Philips MI 8

Lantern acquired in March 2005.

The original location for this lantern is unknown, but it was used in the City Council area. I can't think of the locations of any for now, but that isn't surprising as I don't think that the lantern was made for long (it may have been used in Stenson Fields, although this isn't technically in Derby City, but Derbyshire County). This lantern should not be confused with the MI 80, another lantern made by Philips, despite the fact that both can accommodate a 55 Watt SOX lamp. This lantern may have been 55 Watt in the past, but it was 35 Watt when removed, and looks as if it had been for at least a few of its latter years. This lantern is also known as the CU Phosco P224/6, and appears to have been sold under licence by Philips until the MI 80 (along with the MI 50, MI 51, MI 55 and MI 57) became available in 1981, when the MI 8 was withdrawn from catalogues.

The lantern is in need of a clean, but apart from that, it is in good condition.

The shape of the lantern is not dissimilar to that of the GR100.

The gasket around the bowl has come away in places, meaning that dust and moisture has been able to enter the lantern.

Opening the bowl shows a real mess of cables entering the lantern. The fragments of plastic at the other end are the remains of one of the terminal blocks - the plastic has perished from the years of heating. The rest of the terminal block is also very brittle, and will be replaced for safety. Visible towards the front of the lantern, cast into the canopy, is 'P224'.

With a lamp fitted, the length of the lantern becomes obvious. The mark left by a 55 Watt lamp can still be seen at the end of the lantern, so one has definitely been used in the lantern in the past.

A spare bowl came with the lantern in case the existing bowl cannot be used for whatever reason.

The bowl still has its manufacturer's label in place - this will be left there as it would probably not come off in one piece, having been on there for so long.

The MI 8's gear consists a very new (31st August 2004) Parmar ignitor-ballast and GEC Z1757X capacitor dating from week 15 of 1980 (the 7th - 13th April), which gives a possible indication as to the lantern's age (indeed, the lantern is listed in my 1979 Philips catalogue - pages 6 - 8). The original ballast was probably the GEC version, the Z1616. A gear-in-head version was produced, which used the deeper canopy of the Phosco P226, but was still known as an MI 8 when sold as the Philips product.

Restoration of the lantern commenced in late 2021, with the first task being to drill out the rivets that held the bowl to the canopy. After that, the canopy was sent to R.L. Dumelow & Son, of Burton-upon-Trent for bead blasting and repainting. The exterior was repainted light grey (RAL 7047 - Telegrey 4), to match the (apparent) original finish.

Meanwhile, the interior was treated to a fresh coat of gloss white paint.

The existing bowl was cleaned.

A deposit that had formed on the underside of the bowl that seemed to have affected the plastic, and couldn't be removed.

A new lamp support hook was produced by TAS Engineering, of Burton-upon-Trent. For saying that this is only a small component, it proved problematic, thanks to its 10-32 imperial thread - the original assumption was that it was the metric M5 thread, and a hook was threaded accordingly, as were several others that had been made as spares. Fortunately, there was sufficient rod left over for another to be produced, with the imperial thread cut this time. (If anyone can use one of the spare M5 hooks, contact the company for more information). The old, twisted hook is seen on the left, while the replacement (complete with the length of insulation sleeving, and locknut, from its predecessor) is on the right.

The replacement lamp support is seen within the reassembled lantern, complete with a brand new 55 Watt SOX lamp for it to support, and a new self-adhesive foam gasket around the inside edge of the canopy.

The bowl had been re-riveted to the canopy by this time.

The lamp remains partially visible through the bowl's prismatic refractors.

The completed MI 8 was installed on a wall bracket on Monday, 3rd September 2022.

With the lantern installed, the bowl's rather angular front could be appreciated.

In this view, the MI 8's half-sibling, the MI 26, is visible in the background.

The lantern was wired up to a remote Z1616 ballast, and new 6·3 µF capacitor. The Z1616's ignitor circuit produced a considerably loud buzz during the lamp's warm-up.

Once the lamp was at full power, the buzz volume reduced considerably, as the ignitor circuit deactivated automatically.

The bowl diffused the lamp's output nicely.

Lamp warm-up video:

GEC Z5680 | Abacus AM 202

CLICK HERE TO MAKE A MONETARY DONATION