On Fri, 4 Dec 2015, gareth wrote:

I wonder what the extent of home manufacturing of componenets
is these days, apart from, say, microphones, earphones and Morse keys?

I think it's generally limited to curiosity, and the rare necessity.

I once helped someone make a microphone out of a razor blade and carbon
rods for a science project. It's not practical for home use, and even if
it wasn't a carbon microphone, it's just easier getting a commercial
microphone.

There was a period when the American hobby electronic magazines would show
how to make paper capacitors and "book" variable capacitors and such, but
they were presented as "here is how things used to be" rather than parts
for your latest project.

As mentioned, high voltage variable capacitors may be hard enough to get
that some may build there own, and there have been projects.

This sort of thing I suppose also works if you are trying to create
something special. Which is probably why code keys are often something
people build, the can create something as good or better as the commercial
products, and put some "art" into it.

But amateur radio is a wide hobby, endless sub-hobbies, so I'm sure there
are some making their own parts. Look at model railroad magazines (which
for some reason still seem to be healthy), that's often about making
little things.

Michael