GEC 'Nightwatch' Z9538

Lantern acquired in March 2008.

Yet another lantern from GEC's popular Group 'B' SOX range enters the collection - this being the side-entry, gear-in-head version for 55 Watt lamps (although 35 Watt lamps would also fit). The capacitor in this example is dated to July 1989, which, assuming that the lantern is of a similar age, possibly makes it one of the last lanterns to bear the GEC name. The lantern does not appear to have been used, and whilst its history is not exactly known, it has been in storage for a long time.

 If you position your mouse cursor over the highlighted photographs, the image will change for the equivalent one showing the OSRAM Z9536 (the gear-in-base version of this lantern) in my collection - in this way, both lanterns can be compared.

As both the Z9538 and Z9536 have not been installed outdoors, the canopies are both smooth and clean. The bowls on the two lanterns are clear and colourless, unlike the majority of installed Z953# lanterns, whereby the polycarbonate bowls have yellowed somewhat!

The Z9538 is fitted with a (capped-off) NEMA socket, whereas the Z9536 is drilled for a two-part cell detector. Notice also how the GEC logo has been blanked out on the canopy of the Z9536.

Whilst the bowls appear to be very similar, there is a tiny difference between the two: again, all GEC references have been removed on the OSRAM lantern.

The lamp fitted in the Z9538 is a Philips from December 1991. Click here to see an alternative photograph of it.

Even though a gear tray is not fitted in the Z9536, the canopy still has the two threaded fixing holes which hold the hinged tray in place on the Z9538. Whilst the Z9538 has never been used, the wiring has been altered, in order that the NEMA socket is bypassed. Whilst the lamp support in the Z9536 is the 'standard' GEC type with a 'C' shaped piece of metal joined by a spring, the support in the Z9538 is simply a bent strip of metal.

The identification labels on both lanterns are in the same back corner. A noticeable amount of white space is present on the Z9536's label! The internal components of the Z9538 have corroded in the damp atmosphere where the lantern was stored, however none of the screws appear to be seized.

With the gear tray moved out of the way, the underside of the Z9538's canopy is seen. This view shows the two gear tray fixing holes, as well as a central fixing hole which is for the lamp support on the Z9536, and therefore is not used on this version.

The Z9538's gear was a real surprise to me due to it being made by Philips and not GEC! Had GEC gear been fitted, it is likely that a Z1616 ignitor-ballast would have been fitted in about the same place as the Philips ballast is here. The capacitor is dated to July 1989, and is made by Cambridge Capacitors, although it carries the GEC code of 'Z1757'.


The lantern was fitted to a wall bracket on Monday, 18th August 2008. As the photographs show, this is a very small bracket - the lantern only just fitted! Another unusual feature of this bracket is that it has a zero degree tilt, when normally a minimum five degree tilt is employed, in order that the lantern does not appear to be falling off!

The lantern was then powered up - despite being seventeen years old at this stage, the lamp worked perfectly:

The Z9536 and Z9538 both look very similar when powered up, although of course the Z9538 will have a bit of light reflected off the gear tray during operation.

Lantern warm-up video:

Philips MI 55 GO | Thorn Beta 5


Lanterns in the Z953# range in collection

Z9531 Z9532 (aluminium) Z9532 (GRP) (1) Z9532 (GRP) (2) Z9536 (aluminium) Z9536 (GRP) Z9538 Z9539




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