What did you buy today? Post your latest purchase!

[PlainName]

Got a tritium keyfob which has been in my pocket for at least a decade. Excellent toy - drop your keys in the dark and you can find them easily without having to have slipped back in time to turn on the keyfob torch just before

Last time I looked my leg was still there, not withered away, and no incriminating moles or other marks.

[paulca]

I have a brand new Tritium-Phosphor one.  I also bought my 6yo daughter a pink one.  I had one from "Think Geek" from way back in 2006, but it was pretty dead last time I say it.

apparently tritium lights make some gamma because of breaking radiation

Bremsstrahlung sic Braking Radiation.  When an electron is forced to change momentum (direction or velocity) (aka braking) it emits a photon depending on just how fast your electron is going that can be xray or gamma.

The tritium emits low energy beta.  These excite the coating to release light.  Those that get through collide with the glass.  Colliding with the glass electron field at some fraction of C, and some N thousand electron volts, causes a gamma emission.

It's demo'd and explained here nicely:


I have measured mine with the GMC-500+ Gieger-Muller detector.  It also never seen any beta, but it did see the Bremsstranlung radition.  However, I had to leave the keyring directly under the detector for 12 hours with 12 hours either side just to see the very, very slightly elevated portion.  It increased the count rate from about 18CPM to about 19CPM.

I have my background spectrum now, I will see if I can capture an hour with the keyring and we'll see if we can even see the key ring in the noise low keV noise.

[paulca]

After 30 minutes with the keyring it's "inconclusive".


Spectrum with green line as background.


Rates over 1 hour.  30min without and 30min with the keyring sitting on top of the detector.


Background with Isotope info shown for radon daughter products.


Background with isotope info shown for potassium 40.

[wkb]

K-40, you have been messing with bananas did you?

[paulca]

K-40, you have been messing with bananas did you?

You don't need to eat bananas.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4844139/

tldr; a milli-grey per decade from your own body K40.

[coppercone2]

and the little flashlight broke already. v 1.0 was better

[SiliconWizard]

Well you shouldn't have bought a Boeing flashlight.

[coppercone2]

how about radiation from those forever flashlights betalight? that should give a strong reading. the one for reading maps.

[jonpaul]

Dr Meter PH meter/probe, test food, water, soil PH. Accurate and esy to use. $25!

surface Humidity tester, pin and pinless to test for leaks and dryness etc. $25
(wood, Driwall, cement)

Enjoy,

Jon

[RAPo]

An Altai power-supply 13.8V DC/nominal 5A out.
I got it for Eu12.50, and checking it at home, there are even some extra non-advertised volts output is 15.5V DC;-)

[coppercone2]

here is some interesting math about the tritium keychain
https://www.gammaspectacular.com/phpBB3/viewtopic.php?t=889

the skin exposure divided by area is interesting to me. thats a big number

[exe]

I just bought a Harrison Laboratories 855B Power Supply. Out with the old homemade bridged variac. In with ..... an old ....

Oh, those are lovely! Pics by any chance?

[SiliconWizard]

here is some interesting math about the tritium keychain
https://www.gammaspectacular.com/phpBB3/viewtopic.php?t=889

the skin exposure divided by area is interesting to me. thats a big number

But if you lose a hand due to this, you always have your teeth to make up for it.

[BennoG]

Keithley 2400 broken as does not power on.
So hopefully it is a simple fix.
Will arrive next week 

Benno

[TopQuark]

PB Swiss Philips #2 

[gamalot]

I'm learning high school geometry again!  and German is so cool!

[BennoG]

This came up on ebay, I was looking for the 8 port version.
This is a step up from the 8 port.

Benno

[Edison]

A new addition, the audio analyzer from Dayton Audio DATS V3

[ClarenceMorse]

Waiting to see what other guys bought? Thanks for sharing.

[coppercone2]

I think I know why your readings are so low. Because your light is just in a acrylic or polycarbonate case. try one wrapped in stainless steel or the ones with a steel frame. It seems from research that the radiation interacts with stainless steel to make the gamma. Not sure if a 100% shield does it, but the experiences that look promising have a frame that looks to have circular edges around the tube.

[Zeyneb]

PB Swiss Philips #2

Good choice. Me too.
Earlier this week I had a PH2 screwdriver  broken at a junkyard. I decided I need to pay for a better screwdrivers. I used the Project Farm video to inform me about quality screwdrivers. Now I can immediately use them to put dashboard pieces back together on my car.

[gamalot]

Keithley 2510, there is a hole in the dilapidated front panel, but it still works fine.

Its main circuit board is different from the one in @Tin’s post many years ago. I will take some high-definition pictures later.

[armandine2]

I shall add a picture, all being well ... 

...just got an Urth MD-X adapter to connect an old secondhand Minolta wide angle lens to my Fuji X-Pro2.

...so the first one of these vintage lens and mount adapter acquisitions I made went ok.

This, second time ... the near mint old lens, with its missing red dot, I found getting it on the close fitting adapter more drawn out than I would've liked. And then when the pair were on the camera, no infinity focus .... in fact horrible focus.

...seems like there maybe some complicated fix ... oh well, a bit of a waste of money

... at least I got a filter with it - a Marumi mc +4 ?

... oh, that's a close up filter - umm don't think that's going help infinity focus.

    I would've been impressed if copilot knew that one.

edited to add a relevant mc+4 pic

[cosmicray]

An assortment of enameled wire sizes (22-32 AWG) from Remington Industries.

[armandine2]

...third lens came today - same model as the first, but this time a definite fault.

... very restricted travel on the focus ring, a few degrees of turn (from infinity to 1 metre).

described  as in good condition, 4 out 5.

...for those keeping score

England 10
Japan 7
France 0

...low score may get better - depending on recovering the cost. It was the most expensive of the three.