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A few years ago i saw this little beauty [http://www.thetubelamp.com//photos/tags The Tube Lamp] pop up online, designed by Nik Willmore and decided it was exactly what i needed for my little Mad scientist Laboratory. unfortunately i couldn't spare the disposable cash needed (or justify it) to purchase such an item, though i would still like to some day as his still has a captivating hold on me :)
This is project to show you how to make a much more cost effective version of the tube lamp design to get you by for the meantime. Rough estimate of the costs involved in this project is totaled at around or under $20 depending on the supplies you choose.
NOTE: I Have updated some of the steps to help clarify some things and changed the way certain things are setup so they are more efficient and easier to understand. and from now on i also won't wait as long between doing a project, taking the pictures, and then making the write up as that leaves too much room for error :) thanks for reading.









































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I don't have any problems with sharing the schematics, as a matter of fact, I'd love to =) (all information should be free) That's why you can find it at my website: phobos.50webs.com/elektroweb/madscientistlight.html (take a look at the original sketch). I noticed I still haven't provided any additional information on the site so here some extra notes; The flashing is done using ordinary fluorescent light starters. and I used a very basic dimmer ciruit in series with the rest of the circuit (that is switches, starters and bulbs).
The components for the dimmer are:
- standard Diac (like a DB3)
- Triac (anything will do as long as it can handle the power of the bulbs, like a TIC 206 or BT136)
- 470K potentiometer
- 0.1uF capacitor (50V type should do fine, but I usually use a 250V or 400V type just in case one of the other component should fail)
you can find the dimmer circuit at the bottom of the sketch.
If you have any questions just let me know.
Ow, and if you build one yourself, I'd love to see it!
http://www.instructables.com/community/I-Made-It-Challenge-Is-Back-Win-A-Pro-Membership/
I am a novice at electrical stuff, so your guide really helped me to go above and beyond once I understood the principals. The Box on the right is my first, the second is made with Christmas lights and vintage doctor office test tubes and the third has a dimmer, stand-by light and working clock. I couldn't have done it without this instructable!!!
just picked up 10 of these beauties for a project
Something like this, though I don't know that voltage you have in your country.
http://cgi.ebay.com/Color-Lux-15W-watt-Clear-Aquarium-Bulb-E26-Medium-Base-/290514121789?pt=LH_DefaultDomain_0&hash=item43a3fdb43d
How are these bulbs named ? I dont find them in my local hardwarestore.
regards from Hamburg (DE)
but too hard for me
for my baby would touch anyting in my room.
so wiring in paralel have advantages: 4times more power to each bulb
and wiring in series also have advantages: 4times less power consumption thant series wiring
Volts x Amps = Watts
Wattage=Power Consumption
The power consumed by the lights will not change dramatically by wiring the lights in series or parallel. The lights "require" a specific wattage, eg. 60w, and besides adding a dimmer, will just "automatically" get it.
By wiring the lights in series, you increase the amount of resistance in the circuit, and this reduces the voltage like was pointed out already. But it does NOT reduce the amount of power you are using. If you refer the the formula I wrote above and keep in mind the Wattage is going to be constant, you can understand how when the voltage decreases the light will respond by increasing the amount of amperage. In fact this is how many house fires are caused because amperage causes heat. The old christmas lights without the fuses could get so hot they'd melts when you plugged to many strings into eachother like this.
The ONLY way to reuce the power consumption in a light circut like this is with a dimmer, and not all dimmers qualify. The modern Levitron dimmersw you pay about $20 a piece for DO reduce the power consumption, but the old style only reduce light output and not consumption.
Hope that was helpful :)
let calc internal resistance of the bulb
R=U/I
U=120v
I=60/120=0.5
R=120/0.5=240 omhs
now let see if at 60volts it stay at 60w (60volts 1 amp)
I=U/R=60/240=0.25
0.25*60=15w
as you can see, according to ohm law, if voltage to buld decreasse, amp decreasse too
The reverse is true. Standard batteries are 1.5 volts each. Wire them in series and the voltages add up. Lots of items use 3 batteries wired in series to produce 4.5volts. Close enough to power electronics meant for 5volts.
It's not quite as simple as four times as many bulbs = four times the resistance = one quarter of the current, because the resistance of a lightbulb depends on its temperature, so a lightbulb driven at half the voltage will draw more than half the current. With longs strings of bulbs in series (like the old christmas lights), sometimes you can see them initially turn on brightly when the string is cold and at a low resistance, then dim as they heat up and increase resistance. In this case, the effect would be quite mad-scientist-y anyway :)
Put the bulbs in series, 2 in series will run them at half the voltage. They WILL take less power. If the brightness of 2 bulbs in series is the same as using a dimmer then the power taken should be the same.
Forget Ohm's law with bulbs, the resistance (R) is not constant! A hot bulb has a higher resistance than a cold one!
Also make sure the bulbs are the same wattage or the power (and hence brightness) will be shared unevenly.
I wired 2 sets of old Christmas lights in series for my parents (about 10 years ago) - the brightness looks about 50% less (approx !) but the bulb life is MUCH longer!
I remember quite a few of these old (approx 60 years!) bulbs failed when I was a kid, but none of them have failed since!
Bulbs are not transformers, completely different
When the resistance goes up then the current goes down!
I(current)=V(voltage)/R(resistance) (Ohm's law)
If you have a 100W bulb running on 110v, it will take 100 Watts ONLY when running on 110v.
If you run it on a lower voltage then it WILL take less current!
Try this simple experiment...Switch on the headlights of your car then start the engine. As the starter is turning then the lights dim (the voltage of the battery is dropping) then the engine starts and they are brighter (higher voltage-battery on charge!)
The brightness IS proportional to the actual watts being consumed by the bulb.
When we put 2 bulbs in series, the same voltage is shared between 2 bulbs. Twice the resistance*, Half the total power consumption, each bulb running at a quarter of the wattage*
*I mentioned earlier that a cold filament is a lower resistance than a hot one so this isn't exactly true but it gets complicated here!
I hope this helps!
Cheers,
Andrew