Tony Duell wrote:
I nthe 1920's, Lowe (in Germany) made a radio
receiver which consisted of
a tuend ciruit, headphones, batteries, and a single glass envelope. That
contained 3 triodes and all the R's and C's.
I posted a link to that earlier. I think at that time Germany had a
(a) I read your message after I posted the above. (b) I read my mail
off-line, and I am not going to dial in to check every URL that people
post... (As a general point, I wish people would make some comment when
they give URLs -- of the form 'Lowe one-tube radio' or whatever.
large tax on radios,
more tubes, bigger the tax.
I've heard that such taxes lead to the introduction of multi-section
valves (double triodes, double diode pentodes, triode hexodes, etc). But
there was no need to put the R's and C's in the envelope too, and AFAIK
the 'vacuum integated circuit' (:-)) was signfiicantly more expensive
than the valves alone. The R's and C's were a significant cost.
-tony