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I bet that works good

Posted by Tre' on February 17, 2025 at 13:34:15:
The Bartola is taking the output from the mu output connection on the lower device of the CCS plate load. That works like a cathode follower and should have a pretty low output impedance all by itself.
One thing I don't understand about his design, He has a bias voltage coming through P1. He could turn that up which would force him to increase the value of R4 to keep the same set current. That would be a good thing. R4 is not only the current set resistor but it is also acting as the "cathode" resistor if viewing the lower device (M2) as a cathode follower. The larger the value that resistor is, the more feedback there is for the device and that would lower the output impedance of the mu output.
The other thing I don't understand is this, "All schematics and designs are copyright Alejandro Moglia and Bartola Ltd. UK unless stated otherwise. All rights reserved. You are welcome to build the circuits presented here for your own personal entertainment. You may NOT build from information on this page for commercial profit without a royalty agreement with the author in place."
All a copyright prevents others from doing is coping the image of his schematic. Like making a copy of a copyrighted book and selling it. A copyright does not protect ideas. A circuit design is an idea. To protect a circuit design he would have to patent it. To patent it it would have to be new and unique. I'm not sure he's done anything that hasn't been done before.
Oh well, there are a lot of things I don't understand in this world.
Tre'