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smallmerc.jpg (1433 bytes)smallneon.jpg (1451 bytes)Lamps

Arc tubes   Flash lamps

lamp1.jpg (3937 bytes)lamp3.jpg (5366 bytes)< Mazda 24V 36W, with very odd base, believed to be for morse signalling lamp. Bulb 1 dia.

> Osram 12V 350W, military, probably for small searchlight or signal lamp. bulb 2" dia.

lamp2.jpg (5926 bytes)lamp6.jpg (5074 bytes)< Philips 340  lamp, 2" dia. x 4" long
Info from Ron Pond : The Philips type 340 is a current regulator tube that was used in one of their early battery chargers. ( I think there may even have been two of these in the one charger.)
They were designed to operate from between 3- 10 Volts at a current of 5.9 Amps, and had an Edison Screw type base designated type as a G2 base. Incidentally, the filament was made of pure iron immersed in an atmosphere of hydrogen gas. These tubes understandably got quite hot in operation and adequate ventilation was essential.

>Siemens 80V 1500W signalling lamp, 3" dia. x  8" long. See what happens when you put this bulb on a Tesla coil!

lamp4.jpg (2750 bytes)lamp5.jpg (5602 bytes)< Early top-sealed coloured lamp.  Info from Ian Shorrocks : You will note that the colouring on the outside of the bulb is quite thick and would attenuate the light quite considerably. In fact, I think you find will that your lamp is rated at (I'm trying to remember here, so I may not get this quite right) a couple of hundred watts or so from a 200 volt supply. Looking around the Science Museum in the domestic appliances gallery will reveal four more of these 'lamps' mounted in front of a polished reflector in an electric heater. These 'lamps' are in fact the electric heating elements for a very early electric room heater. The lamps were clearly intended to emit a comforting orange glow as well as heat.

> Philips 240V 100W projector lamp - note bulge in side, presumably due to insufficient air cooling.

Below - small early Mazda top-sealed 12V automotive lamp

lamp8.jpg (2279 bytes)

lamp9.jpg (6322 bytes)lamp10.jpg (5389 bytes)< Early Siemens top-sealed lamp, non-coiled tantalum filament.

> Cosmos 110V 200W early top-sealed lamp


lamp7.jpg (4798 bytes)< Royal Ediswan 'Pointolite' lamp. Marked 100 c.p. (candlepower), 100-240V.
Thanks to James Hooker for the following info :
They can be thought of as an incandescent arc lamp, and are used for projection work. Yours looks like it was made at the Ponders End, London factory around 1950, but we carried on making them afterwards at Leicester up to around 1970. This is how they work: First you apply about 7V through the filament which heats up. You will notice that there is a grey ceramic tube, called the ioniser, slipped over part of the filament tail. This is made of thorium oxide and is a great electron emitter and the filament heats this up. Then 100-240V is applied via a resistor across the filament and the tungsten bead, and an arc forms. The arc soon moves over to the ceramic rod as this becomes conducting when it gets hot, and takes the load away from the fine filament wire which would otherwise melt. The heat of the DC arc makes the tunsgten bead glow white hot, and forms a highly efficient point source of light, almost no light is produced by the nitrogen/argon discharge. I can't tell from your photo but yours may be of the type which has the bead mounted on a bimetal strip, this makes sure the bead moves away from the coil and next to the ioniser to prevent the filament getting too hot from the arc.
Here is some data on these lamps : Seimens-Ediswan    Mazda

bulb4.jpg (3779 bytes)> Experimental lamp with side tube, presumably to allow gas filling etc.? 

Info from James Hooker : This is probably a Pirani Gauge, used for measuring vacuum quality. The side tube is sealed onto a vacuum system, pumped down, and a low current applied to the filament to raise it to a couple of hundred degrees. Depending on how much gas is left in the system, the filament temperature will vary due to thermal convection losses in the gas. by measuring the filament resistance, you can calibrate a meter in units of vacuum pressure, making a very effective vacuum gauge.

lamp11.jpg (4190 bytes) 'Tricity Sunray Radiator' heat lamp, 10" long

lamp13.jpg (5828 bytes)Siemens 1000W 230V linear lamp, marked 'Property of H.M.Government' 12" long.

Flash lamps

flash1.jpg (3982 bytes)flash2.jpg (4577 bytes)flash3.jpg (5862 bytes)<Unknown flash tube, Mullard LSD3

> Philips Photoflux PF100E magnesium wire filled flashbulb.

Below: small (B9A base) EG&G FX102

flash5a.jpg (2854 bytes)

00A15003.JPG (272449 bytes)Hewlett-Packard flash x-ray tube. X-Rays emerge through a thin metal disk in the base (left).

Arc tubes

arclamp1.jpg (5531 bytes)arclamp2.jpg (9822 bytes)< Mazda 250W mercury-vapour arc tube (2" dia)

> Unknown arc tube (left) and Manufacturers Supply Co. HF3 Hydrogen arc lamp.
Thanks to James Hooker for the following info on the left-hand tube :-
this is a deuterium lamp, similar to the hydrogen lamp next to it but
is contains deuterium gas instead. We still make these today, they
get used in infrared spectrometers.

01208002.JPG (320170 bytes)01208003.JPG (335992 bytes)wpe11.jpg (15402 bytes)<Ultra Violet Arc lamp (marked D809 Germany), from a spectrometer. Probably a deuterium lamp (about 3 inches long). The tube was sealed into a metal tube and clamped to a heatsink. One reason for the sealing is probably to reduce ozone, which can be smelt strongly after the tube is run for just a few seconds.

> a pair of 100 watt short-path arc lamps, used in UV recorders (chart recorders which used moving-mirror galvanometers to record on light sensitive paper). The right-hand one has a third starting electrode to initiate the arc.

wpeB.jpg (61172 bytes)wpeC.jpg (58000 bytes) A couple of hollow-cathode lamps. These are used to produce precise wavelengths for spectroscopic applications. These produce narrow emission from various metals. They have a cylindrical cathode, made from the element of interest. The discharge ionizes rare gas (typically neon) atoms, which are accelerated into the cathode and sputter metal atoms into gas. Collisions with gas atoms or electrons excite the metal atoms to higher energy levels, which decay to lower levels by emitting light.

smallmerc.jpg (1433 bytes)smallneon.jpg (1451 bytes)

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