The Netaline has to be one of the slimmest (and lightest) fluorescent luminaires ever produced, and for saying that it is also one of the most simple in terms of its construction, is also one of the most iconic.
The fitting is designed to run 4 ft (1200 mm) 40 Watt 'T12' (1½″ / 38 mm)-diameter lamps; as can be seen, for much of its length, the lamp is the widest part of the luminaire.
An ingenious method of providing a ballast for the lamp is employed - rather than there being a dedicated choke, a length of resistor wire exists in the channel linking both ends of the lamp. This massively reduces the weight of the fitting.
A Bakelite cover conceals the Netaline's ceiling fixing plate; this can be moved out of the way during installation.
A length of (possibly original) flexible cable was supplied with the fitting - notice that the core colours pre-date the modern colours of brown, blue and green/yellow. For flexible cables, the change to the new colours was introduced in 1969.
A slightly cranked tube links the ceiling fixing plate with the main body of the fitting.
The small pod at the rear houses the starter switch and very little else. A tactile thumbscrew secures the cover.
An OSRAM lamp was supplied; this was made in August 2007 at the Philips lamp factory in Hamilton, Scotland.
The starter area cover is spring-loaded, but given the fitting's age, the spring is now rather stiff; this is why the cover was removed completely for this photograph. The two lampholders are loose, and only the construction of the luminaire holds them in place during normal operation.
The lampholder at the other end tucks into the assembly, hiding it from view.
The Netaline was fitted on Monday, 20th June 2017. Prior to its installation, a new length of heat-resistant (that part was crucial!) flexible cable was connected; replacing the old non-compliant supply cable. At the point where the cable entered the rear 'pod', a length of heat-resistant sleeving was placed around the cable sheath, as a further protection against high temperatures. The missing earth screw on the ceiling attachment was replaced with a new 5 mm brass screw, whilst the worn-out glow-starter was replaced with a modern Arlen EFS 120 electronic starter. Although this type of starter is intended for use on twin-lamp circuits running in series from a single ballast, it also provides a more gentle pre-heating start for a T12 lamp than the regular single-lamp EFS 600 unit does.
Owing to the Netaline's ceiling mount being narrower than a traditional ceiling pendant would be, a white plastic cover had to be installed between the fitting and the ceiling, or else an un-plastered and unpainted mark from where the original pendant fitting had been located would be visible.
The 1960s' adverts for the Netaline suggested that it could be fitted to an existing ceiling lighting point in only five minutes, without requiring any alterations to the existing wiring. While the latter is largely true, the former wasn't in the case of this example - modern loop in/out wiring ensured that installation took a little longer than the estimated timescale!
Within only a short time of the Netaline being switched on, the characteristic "burning dust" smell normally associated with electric heaters that haven't been used for a while was detected in the room. Unsurprisingly, the resistor wire providing a ballast for the lamp was the culprit - this became surprisingly hot during use, which would have the benefit of providing additional heating to a room when the fitting was running during the winter months...not mid-June, when the room temperature was already rather warm!
The design of the Netaline ensured that the ceiling served as a convenient reflector for any light that passed upwards.
The video below demonstrates the Netaline operating; notice that the switch-on resembles a Semi-Resonant Start fluorescent circuit with the EFS 120 starter employed.
Prior to installation, the Netaline was tested with my energy monitoring device. This revealed the following results:
| Test Voltage (V) | Current being drawn at full power (A) | Measured wattage (W) | Apparent Power (VA) | Frequency (Hz) | Power Factor | True Power (W) | Difference to rated wattage | Percentage Difference |
| 241.3 | 0.43 | 100 | 104 | 50 | 0.95 | 98.57 | 58.57 | 146.43% |
Yes, whilst the resistor wire ballast allows for an altogether lighter product, the downside is that this is a very inefficient setup, with the current draw being approximately double that of a conventional 40 Watt lamp; still, I understand that I can run the fitting for seven hours and it will only cost me one (old, pre-decimalisation) penny in electricity costs...bargain!
For variety, I tried my other two 40 Watt fluorescent lamps in the Netaline - the GE Blacklight, and the red-coated Thorn. Oddly, whilst the GE worked perfectly, the Thorn proved very problematic to operate on the resistor ballast - the EFS 120 starter kept shutting it down soon after power was applied, and when this was substituted for a brand new glowstarter, the lamp's ends glowed, and the starter made some audible pings, but striking an arc proved difficult. Therefore, the following couple of pictures demonstrate the Blacklight's operation only.
With the flash activated.
It's a shame that the red lamp proved so camera-shy (it did work, but of course, this was only when the camera wasn't set up!); it looked rather suited to the equally-ruddy rear section of the Netaline.
The following video shows the attempted start-ups of both lamps.
Sadly, the key to the Netaline's operation, the resistor-based ballast, failed in October 2018. This required the fitting of a conventional 40 Watt fluorescent choke, and re-wiring of the lamp circuit. Fortunately, the channel above the lamp is perfect for securing the choke against, and situating the choke at the 'connection' end improves the overall balance considerably.
The insulation surrounding the resistor wire was in poor condition, with much of it cracking or having flaked off completely.
This close-up reveals the closely-coiled nature of the wire, along with the miscellaneous white fibrous insulating material that forms its centre core.
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