10 each and very very delicate. When they came down to $4 I was thrilled and used them as power indicators on my home brewed stuff. I had red, yellow, green, and blue LEDs and thought it was the best of times in which to live! Now I have pink, purple, white, orange, aqua, and more! Oh how far we have come from the Stone Age of just red!
I imported a blue LED from the UK 35+ years ago. Its still glowing. Also remember reading a white paper on why it would be impossible to fabricate a white LED, let alone one that can blind you from a KM away... 🙂
10K 1/2W resistor on 400V? 16W....
This one is more frugal (but it only works on AC):
https://www.diyaudio.com/community/...-stray-currents-harvester.335610/post-5736940
This one is more frugal (but it only works on AC):
https://www.diyaudio.com/community/...-stray-currents-harvester.335610/post-5736940