25 Feb
2010
25 Feb
'10
10:01 p.m.
On 25 Feb 2010 at 6:22, Tony Duell wrote:
Presumavly you wanted the line output valve
('sweep tube'?) from the
latter to use as the transmitter PA.
Oh, much more than that--the radio was the source of variable
capacitors, but the TV was the treasure trove. A huge power
transformer, rectifier (usually something like a 5U4), filter caps,
horizontal output tube(s) (Some early sets used push-pull 6BG6s;
later ones just ran the horizontal output tube to within an inch of
its life. Plus ?a change...). The exciter could be a 6SJ7, from the
video output stage.
TV power transformers were very generous with filament windings and
the high-voltage winding was usually something on the order of 450-0-
450, so a fullwave bridge could be used to furnish plate voltage for
something much larger than the run-of-the-mill novice rig. Indeed,
there were hams who rewound TV transformers for high-power final
supplies.
Life in the trash heap was good...
--Chuck