It would be hard to beat one of these:- https://www.ikea.com/gb/en/p/jansjoe-led-usb-lamp-black-70291232/ plugged into a power bank.I want a portable desk lamp that's powered by some kind of rechargeable battery cell. (A lamp with a normal bulb fitting, not LED.)
Can anyone advise me on this? I'm clueless with electronics and can't solder!
Indeed. A 5000mAh pack should last a couple of days before needing recharge. Good find.It would be hard to beat on of these:- https://www.ikea.com/gb/en/p/jansjoe-led-usb-lamp-black-70291232/ plugged into a power bank.
Thanks!Welcome to ETO!
Thanks but it's way too small and too targeted - I just want to light the room softly with a regular bulb, with a shade.It would be hard to beat one of these:- https://www.ikea.com/gb/en/p/jansjoe-led-usb-lamp-black-70291232/ plugged into a power bank.
Well I just meant a regular lamp that I can attach a shade of my choice to, with a bayonet or screw lightbulb fitting, so I can use whatever bulb I like. In my case, I only use incandescent bulbs.What do you consider "a normal bulb"?
Why not a LED?
That is interesting, though I doubt I would be able to make that kind of modification, unless it's quite easy? Or could you do small modification jobs via the post? (I'm in England too.)I modified an LED lightbulb to run on 5 V, and then the table lamp could be run from a power bank.
How long do you reckon, say, a 20,000 MaH power bank might be able to run an incandescent bulb for? (30 minutes would be useful, 4 hours would be ideal. I don't really need more than that.)For simple flicker-free lighting, ordinary car bulbs will work. You could just run them from any smoothed 12 V supply of sufficient current rating, and there will be no flicker. You will need big batteries to run house lighting if it's incandescent.
A paper that gives a nice explanation of the state of the art without going too deep into quantum.White LEDs are actually blue LEDs with a phosphor that changes some of the light to longer wavelengths.
Power, the wattage, is simply current x voltage.Also, can anyone explain (in simple terms) why bulbs use such a wide range of voltages?
As rjenkinsgb said, there are a lot of different uses for bulbs, and bulbs will only work best on one voltage. A bulb will not last long if the voltage is 10% too high, and will be very dim and inefficient if the voltage is 10% too low, and bulbs already have quite a short life and are quite inefficient already.Also, can anyone explain (in simple terms) why bulbs use such a wide range of voltages? Is it simply that bright bulbs need lots of voltage?