An LED replacement for an old torch bulb
Many of us have an old torch (flashlight) or maybe an old cycle lamp that uses a traditional flanged “Prefocus” bulb. In my case I've a Duracell (4C) torch with a swivel lens that’s mainly used for DIY or emergencies. I keep it in the garage for the times when I have to stumble around in the dark to find the circuit breaker that's tripped when yet another lightbulb blew.
Problem is, like all such old-fashioned incandescent lamps Prefocus bulbs are inefficient and need good batteries to get the best out of them. The four expensive Duracell ‘C’ cells in my torch are past their prime and I only get a faint yellow glow whenever I use the thing.
However I’ve found the perfect way to upgrade it using an LED Replacement Bulb marketed by the US firm Dorcy International. These hard-to-get bulbs have the same metal base as an old Prefocus type, but they have a powerful white LED instead of a filament. Different voltages are available for 2 cell (3V) or 4.5-6V lanterns and they claim 100,000 hours of life. My 4 x ‘C’ cell torch therefore needed the 4.5-6V type and it claimed a 40 Lumens output.
The Dorcy LED Replacement Bulb fits perfectly and even using the same tired ‘C’ cells the light output is very much brighter as my photos show. They are a bit hard to get. They might be available from e.g. ebay but beware very high postage from the USA, or try the Amazon UK links below.
I guess the time will come where the battery voltage finally drops off and the bulb fails to light, but until then it’s an excellent way of giving a traditional torch a new lease of life.
Suggested Dorcy 41-1644 40 Lumen 4.5V To 6V Led Replacement Bulb
Suggested Dorcy 41-1643 30 Lumen 3 Volt LED Replacement Bulb
These Dorcy LED bulbs were formerly available on Amazon and Ebay, but since writing this article Dorcy LED bulbs have become more scarce in the UK. The biggest problem is the high P&P from Amazon 3rd party sellers which makes an upgrade less economically viable, and the unfavourable £/$ exchange rate doesn't help.
However a different brand is listed, a 1W 120 Lumen type claiming to be non-polarised (which is better, as it no longer relies on which way round your batteries are wired), and it's 1-9V. Worth a look.
AW