Geiger Lamp - Now with Illuminated Dial

This Instructable will document how I converted an old civil defense Geiger counter (O.K. technically it's an ion chamber, but most folks haven't heard of those so we'll just call it a Geiger counter) into a lamp. Why do this you may ask? I work in a field which touches on radiation and we just moved to a new work space that isn't quite as well illuminated, so I decided to make a radiation themed lamp. I had seen this done before, but didn't like the way the conversion was done. That version had the meter horizontal so you couldn't see it very well and used a pull chain socket. My version has the meter vertical and I use the original instrument knob to turn the light on and off. Plus the guy who made them was charging an exorbitant amount of money for them. I figured instead of paying for something I really didn't like I would make my own for less than $20.

I haven't added a shade at this point, but that will hopefully be rectified soon. I think I'll try and find one that is yellow and black or yellow and magenta as these are the official color schemes for radiation postings in the U.S. I've also considered making a stained glass shade in these colors, but that will have to wait for warmer weather. Whichever option I go with will play on the radiation theme.

The green twist is that this project uses almost all reused materials. I only bought a new socket, nuts to hold on the feet, and a new rotary switch.

Step 1 Materials

These are the materials I used to make my Geiger Lamp:

• 1 survey meter ( I used a CDV-715)
• A cord with a plug
• White wire
• Black Wire
• A rotary switch (On/off not reostat)
• Wire nuts
• Electrical tape
• Feet (4)
• Nuts (4)
• Lock nuts (4)
• Tubing with lock washers and nuts
• Lamp socket
• Hot glue

The meter was acquired from a friend that works for an agency that was disposing of non-functional meters. You may also be able to pick one up at a surplus store, an auction or through a catalog. I bought a lamp at the thrift store to get the lamp tubing I needed.

Optional materials for LED illumination of the dial:

• LED
• Wires
• Batteries (3 volts in total)
• Scrap metal (I used a penny)
• Plastic container (I used a pill bottle)
• 2 rubber bands (Not pictured)
• A rotary switch (On/off not reostat)

Comments

[flat4photo]

Hi I made one of these lamps and i have lit the dial with and LED and made the needle move to around the 3.5r area and powered it all off the mains.

This is what I did to do it.

I wired in the lamp as per normal for 240v (im in the UK) but i used a 1megaohm rotary switch to turn it on and off using the original range knob.

I also ran off the 240v side a 240v - 12v transformer that i robbed out of an old aquarium pump or something. i opened the unit up and soldered the 240v main feed onto the input side of the transformer. this gave me 12v out the other side.

off of this 12v supply i now wired in a 560k resistor (i think - its covered by heat shrink now) followed by an LED - this illuminated the dial.

Also off of this 12v side I wired in a variable trimpot , sorry i just experimented and found one that worked out of my box of bits) that dropped the voltage and meant i could adjust the needle to fall where i wanted. i just set it to around 3.5r/hr.

to power the meter i simply wired positive up to the +ve side and negative to the -ve side. 12v was to much and pegged it out right off the dial so hence i used a pot.

By doing all this i can switch the lamp on with the original range switch, which turns on the bulb, lights up the LED dial and moves the needle up the scale.

With hindsight i would prob use a few LEDs as the dial isnt that bright, but other than that im happy.

Here is a really crud wiring diagram to explain it, dont flame me as i have no electronics background i just fiddle and made this diagram purely to illustrate this point. If its wrong or i have badly mucked up please tell me!!

i have labelled it as i wasnt sure of all the symbols....

see attached, and also this photo on flickr which illustrates the dial

[flat4photo]

oops flickr link

http://www.flickr.com/photos/flat4/5955640823/in/photostream/

[RadBear]

Just a quick note: If you're meter comes in the original civil defense cardboard box, be very careful of the staples that reinforce the corners. They are razor sharp. I have an inch long cut being held shut with three sutures to prove it.

[D3V1LSN3V3RCRY]

quick question: i have everything i need for this EXCEPT the actual geiger counter/survey meter. where can i find this model of survey meter to either purchase/get from donation?

[RadBear]

Several folks were able to find them on E-Bay. There are also several places that sell surplus Civil Defense Meters. Try Googling "Civil Defense Meter" or CDV-715 and you may find some that way.

[mbear]

Sweet! I didn't know you added the LED lights. Awesome. Now you just need to put it on a timer so it can act as a night light for you when you're wandering through your house in the middle of the night.

[Codswallop]

This is such a cool idea, I'm dying to try it! One question, though: How heavy is the empty case? Specifically, is it bottom-heavy enough not to topple over at the slightest provocation once you put a shade on the thing? Also, I'm wondering about that shade. What sort of thing could I cobble together that would suit the project? Maybe something with the CD emblem printed on it? A "Duck and Cover" instructional poster from the '50's? Anybody else have any ideas?

[RadBear]

It's not all that heavy but once I got the legs level it is very stable. I've adjusted the shade with nary a wobble in sight.

[Derin]

Can you post a pic of the full schematic that was in the box?

[justanassembler]

if anyone is interested I have a quantity of these meters available for purchase. im in minneapolis, but will ship for the cost of postage

[CybergothiChe]

could you ship one to Australia?

[justanassembler]

unfortunately, these have all been sold--thanks to all who inquired

[static]

That may depend if the US government has any restrictions on exporting such instruments. I wouldn't have a clue if there is or not, if there is Australia may be an exemption. In any event sending a gutted cabinet may get around any restrictions that exists. I suppose someone up to no good would send it one piece at a time. Like J. Cash's caddy. :)

[sindaear]

I would be interested depending on the cost.

[ungood]

If you have any more, I'd be interested too. Moving into a new home and need to make some cool furniture for it :)

[sweasel]

I'd like one if any are left

[downeasta]

I would be very interested. I plan to use a modified LED flickering "Tea candle" to provide both the light and some meter movement. Have thought about adding a speaker for a little ticking as well. Might as well go for it! Please let me know how much & how to pay. Thanks.

[Bonnonon]

If you figure out how to get the meter to move and have a small ticking sound could you let me know?

[conrad2468]

how much? and do you have any "sensitive" ones i accidentlly bought one of these and it read that my house was incredibly irradiated!!!! (figures!!! i live in wyoming) anyway how much do the ones with probes cost? (if you have any)

[Xellers]

Are you sure it was calibrated right?

[Bonnonon]

I would love one. Please contact me! :)

[crazycommanche=US=]

what does ship with the cost of postage mean like s and h or like a stamp

[TheOneTrueStickman]

A stamp only works for envelopes 1oz or less. The cost of postage for something this size would be multiple stamps, probably around $5 or so. (Wild guess.)

http://www.usps.com/prices/first-class-mail-prices.htm

[JSUTHERLAND8]

I LIKE IT....Cool look with blue or green meter light. Will have to keep my eyes open for an old survey meter up in Canada. Built lots of them back in the 80's. Nice (green type) recycling project, hard to reuse some old electronics stuff. May convert meter to read AC line voltage, with compressed scale 90-130 volts. Thanks; John8

[mg0930mg]

Very Nice. High-five. >.O

[gmjhowe]

Great work! it makes for a perfect lamp base. I would be tempted to either colour in the bulb green, or make a slim green lampshade for it.

[mg0930mg]

That's what I was thinking too. >.O

[Arx]

Cerenkov radiation is actually blue, so that might be a more appropriate colour.

[captain Jack]

awww, booo you destroyed the geiger Counter!

[RadBear]

Don't feel bad it was a piece of junk anyway. That's why it was free. And it wasn't destroyed. It was mercifully euthanized...and then stuffed and mounted.

[The Lightning Stalker]

It's just a CD-V 715 ionization chamber detector. They won't even give a reading unless you're being cooked by dangerous levels of radiation. So they're prettymuch useless. Now if he mutilated a CD-V 700 or an Eberline, that would be unforgivable.

[conrad2468]

i was wondering why my new detector was so insensitive!!!

[Bonnonon]

Very make shift, but it works :) I wonder if their is anyway to run the led off of the cord and the needle as well? Have you inquired anywhere about this? Maybe the community can help.

[TheOneTrueStickman]

The LEDs would be pretty simple - dig up a 5V phone charger/wall wart and run the LEDs from that. I recommend the really small warts that are rated 5v at 1A - they're switching supplies, not the normal (less efficient) transformer. A regular inductive wart would work, too, though. Put the switch for it on the line side so you're not wasting power. The needle could probably be adapted fairly easily as well, it's probably a normal micro-ammeter with a different scale on it. Google should be able to help more on actually wiring it up, I'm a little rusty on my meter innards. The meter requires a DC current source, so you will need a rectifier (if attaching to the AC line) and a voltage divider/resistor network of some sort to convert your voltage into a current within the range of the meter.

[Bonnonon]

Thanks for the answer. I will try to do some searching and see what I come up with.

[RadBear]

Yeah it is definately an ugly step child of battery holders. Hopefully the people who know what they're doing won't be too disgusted. :) I'm sure there would be folks willing to help but I haven't asked around about it yet.

[Bonnonon]

Thanks for the fast response. :) Good Luck.!

[Bonnonon]

Oh yeah I am planning on making mine into a touch lamp. :) Yes, I know I cannot use environment friendly light bulbs... BUT it will be amazing. It would be neat if someone touched it and than the needle moved. HAHA.

[Arx]

You can get CFLs made for 3 way lamps. They're quite common. Just look for ones with 3 wattages listed. :) LEDs could work too, but will be a lot more $ and much more complicated to power.

[brendanjcrlsn]

or if someone got within 6 inches of it and it moved the needle. That would be funny