The strobe effect produced by tubes is caused by the voltage dropping at the end of each half cycle. It can be reduced in effect by the use of different powders in the tube - having a greater afterglow. It is normally only noticed in the presence of rotating machines (until these lousy lamps came into use!) and was traditionally cured by using a twin tube fitting with each tube being knocked out of syncronisation with the other electrically by using a lag - lead circuit arrangement. One manufacturer of fittings claimed that due to the vastly improved tubes they used, such fittings were not necessary. Strange that, in our machine shop, I would have sworn blind that we obtained a strong strobe effect on the lathe chucks - but maybe that was just my eyesight
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The function of the choke (the big laminated iron core) is twofold (a) to produce a high voltage at start to strike the tube (b) to limit the current during normal running. Without a means of limiting the current, the current would rise rapidly and strip the anode of the tube and possibly rupture the actual tube.
Re the power factor question raised by Stallspeed
Scottish Hydro are giving out complimentary Philips fluorescent bulbs so they can't have heard about power factor
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If you consider supply networks, low(er) power factor is really only a problem on the lower voltage systems as (in extreme circumstances) it could involve having to upgrade supply cables and transformers to cope with the extra current demand. As the system voltages increase, i.e. as you go back through the system toward the generation point, the system has a larger capacitive component built into it by it's very design. Their worry is not low power factor but rather the opposite - a leading power factor. In the big picture, the percentage of the total system load due solely to domestic lighting is small.
The point I was making was not the power factor involved but rather the increase in the load on the system in terms of the Volt Amperes.
If this is old news to you - please ignore!
The common voltage 'grid' is fairly recent - some of you must remember the changeover.
The event you are refering to was agreed in the U.K. in the mid 1920's.
Because of the costs involved, some of the old systems still hang on. Quite often they are a hangover from the system used to supply electricity from the local tramways systems - so even in large cities, you can find oddities. How about cable systems formed by having a wood trough filled with bitumen with lightly insulated copper conductors laid inside the trough? Sorry, going off topic.