Look at this!
An Op-Amp made with Transistors!
The XL741 Discrete Operational Amplifier | Evil Mad Scientist Laboratories
I heard they'll get smaller when we go to the moon.
Look at that! I built one!
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Look at that! I built one!
Sigh… this is what I get for whoring my silly electronics projects that I do in my spare time out for valueless likes on a bass guitar web forum.
You're too kind. Every inch under my bed is occupied by unfinished electronics projects. You actually get stuff done!
Yeah! Totally! That!That loopout was done intentionally. It's there for clipping on a scope probe.
That loopout was done intentionally. It's there for clipping on a scope probe.
Since you mentioned 'scopes, I feel I have to relay this story.
I built that opamp as soldering practice for my new job as Audio Visual Technical at the leading medical school where I work, or as I like to call it: MD PhD XLR. To help me do my job, I brought in my one of my two oscilloscopes, a DSO Nano v3. As it has been four weeks since I was tasked to create and verify the death certificate on a Crown Macrotech, said tiny oscilloscope was had vanished into the pile of papers, cables, Class-D modules salvaged from internal PC speakers, splitters, components extracted from a Crown Macrotech, and cables I recently conceited ownership of my deskspace to.
Needless to say, that my 'scope had gone missing had proved a major speedbump in my proof of concept proof-of-ability-to-solder-and-fix-stuff, um, experiment, so, as I so enjoy doing, I uttered a sentence that I am pretty sure has never been said.
"Damnit! Now where did I put my oscilloscope!"
That 741 is a beaut!
Many many hand built "professional" circuits have a component of two that looks a little lopsided. It's fine as long as the pins point the right way. The professional assembly was more about speed, and still try to keep some accuracy.
Now build a stomp box with a window for it!
Here's a great section out of a Walter Jung book on op amp history. Jung's books are King!
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It goes from tubes to transistors up ICs and fet ICs
Early solid-state op-amps were just like this 741 beast, but not so big usually.
It's interesting. Op-amps don't really care what device they have to work, but depending on the device they can work better for an application.
The early IC's were hand soldered from the chip pads to the legs. Fine little wires hand soldered under microscopes by careful but fast hands. Now what needs to happen is vintage IC market where the hand soldered ones are the hot commodity
Many many hand built "professional" circuits have a component of two that looks a little lopsided. It's fine as long as the pins point the right way. The professional assembly was more about speed, and still try to keep some accuracy.
Now build a stomp box with a window for it!
Here's a great section out of a Walter Jung book on op amp history. Jung's books are King!
Invalid Link Removed
It goes from tubes to transistors up ICs and fet ICs
Early solid-state op-amps were just like this 741 beast, but not so big usually.
It's interesting. Op-amps don't really care what device they have to work, but depending on the device they can work better for an application.
The early IC's were hand soldered from the chip pads to the legs. Fine little wires hand soldered under microscopes by careful but fast hands. Now what needs to happen is vintage IC market where the hand soldered ones are the hot commodity
Here is one example, the Philbrick op amp drives the MOSFET output stage. The offset is held to near zero using a modern op amp as a servo (Jung "Op Amp Cookbook")
