4 Feb
2011
4 Feb
'11
11:34 a.m.
and TVs weew
'AC/DC',not just to save the cost of the mains transformer.
I rememebr working on TVs (long after the 1950s, of coruse) with
different voltage selector settings for AC and DC mains (possibly due to
fact that the smoothing capacitor would charge to the peak and not the
RMS votlage of AC mains). One of the Mullard books of audio amplfiier
cirucits (including things like the 5-10 and 5-20) includes a circuit
for an amplifier (4 valves, something like UF86, 2 * UCL82, UY85) for
AC/DC mains. Of coruse it was hot-chassis which is a right pain...
Hmm, I shall have to have a look at my Mullard book. I seem to remember
that one.