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GE Lighthouse Halogen - Quartzline Q1000T20BP |
Its design is very different from European lighthouse lamps. Those typically employed large area filaments intended to approximate the size of earlier oil burners, and ensure compatibility with the huge optical systems of the early lighthouses. This American lamp instead employs a compact coiled-coil axial filament, and was presumably developed for newer lighthouses created after the advent of electrical lighting, which could benefit directly from much smaller and simpler axial filaments having improved rotational symmetry.
The filament is an axial coiled-coil with a single support, pinch sealed into a double-ended quartz halogen capsule. This is supported by nickel straps welded to a pair of heavy nickel-manganese rods clamped into the copper base posts. There is a fuse wire between the lower leadwire and the frame, sheathed in a ceramic tube for safety. The base consists of a pair of copper thimbles, the ends of which are glazed with borax and a glass bead, and Housekeeper-sealed into a pressed glass cup to which the outer bulb is also fused. It was originally made at Mattoon in USA until 1998 when the Bi-Post lamps were reloacted to Leicester in England. When Leicester closed in 2007 it moved again to Kisvarda in Hungary, and at that time was replaced by the Q1000T7/BP lamp having no outer bulb, and a single-ended halogen capsule cemented into a ceramic base.
| Manufacturer: | General Electric U.S.A. | GE #41734 |
| Lamp Power: | 1000 Watts | |
| Lamp Voltage: | 120 Volts | |
| Lamp Current: | 8.33 Amperes | |
| Cap Type: | G38 | Mogul Bi-Post, copper |
| Bulb Type: | T-63 | T-20 in eighths/inch |
| Bulb Finish: | Clear | GE772 leaded borosilicate |
| Filament Type: | CC-8 1/4" x 1" | Axial Coiled-Coil |
| Atmosphere: | Krypton-Halogen | |
| Luminous Flux: | 22,400 lm (initial) | 21,700 lm (mean) |
| Luminous Efficacy: | 22.4 lm/W (initial) | 21.7 lm/W (mean) |
| Beam Intensity: | N/A | |
| Beam Distribution: | N/A | |
| Colour Temperature & CRI: | CCT: 3050 Kelvin | CRI: Ra 100 |
| Chromaticity Co-ordinates: | CCx: 0.452 | CCy: 0.409 |
| Rated Lifetime: | 3000 hours | |
| Burning Position: | Vertical base down | |
| Overall Length: | 241.3 mm | 91/2 inches |
| Light Centre Length: | 101.6 mm | 4 inches |
| Factory: | Leicester | England |
| Date of Manufacture: | September 2006 | Date Code: 09 |
| Original Value: | USD $25.50 (1972) | |
