Philips MI 50

Lantern acquired in July 2007.

This lantern is the precursor to the Philips MI 26/XGS 103 and as a result, is similar in appearance - indeed, both lanterns use the same bowl. The capacitor in this lantern is dated to 1989 which would probably be when the rest of the lantern dates from as well. The MI 26 first appeared in the early 1990s although the MI 50 (and its 70 W SON version, the MI 55) were still being made until recently.

Like my MI 26, this MI 50 also uses a vacuum-formed bowl.

The canopy is similar in shape and appearance to that of the modern Thorn Beta 5.

The vacuum-formed bowl means that the appearance of the lamp is even more refracted than normal!

A silver label on the inside probably provides most of the reflection on its own!

The original Philips ignitor has been replaced with a Thorn one at some point. The original ballast and capacitor remain, however. During maintenance,  the gear tray would originally have been supported by the two plastic strips visible inside the canopy but these have perished over time.


The lantern was fitted to an AC Ford AC872 wall bracket on Sunday, 22nd June 2008. It was then powered up...however, nothing happened. After disconnecting the supply (and receiving a most enjoyable shock from the discharging capacitor!) I set about trying to figure out what wasn't working. As the ignitor was fairly new, I tried it on another circuit and it worked perfectly - meaning that the ballast was the faulty component. This soon became obvious when I tried to remove the output wire from its terminal - the terminal simply broke away and revealed a rather charred internal connecting wire! Fortunately, I had a spare Parmar ballast that could be installed using the existing fixing holes, so the two were duly swapped.

The old ballast can be seen ledged on top of the bracket.

With the lantern back together, I powered up and hoped for the best. This time the lantern sprung into life:

Lantern warm-up video:

Philips MI / F/XGS Lanterns in the Collection

FGS 103 (June 2003)

FGS 104 (Oct 2002)

MI 8

MI 26 (June 1992)

MI 26 2 (June 1998)

MI 26 4

(Feb 1998 / Sept 1999)


MI 50 (Feb 1988)

MI 55 (Aug 1989)

MI 80 (Oct 1985)

XGS 103 (Oct 2001)

XGS 103 (Dec 2002)

XGS 104 (Oct 2002)

GEC 'Difractor' Z8128B | GEC Z9532




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