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- Why do we have to hand wind toroids? 2 answers
In most schematics of ham radio receivers and transmitters the inductor is mostly given specifically as the number of turns around some certain toroidal ferrite ring (for example). This corresponds to a certain inductance, which more often than not is just a standard value, say 220uH. These exist also as "lumped element" components, like the ones in the picture:
It seems a precise inductance is quite difficult to achieve (with homemade coils) and measure, whereas with store-bought inductors this problem is largely gone.
Why are hand-wound inductors so common?
Is it just a nostalgia thing? Do they tolerate more power? Why don't we need to do this with capacitors as well?