Mazda - BTH Type "X" 12v Blacklight lamps (36w and 60w)
I don't usually collect these kinds of low voltage vehicle/appliance lamps, but had to make an exception when I found these listed on Ebay. James H. has published a good write-up regarding these lamps (refer to Lamptech) where he comes to the conclusion that these were an experimental product which saw some kind of use in British aircraft or military vehicles. The presence of the UK War Office stamp both on the lamps themselves and their packaging would also suggest this.

Mazda - BTH Type "X" 12v Blacklight lamps (36w and 60w)

I don't usually collect these kinds of low voltage vehicle/appliance lamps, but had to make an exception when I found these listed on Ebay. James H. has published a good write-up regarding these lamps (refer to Lamptech) where he comes to the conclusion that these were an experimental product which saw some kind of use in British aircraft or military vehicles. The presence of the UK War Office stamp both on the lamps themselves and their packaging would also suggest this.

DSC02406.JPG DSC02401.JPG Screenshot_20260305_124754_Gallery.jpg 20260228_174153.jpg 20260228_171034.jpg
File information
Filename:Screenshot_20260305_124754_Gallery.jpg
Album name:LAllenLighting / Coloured GLS and Halogen lamps
Manufacturer:Mazda (BTH)
Type/Model:U.V./X
Wattage:36w, 60w
Date manufactured:1940s
Filesize:459 KiB
Date added:05 Mar, 2026
Dimensions:1756 x 1040 pixels
Displayed:141 times
URL:http://80.229.24.59:9232/gallery/displayimage.php?pid=24222
Favourites:Add to Favourites

Comment 1 to 5 of 5
Page: 1

Slyspark   [05 Mar, 2026 at 04:22 PM]
I was thinking some kind of military use when I saw the picture. Not sure what other use they'd really have
Flurofan96   [05 Mar, 2026 at 08:40 PM]
I was going to say Counterfeit money scanning use but I don't think the cash notes back in the 40s would have had the hologram or some special mark that shows up only in blacklight. Since the UV output is very low compared to fluorescent I have to say these were for low level lighting to aid the blackout effort
LAllenLighting   [06 Mar, 2026 at 12:12 PM]
You were both close in your guesses - I'm fairly certain these were actually used as back-lights for fluorescent displays in certain military vehicles. However, 60w seems like a slight overkill for that sort of thing, they get bloody hot!
Flurofan96   [07 Mar, 2026 at 10:38 AM]
Oh yes being 60W and the fact these have to be overdriven to maximise the UV output the heat of them would be around 75W or near 100W worth of heat and I'm sure that would become problematic in a tank interior or a plane interior (unless the chill factor of the altitude would help) oh and definately would be used to 'charge up' the radium painted fluorescent dials/displays before deployment
Keiron   [11 Mar, 2026 at 06:01 PM]
Wow, I'd say well worth a place in any collection.

Comment 1 to 5 of 5
Page: 1

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