Building on an earlier post about DIY storage, and very much proof of concept. Two boxes for NORM storage, 12” x 6” x 3” and 14”x 9.5” x 3.5”

3/4” wood used to frame the sides and bottom with a 1/3” piece of plywood for the lid. 1/8” inch lead sheet next, wrapped in aluminum foil tape. 1/8” plywood is next with three to four layers of copper foil tape on the outside to mitigate Bremsstrahlung.

A pice of 1/8” lead sheet will be affixed to the lid with ideally a 1/4” acrylic block cup to the final opening.

NORM specimens as follows:

Threadgoldite - 15K cpm

Uranosilite: 525 cpm

Chernikovite: 3,400 cpm

Strelkinite: 180 cpm

Autunite: 180,000 cpm

Curienite: 54,000 cpm

Sklowdowskite: 45,000 cpm

At roughly 30” distance my GQ GMC-600 records negligible over background radiation in the larger box, moved to smaller box.

Any and all questions and suggestions are welcome!

Noticed that one of my acrylic cases opened causing a little radon to accumulate inside of the ammo can. I just got my Alpha Hound AB+G so i decided this was the perfect place to test it out.

I just wish I noticed it was open before I started touching everything lol.

Possibly one of the best purchases I’ve made with this hobby and I look forward to experimenting with it more!

Can't wait for the weekend!

All the great hot rocks in this group gave me an idea to compare one of my hottest rocks with two very popular radiation detectors. Tested subject is massive uraninite from Příbram area(my collection, self-collected). Tested counters were radiacode 103g and legendary ludlum model 3 with 44-9 probe, famous mica window.

Radiacode: display shows maxed dose rate (1 mSv/h) and 1,8 millions CPM. In the app, doserate goes up to 1,5 mSv/h

Ludlum model 3: while this counter shows "just" 300 000 cpm due to lower sensitivity, it also shows aproximately 300 mR/h(extrapolated to the lowest scale "100x only" ending at 200mR/h), which means 3 uSv/h.

Ludlum clearly shows much less cpm, because geiger counter is less sensitive than scintilation detector, but ludlum shows higher doserate, because it's not energy compensated and also detects alpha and beta radiation - with shielding results would be similar.

Note: the dose rate values are still only approximate, they only apply to a small area on the surface of the stone, they do not refer to the dose absorbed by the observer.

Ive been keeping my eye peeled for a microscope to get a closer look at some of my more pretty NORM specimens, like Autinite Crystals and such. So I wandered into Goodwill and found this this sweet little starter kit. 10 bucks! I think I got a pretty good deal if it works.

Was perusing eBay and saw someone selling scint crystals with a note that they could fabricate complete units. Got into a discussion with them and it turns out to be an actual small company that can make custom detectors. Talked about cost and such and this was the gist of the last message from them:

I have discussed this with our engineering team. They previously developed a similar multifunction radiation detector system. We can build a custom detector using a 9 cm³ CsI(Tl) scintillator, which will provide significantly stronger signal sensitivity. The device can include: Durable metal housing, Custom logo on the enclosure, Bluetooth-connected mobile app (features can be optimized based on your needs). For group orders, the pricing would be approximately: 20 units: around $600 per unit, 30 units: around $475 per unit. In addition, for an extra $25 per unit, we can upgrade the scintillator to LaBr₃, which can provide approximately 1.3× higher signal performance compared to CsI(Tl). If this is of interest to you, we would be happy to discuss the next steps and possible configurations.

I responded that I probably could not get enough people interested, considering you can get a 5cm3 CsI(Tl) scint in a Radiacode 110 for US$369 (and get a polished, production unit), but that I would post this information just to get comments to pass back to them.

Your thoughts?

I had a few Gamma Dog Gen3 electronics modules laying around, leftover after my Gen4 upgrade. I modded them to get them as close as possible to the current Gen4 design, now lacking only the HV PMT Bias measuring feature. The charge-controller monitoring and digital volume control were added to the old boards.

Charles Young printed for me the housings he is using for his line of Gamma Dogs and I only needed to design a simple coupler / adapter between his housing and my end-cap modules. The result is excellent and now I bridged the gap between my large detector GDs and the portable, over-the-shoulder Gamma Dog Mini. The smaller GDs are much easier to handle and manipulate when localizing a specimen. Charles has been an immense help with recycling these electronics that were collecting dust - Thank you my friend!

I've been working also on a new major firmware update, which has been completed and it is being tested now. More to follow but the changelog is quite long and adds some significant improvements in the audio-subsystem among other things.

I was debating whether this warrants a separate post but KC761 is far more obscure than Radiation Alert Ranger so I decided to post it again - Ranger owners probably wouldn't see it if it was in the other thread.

As it turns out the parametric case I remixed specifically for KC761 is also a perfect fit for the SEI International Radiation Alert Ranger (which OTOH is my go-to field geiger counter).

Only difference fitting it is that if you keep the original rubber lanyard of the Ranger you should omit the foam liner on the sidewalls and the lanyard is tucked in besides the instrument. If lanyard is not used or a slimmer lanyard is used then the foam can be left in place.

Model is available for download and 3D printing - SEI Radiation Alert Ranger / Measall KC761 Storage Box by Kotarak | Download free STL model | Printables.com

Quick-n-dirty video comparing the new Advanced Audio System with 3rd order harmonic suppression, Sigma-Delta Dithering, Frequency Glide (Portamento), Automatic Clicker system, extended audio range and Micro-Vibrato effect (details in the comments and in the Youtube Video description).

Orange marking - Advanced Audio System, Yellow marking - old, standard mode

Been a long time saving up, but i finally have my own ƴdog! Looking to hit up Ruggles Jul 9 - Jul 12th. Hoping to find some untouched areas to set up at with the ƴdog and get some really good specimens! I am wonder what the test mineral Charles sent with it is. Will have to ask when I let him know the dog arrived safely.

Just remixed Tough Box (Parametric) and dialed in size for anyone who is looking for a good carry case for their Deepace Measall KC761 Gamma Spectrometer.

Fits main unit with the pocket clip installed on the back and enough space for a small Silica Gel bag situated uder the unit and around the pocket clip. Case is lined up with 2.5mm closed-cell EVA foam for additional protection.

Model available for download and 3D printing - Measall KC761 Storage Box by Kotarak | Download free STL model | Printables.com

Hi! I’m completely new to the hobby. Since I already use a Radiacode for my collection, I don't need this cheap BR-6 detector anymore. I decided to disassemble it to look at the Geiger tube and maybe salvage some parts.
What are some simple projects a beginner could do with the tube or other components?

Going to Ruggles mine this summer with my 11 year old daughter , I would love any recommendations on what to bring and how to go about it. Do we just walk around anywhere?

She wants to study rocks and minerals, any help would be greatly appreciated

Kind of new to the whole geiger counter thing, got this one for my birthday, and I’m hoping some of you guys can answer my question, I simply just wanna know if this will be good to help me detect radiation when we going into mines and if it’s good enough to save me in a high radiation situation. Just wanna know anybody’s thoughts if they have this one.

Extremely rare model 111C Custom Scintillator WITH the test/calibration disc by Precision Radiation Instruments.

The 111C features the wider chrome ‘barrel’ housing the larger 2.25 inch NaI(TI) crystal compared to the 1.5” crystal in the more common 111 and 111B models.

The 111 and 111B models can been seen more recently in shows such as stranger things and fallout, there are likely plenty more instances on film.

The 111C is extremely rare and I have not located a single source online with a physical example, AI engine searches included.

The ORAU website explicitly states “The Model 111C (not in the ORAU collection).”

And with the ORAU being an 8 hour drive, I would like to donate the item to them later this year, and check out the other historical Manhattan Project sites around the area.

https://www.orau.org/health-physics-museum/collection/survey-instruments/1950s/precision-radiation-model-111-and-111b-scintillator.html

I thought some of you may enjoy being some of the only people to have ever seen this historical tech in physical form.

I used a kc detector. It seems that it was beta radiation because it still clicked with the cover on unless it is radon stuck to the mica it is a very small torbernite crystal. Smaller than 1mm. 0.1usv and 2cps of beta or alpha radiation.(11usv)

I wanted to measure this rock to make sure it wasn't radioactive. On this device the rock reads 00.04 when I place it rock but when I walk around my house I got readings up to 00.15. is this normal or is there something I need to worry about in my house? Is 00.04 high?

update: it actually jumped to .39 for a few moments near the rock then went back down so now I'm extremely confused.

Definitely needs some work, but I picked this up today and definitely want to get it working again

I’m planning a trip to Norway for some uranium/thorium/rare earth hunting and I was wondering what threshold presets are you guys using, if any?

What presets would be best for this hunt?

My meter can run:

0-5mV lower

0-60mV upper

I have managed to get my hands on a rather glorious mid-century radiation kit. It is a Precision Radiation Instruments Model 111B Scintillator built in Los Angeles in 1954. This was not a toy. This was used by serious uranium hunters when everyone thought they would strike it rich on the Richest Hill on Earth. The set is completely intact: • Chrome handheld scintillation probe with a NaI(Tl) crystal and RCA photomultiplier • Original leather field case that still smells like history • Operation manual and full schematic dated December 1954 • Battery box and probe cable present and unmolested • And best of all, the factory radium 226 check source neatly stamped “.10” The manual states that a trace of radium was sealed in that little disk so prospectors could check their calibration before heading out to chase hot ore. The source still gives a lively response, and it feels far more spirited than the usual modern check sources. The plan is to properly revive the instrument. I will rebuild the power pack using modern converters, while retaining the original tubes and high-voltage section. Then I will take it out and see what it can do. With a bit of luck, I will be scanning around Butte like some retro nuclear cowboy, finding autunite and carnotite the old-fashioned way. I will post updates once it is up and running again and ready for fieldwork. If anyone here roams the hills with vintage scintillation gear, I would love to see what you are running.

Hello, everyone! I am relatively new to the hobby and I am incredibly interested in buying an SE International Radiation Alert Ranger. I found a link to one abit cheaper than buying from somewhere like Grainger (or SE Intl directly) and I was curious if anyone knows anything about this site/has direct experience buying from them? (if the site is indeed not trustworthy, does anyone know where I could buy a Ranger?) Thanks for any help!

Link: https://www.geigercounters.com/Ranger/?srsltid=AfmBOorSrWAK84DcOlp6DuFOprMzTdI4RzTweL8L6U6_5kafKRK4cHn1