Manfacturer: Philips Lighting Co.
Here's an early Philips branded mercury lamp, circa 1984. Only made a little over a year after Philips purchased Westinghouse's lighting division. Westinghouse HID lamps continued to be marked with the Westinghouse name throughout 1983, but HID lamps from 1984 onwards began to be branded with the Philips name. This lamp has the Westinghouse BT-28 shape and internal construction, the ONLY difference is the new Philips etch. Changes as a result of the Philips takeover did occur a few years later, as during the years of 1986-1989 Philips switched over to the E shape for the majority of the HID line. Unfortunately quality gradually declined as the old, Westinghouse large Lifeguard electrodes were finally eliminated around 1994, replaced by generic, small electrodes which are prone to rapid blackening. But these days manufacturers are doing research on HPS and Metal Halide lamps, and mercury lamps are no longer a value added product, so this is probably the reason. At least the Made in USA thing still lives on with Philips mercury lamps.
This particular lamp has a very thin phosphor coating on the end, so it could almost qualify as a cleartop! It was used for years in a dusk to dawn fixture but still works very well.
Lamp: Mercury Vapor
Wattage: 175 watt
Starting Voltage: 240 volts
Operating Voltage: 130 volts
Ballast Type: H-39
Color Temperature: 3700K
CRI: 45
Light Output: 7800 Lumens
Bulb: BT-28 Hard Glass
Finish: Deluxe White
Base: E-39s Brass Mogul Base
Class: -
Filament: -
Lamp Life: 24,000 hours
Manf. Date: August 1984
Country of
Orgin: USA
