) writes:
I own a Heathkit IP-17 which had identical rating to the HP-23 that you
have. For higher amounts of current, I cobbled together the combination
of a Variac, a salvaged TV set power transformer, bridge rectifier, and
filter capacitors to do the job.

Although unregulated, it performed its job well for many years.

There have been a few threads recently about regulated tube supplies,
and each time I see them, I keep wanting to post "but most supplies in
the days of tubes were not regulated".

It's almost as if people have lost that fact, so used to solid state
where regulation is the norm, though regulation there often means
a different thing. Now it's used to get a low impedance out of the power
supply, or because the devices are finicky over a wide range of voltages (or
outright can be damaged by too much voltage, as in the case of ttl). Of
course, three terminal regulators made it easy to add regulation to
just about any sold state design decades ago.

But of course, for most consumer equipment there were no regulators (though
that may mean little since there was little consumer electronics around
the house up till about forty years ago) If there was regulation it
was a VR tube, and for a specific stage or stages, liked an oscillator
stage that would change frequency with voltage variation, rather than making
the whole supply regulated.

It was in the lab that most regulated supplies were seen. All that
test equipment is a prime example. You wanted reproduceability for
that DC coupled scope, so you'd want it well regulated.

I guess in the lab you'd see variable voltage regulated supplies but
that would have been the key place.

Michael VE2BVW