Tube Night Light

[KerryF]

Hey.  Not sure if this goes here, but you can move it.  Yesterday I was checking out one of those little night lights that plugs into the hallway outlet.  The thing goes on when its dark, and off when its light.  I put that all together in my head and im like wait a second, thats an LDR in there.  So I thought about a cool idea, which im sure people have done before.  You can use that little enclosure that plugs straight into the outlet with the LDR to use a tube, instead of a light bulb.  I am planning on opening this one up today (I tried with a screwdriver, and a screwdriver bit on a drill, but its really tight, and just striped the screw, so my dad is going to drill through something to get it open).  Anyone have a schematic on how to how to hook this up?  I would guess to put a tube socket in the place of the light bulb socket.

Heres pictures of the thing:

[GibsonGM]

Ha ha, that's a great idea, 800!  I bet that bulb runs on 120VAC, tho...so, you'd have to step down the 120 to 12VDC and rectify it.  You'd also have to know what current will make your tube glow and plan things around that for biasing.   Of course, I'm assuming you'd be using something like a 12AX7 preamp tube!  To convert that to use a power tube would be different - I'm just thinking a power tube would be too big & clumsy, subject to damage...

Found a PDF for 6L6GC's (typical power tube)...seems like they want about 250V to operate correctly.  I don't know what voltage they start to glow at, LOL.   Someone more in the know will come along with more info...

[KerryF]

^-Thanks. Yea, I thought it was a really cool idea too.  I just dont really know how to do it.  I will wait for someone who knows.

[markm]

 
That's great!
I love that idea.....800, U R Dangerous!!

[saemskin]

I can see this idea getting out of hand really fast. 
Refrigerator tube lights, thos fake smelly candle tube light, tubes instead of led's on EVERYTHING

AAHHHHH

[KerryF]

haha exactly!  well, it would be a good buisness

[zachary vex]

it may be possible to find some old tv or radio tubes that operate at a higher filament voltage.

[RLBJR65]

Couldn't you just use a small bridge rectifier and a 12 volt regulator?

[MetalGod]

make sure you use NOS tubes - the filament glow in new tubes just doesn't look right to me 

[billings]

Wikipedia randomly informed me the other day that the old mass produced radios operated without transformers at all:

http://en.wikipedia.org/wiki/All_American_Five

So like zvex said, you can find appropriate tubes in those.

[idlechatterbox]

AA5s run with a hot chassis, no transformer, unless you install one.

The night-light tube project sounds cool. You're lucky you have a dad that "enables" your insanity! Most would say something like "you want to drill WHAT?!" 

[KerryF]

haha.  so my dad just drilled through the screw.  never knew that if you drill through the head of a screw, it comes apart.  we got it open!
Pictures:
The enclosure:


The very simple circuit board:

The very strange and mysterious 0.00 ohm resistor:


So, all I really need now is a schematic for how I can actually get a tube to work with this...  Hopefully someone here will come up with something for me  .

[KerryF]

Just found this schematic: http://www.electronixandmore.com/project/2.html .  It says to use a OA3 tube, but where can I get one?  How much would it be?

[Tubebass]

0a3 is a gas regulator tube and has no filament. It lights up sort of a purplish colour.Antique Electronics should have them.

[idlechatterbox]

I buy tubes from a guy on ebay. E.g., ebay item number: 160030764599

He has something like 1000 tubes   and gives you options, like do you want new, used, in box, etc. He also will let you know if there's a sub for the one you want, if this or that tube would be quieter or otherwise different. Cheap and tested to work. Even though he sells on ebay, I just email him with what I need, no auction. You only need one tube, so I guess if you're interested you could just drop him an email and describe what it is that you want to build.

Just a suggestion. I guess everyone has his/her trusted tube supplier of course. Either way good luck. Sounds like a cool project.

[KerryF]

thanks...  anyone know how many pins the OA3 has?

[Tubebass]

Seven.

[KerryF]

Then wheres all the pinouts on the schematic!? 

[Gilles C]

http://www.electronixandmore.com/project/1.html

[RLBJR65]

Data sheet.
http://www.mif.pg.gda.pl/homepages/frank/sheets/127/0/0A3.pdf