This is an idea for a more compact, compact flourescent light. It comes in three parts: the ballast, and the adapter, and the lamp.

The ballast would plug into the wall, and have a recess in it, into which the lamp's original plug would be inserted. The lamp's original plug would be held in place semi-permanently, by a screwed down cover.

The adapter would then go into the light bulb socket (either using an edison base screw, or a bayonet base, or whatever's appropriate for the original lamp). This adapter would be designed to be easy to put in, but difficult or impossible to remove. This adapter would be designed to fit wholly inside the regular lamp socket, so as to take up a minimal amount of room.

Into the adapter, one would then put a flourescent lamp (either u-shaped or spiral), probably with a two pin base.

The adapter of course would be designed to only work with flourescent lamps approriate for the ballast.

The flourescent lamps would *not* be specialty lamps, but ones already available, and thus readily purchased, in hardware stores in the country/region where the device is marketed.

Although the adapter wouldn't be removable from the light fixture, the flourescent lamps would be easy to change, and, with the aid of a screwdriver, it would be possible to replace the ballast, too.
-- goldbb, May 18 2009

with the caveat that the ballast would destroy any sensitive electronics that were plugged into it.....
-- WcW, May 18 2009


Since the ballast's outlet is recessed into it, and there's a cover over that outlet, and the cover is held in place by screws (possibly by tamper resistant screws), the odds of someone accidentally putting something into that outlet that shouldn't be there are relatively low.

Especially if appropriate labeling is used... something like, "Do not insert any device into this outlet, except for the plug of a lamp equipped with properly installed GoldCO(tm) flourescent adapters. GoldCO(tm) holds no responsibility for injury or damage in the case of inappropriate devices being plugged into this ballast."
-- goldbb, May 19 2009


There are usually more than two connections between the ballast and the tube, because there's a filament at each end and you need to first preheat each filament and then run an arc from one filament to the other, meaning four connections. How would this be accomplished? Maybe a thermal switch inside the lamp part?
-- notexactly, Mar 30 2017


Answering my own question. Wikipedia's fluorescent lamp article says:

// In most CFLs the filaments are connected in series, with a small capacitor between them. The discharge, once lit, is in parallel to the capacitor and presents a lower-resistance path, effectively shorting the capacitor out. //
-- notexactly, Mar 30 2017



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