yaaaay lightbulb and Routemaster stuff
thank you for posting that,
I found it very interesting, (I do have Somewhere... a Lightbulb guide for Routemasters from one of the RMOOA magazines i got back in the day)
tis very cool that you have some orignial LT ones, im actually not 100% sure on who made those
I had a couple from RML2760 (given to me by the conductor not stolen!) sadly 1 broke, and the second I got to replace that one, sadly met a very explosive end when I failed to realise my Variac (Variable voltage auto transformer) was set to 270V and not 24V....
I would love to get an orignial LT example (and a new modern one) for the collection at some point
from examining the features I want to say the LT examples where made by GEC in Shaw, Oldham, I am not sure who made the moderns, I would like to hope they where made by Victoria lighting (which was a small company setup to produce special types made by GEC, when GEC got bought out and the rest of the factory sent overseas), but I dont think they have made lightbulbs here since 2003
interesting that your head lights are 12V, when I was at Routemaster 60 in 2014, I handed over far too much cash to one of the stalls there selling bus parts for some Lightbulbs, (for both the collection and as a memento) and both types of Headlamp bulbs I got where 24V (but then again the saloon bulb he sold me was 60W! rather then 22W, which I know is wrong, and is quite naughty given the potential to heavily overload the wiring if you outfit an entire bus with them)
as for the ones that go dim, id try giving your lamp holder contacts a good polishing, as they are probably a bit oxidised after 50 years of use (and on the original lamps, giving the solder contacts on the base a light reflowing)
Cool see you have the inside illuminated advert as well as your rare external ones
do you have pictures of the old tube that failed the light? im curious if it was actually at EOL or if you just had a bad ground or such preventing it from starting properly
(the early electronic ballasts are designed for T12 tubes only and only put out a 200-300V OCV to strike the tube, so you need a good ground going along the tube to ensure they strike up properly, they actually made/make T12 tubes with a painted metal stripe along the tube connected to one end cap shell that you can ground incase you cant mount the tube near a grounded metal surface, you can actually see the metal toung that does this in your picture showing the lamp holder, but getting ahold of those special T12s is quite tricky these days as even regular T12 tubes get thin on the ground)
which is why the old tube glowed brighter when you touched it, because you where providing a grounding path helping the tube conduct electricity slightly easier
I have recorded such phenomena happening here
if your wondering, that Osram 20W T12 was made made by Philips at their Hamilton Factory up in Scotland in (date code is N0b8 ohhh errr ) November 2000
(you can easily tell its a Philips made tube for Osram even without the date code or such, because of its classic Philips stepped end cap design)
heres some Warm white Sylvania tubes if your interested in stocking up on T12s for it (Warm white too should match with the tungsten saloon lighting better) https://www.ebay.co....tm/322044243194
I wish I could pop round and get all 5 of the tubes in the advert working (also very curious to see what tubes its rocking)
Thanks for the detailed reply (I wouldn't have expected anything else!). A few points from above. Taking the bulbs out and cleaning the contacts would be a good idea if it wasnt for the afforementioned fact that if you try and remove the original ones the glass bowl will come off in your hand leaving the brass bayonet behind. I know I should stop being a skinflint and buy enough new bulbs to do the whole bus but I like the fact that some of these bulbs are over 30 years old (and possibly considerably older than that). If it was still in service I would probably have to replace them but as it only gets a class 5 MOT they dont even try the interior lights.
The interior fluorescent tube I took out had no markings at all. Thanks for the link, 25 of those would last me about 300 years, but it's good to know they're that cheap. Be useful if I had an RMC or RCL, they do have fluorescent saloon lights. One day...
As for getting the exterior advert going, I know it wouldn't take much, simply holding them as your clip shows would probably work. There's just one problem there - they are behind three big perspex panels. The bulbs are essentially on the outside of the bus with the three perspex panels held in place with a rubber seal a bit like an old car windscreen rubber which inevitably leaks. It's little wonder they were so unreliable in service.
To get these panels out you need a scaffold tower and ideally two people. I last took it out in 2006. The advert you see in the picture, I had made by a local sign company. I chose this partly for its simplicity and partly because my bus carried this very advert in 1985/6. It was very common at the time on the illuminated advert buses. The sign company gave me some large sheets of yellow vinyl and did the lettering separately. I took the three panels home and layed them out down the garden path to apply the advert.
Unfortunately one of the panels snapped in half when I was getting it back out of the car but the vinyl held it together so we put it back in the bus as it was.
The advert has been on there over 12 years now and is looking a bit tatty. It does need replacing, then we could sort the fluorescent tubes out properly but I seem to have about a hundred more pressing jobs to do first.
Looking again at this picture,
it would appear that each tube is roughly the same length as a window. This would make each one about four foot long. Does that sound right? Four times four foot and a two foot one at the back would make the advert panel nearly nineteen foot long allowing for a small gap between each one. On a 27' 4" bus that looks about right. Are four foot tubes still readily available?