Nice video. I believe the 2N35 NPN transistor I had, was the HC-49 package
History from 1953 that looked forward.
Who in 1953 would have guessed that in 1959, a couple of Amateur radio operators pointed their beam antennas around the world, with the beam front back direction the Long Way, 13,000 miles.
The transmitter used 2 Philco Surface Barrier transistors. One was the oscillator, the other was the "power" amplifier. 100mW input, ~ 65mW output, at 11/10 Meter band. CW of course. The contact was solid.
Just a little factoid for those who have forgotten . . . a transistor can be useful at 1.2 x ft.
Just use the transistor in Common Base mode.
History from 1953 that looked forward.
Who in 1953 would have guessed that in 1959, a couple of Amateur radio operators pointed their beam antennas around the world, with the beam front back direction the Long Way, 13,000 miles.
The transmitter used 2 Philco Surface Barrier transistors. One was the oscillator, the other was the "power" amplifier. 100mW input, ~ 65mW output, at 11/10 Meter band. CW of course. The contact was solid.
Just a little factoid for those who have forgotten . . . a transistor can be useful at 1.2 x ft.
Just use the transistor in Common Base mode.
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"A device that does many things a vacuum tube does" is the Field Effect Transistor.
FETS & MOSFET's clip & distort with predominantly second order harmonics - just like tubes.
Also, they have a 'negative temperature coefficient' so they don't easily self-destruct, also like tubes.
FETS & MOSFET's clip & distort with predominantly second order harmonics - just like tubes.
Also, they have a 'negative temperature coefficient' so they don't easily self-destruct, also like tubes.
Oskar Heil, the inventor of the Heil Driver Tweeter, also invented the Junction Field Effect Transistor in the 1930s.
Unfortunately, there was no foundry that had the capability to actually build it was not possible then.
Bell Labs built the dual point contact bipolar transistor . . . low frequency capability, noisy, and needed to be used in the common base mode.
What happened after that, nobody could have guessed.
Did you know that in the US, the 8VSB digital TV transmitters use a modified form of the Klystrons from the 1930s.
What goes around, comes around (De Ja Vu all over again).
Unfortunately, there was no foundry that had the capability to actually build it was not possible then.
Bell Labs built the dual point contact bipolar transistor . . . low frequency capability, noisy, and needed to be used in the common base mode.
What happened after that, nobody could have guessed.
Did you know that in the US, the 8VSB digital TV transmitters use a modified form of the Klystrons from the 1930s.
What goes around, comes around (De Ja Vu all over again).
This is amazingly 'nostalgic' >
I still have a quantity of 'AS germanium' transistors. They even got them up to 1 amp plus.
Did you know that Germanium is now actually playing a part in Hi Tec ?
I still have a quantity of 'AS germanium' transistors. They even got them up to 1 amp plus.
Did you know that Germanium is now actually playing a part in Hi Tec ?
When I was 12 my Catholic school one-room library had a copy of "The Boys Book of Radio Electronics" by Alfred Morgan. The nun saw me checking that book out every week. It had experiments using the CK722 transistor along with the tube experiments:
https://en.wikipedia.org/wiki/CK722
That year dad gave me an Eico siren kit that used a 2N3055, I made a burglar alarm for the basement door.
https://en.wikipedia.org/wiki/2N3055
https://en.wikipedia.org/wiki/CK722
That year dad gave me an Eico siren kit that used a 2N3055, I made a burglar alarm for the basement door.
https://en.wikipedia.org/wiki/2N3055
I had a pair of CK722 transistors.
And, even better, I had a beautiful Project book from Raytheon, with lots of practical circuits using them.
Start reading and tinkering when you are young, and you will never stop (and you will be young no matter how old you get).
And, even better, I had a beautiful Project book from Raytheon, with lots of practical circuits using them.
Start reading and tinkering when you are young, and you will never stop (and you will be young no matter how old you get).
I first met the transistor at about age 9. My father got me one of those 50 in 1 electronics experimenters kits with the little spring connectors and a piece of pegboard. This was a high quality kit made by GE that featured 4 or 5 black 'top hat" germanium transistors. One of them was an NPN, quite rare in 1960 or 61. Some of us remember Poly-Paks (no time to test em) bagged transistors that may or may not work. Those that did not work met the wall outlet at the end of an extension cord. The plastic Raytheons (CK722 and others) made a big bang when they were subjected to such a "test." Over 60 years later I'm still "testing" stuff.
I remember getting one of those for Christmas, maybe 1967. Spent more time with my Meccano IIRC.
jeff
Back in the late 50's car radios used space charge vacuum tubes that ran with 12 volts on the plate. The "big" 12K5 tube could put out a whopping 35 milliwatts of audio power, so most radios used tubes for all but the audio output stage which used a fat TO-36 germanium transistor in class A SE working into a step up OPT. By the mid 60's these radios were being ripped out and replaced with something more modern like a Lear Jet 4 track player, or later on the popular 8 track deck. Old car radios could be found in junkyards and flea markets for free or cheap. I just kept the fat transistor and the OPT for my experiments. My "bench power supply" was an old Lionel train transformer, a big selenium bridge rectifier (later replaced with car alternator diodes) and a couple fat can electrolytic caps. Some science experiments used one to three 6 volt lantern batteries in series. Some of the fat germanium transistors could eat 3 batteries, but none could handle 4.
Well silicon-germanium has been a main-stay of microwave devices for many many decades, even some opamps are SiGe these days... And another use for germanium is lenses for thermal cameras, germanium detectors are used for gamma and X-ray spectroscopy, germanium doped optical fibres are used for various purposes in non-linear optics, and on and on....
Bill Lear invented the 8 track tape player originally as an element of the Lear Jet air plane. He later kept the rights to the patent after selling off Lear jet and went on to manufacture 8 track stereo car players. Muntz invented the 4 track stereo tape player. Mickeystan
I met my first transistor around age 9 too, but they were the silicon variety. Yep, one of those 100 in 1 electronics “kits”. But Ge devices were the bomb for making very simple audio amps, and every chance I could scavenge them I did. The old TO-1 types like 2SB54, 56. Lots of TO-3’s, and a few of the big doorknob types out of the car radios. And Radio Shack used to carry the 2SB407 which could make a nice push pull 10 watter in pairs. You just had to find a salvaged driver transformer. They would eat 24 volts. But not 36. Couldn’t expect miracles. I blew up a pair of 80 volt doorknob types on a 64 volt supply learning what second breakdown was. Sounded good but lasted about 5 seconds - blew up still stone cold.
I meant AC series.
I think my Electronics Experiments Kit was a 50 in 1. Such a wonderful & fun gift in the day - Cheers to many parents.
I remember my first introduction to a power transistor, the 2N301 - I was just fascinated by its capacity.
https://www.google.com/imgres?imgur...=OqTwpZV26kK0NM&w=1024&h=768&source=sh/x/im/1
My early circuits were mostly based on military surplus from the local MARS network, or old TVs from the side of the road. Military components were individually packaged in tan paper blister-packs. The packaging had to cost as much as or more than the individual passive components.
They still make those electronic experimenter kits. I got one of these for my grand-kids : Snap Circuits 300 in one
They still make those electronic experimenter kits. I got one of these for my grand-kids : Snap Circuits 300 in one
TheGimp: The guy that invented Snap Circuits was at Dayton Hamfest the past couple years, he's up there in years, his son had an indoor booth selling a similar new product that is more like electronic Lego Blocks. So kids still have options if you can get them off their tablets for a day at least!