On 12 Jul 2007 at 19:53, Tony Duell wrote:
]1] Called 'Photoflash' or 'Hearing
Aid' batteries in the old books. The
fomrer because they were used to charage a capacitor of About 100uF to
fire the old single-shot flash bulbs.
Now, I thought that the "photoflash" appellation was due to their
being used in early photo strobe flashes. I can still remember
lugging around a Honeywell Strobonar that used a pack holding two
rather large 225v batteries--attached to the strobe head attached to
my Rolliflex. Recycling time was very fast--most sports
photographers wouldn't have been without them. There were also 510
volt batteries for more compact flashes.
Tying this into glow tubes, I recall a slave unit that used a
phototube and a cold-cathode "trigger tube", which must be the first
cousin to a Krytron.
It seems to me that there was an NE-something wire-lead bulb with 3
electrodes. Anyone have a reference manual at hand?
On a very tangential topic, I note that the illuminated wall switches
and dimmers in my house are slowly giving up their neon ghosts. Is
there a commodity LED part that can run from the 120v mains? The LED
"night lights" all seem to use a resistor a couple of capacitors and
a couple of diodes to drive an LED. Too much to squeeze into a
standard outlet box along with the switch.
Cheers,
Chuck