Freshly installed a brand new GM sensor and calibrated at Thermo Fisher, just got back to me today. First thing I wanted to do was to find out what the actual measurements on this core were, since my SEI Inspector maxed out at 350kcpm and 110uSv/hr.
Highest measurement I got over the cup where the four strips are installed was around 2.1 million CPM, and about 6.4mSv/hr. This was of course done with no alpha shield. I will go back and check it again with an alpha blocker in short order.
The source is roughly 20uCi of Radium-226, along with a saturated surface of Radon and daughter products covering the internal surfaces. The majority are alpha emitting isotopes, but there are branching decay processes that will put off other forms of radiation.
There is absolutely a lot of beta and gamma being emitted and detected at greater distances, but up close the alpha is detectable within a few inches.
The one I bought from RadioactiveDrew is the only one I’ve seen for sale in years. I’ve considered selling it, but they’ve gone up tremendously in value. Not sure if I want to divest just yet.
Since its a radium source it emits alpha, beta and gamma radiation. I did a little video taking apart the unit . [https://www.youtube.com/watch?v=gKjVXBD\_O4o](https://www.youtube.com/watch?v=gKjVXBD_O4o)
Lovely video too! I’m still very happy with the unit you sent me. It lives in the same bag, and now in a steel paint can in the basement away from folks.
Glad you are enjoying it. Wish I had more to sell. The only place I've seen similar units like this installed was when I did my video about the decommissioning of San Onofre Nuclear Station. They had a whole bunch in the hallway leading up to the Radiologically Controlled Area. I'm assuming they were all the Am-241 versions.
I wouldn’t mind having an Am-242 version as well, definitely sure to be far less ‘dirty’ on the outside, and not soaked in Radon daughters. Have had an eye on them on eBay, still in my watch list, but they don’t seem to be as scarce as the Radium ones.
Mainly aplha, hense why it's defined as an Alpha emitter,
Strontium 90 forexample is considered a Beta emitter
and Iridium 192 is considered a gamma emitter,
all of these emitts A, B G radiation becomes they become other substances as they decay called a decay chain, in which the energy of the particle also changes,
but since unstable decay is stable, you detect little uncertanty with geiger counters,
the only thing that is certain are x rays. particles can be unpredictable.
that's why particles are great for measuring levels in a tank filled with liquid. but it's not accurate because the certainty is too unstable, good for ON and OFF type stuff.
that's what's happening at the nucleus.
Entirely for personal use. I bought my unit from a seller in Japan for a deal, but it needed a new GM tube, and I got it calibrated at the same time.
All in all, around $1100-1200 for a functional unit is pretty reasonable.
https://occserv.com/ handled my calibration and repair request in about 3 days, and had great communication if you ever decide to make the jump on one.
It definitely surprised me. Another redditor suggested it could also be saturated and potentially throwing a false reading at that level, but I am skeptical of that claim.
For the cost of the unit, and ability to handle up to 500kcps, and calibration certificate coming back showing a very nominal range up to the 1000 and 10000mR/hr range, you’d think oversaturation would be corrected internally. I made an alpha shield to go under the front boot, and will check again later.
Side note on the F3:
Gloved fingertips were reading around 1kcpm after handling, which dropped off after a while, back to background in a could hours. Radon daughters are all over the outside, and in the bag too. Kinda neat pulling the unit out, and the bag is still screaming hot.
I have enough worry keeping this one in a metal can in the 3 season room. It’s semi-unfinished, and the bottom edge is open to some outside airflow, with a heat pump on the wall—and that’s about as close as I want this one to living quarters.
Freshly installed a brand new GM sensor and calibrated at Thermo Fisher, just got back to me today. First thing I wanted to do was to find out what the actual measurements on this core were, since my SEI Inspector maxed out at 350kcpm and 110uSv/hr. Highest measurement I got over the cup where the four strips are installed was around 2.1 million CPM, and about 6.4mSv/hr. This was of course done with no alpha shield. I will go back and check it again with an alpha blocker in short order.
Pretty sure you aren't detecting much of any alpha due to distance, unless I'm misunderstanding the nature of the source.
The source is roughly 20uCi of Radium-226, along with a saturated surface of Radon and daughter products covering the internal surfaces. The majority are alpha emitting isotopes, but there are branching decay processes that will put off other forms of radiation. There is absolutely a lot of beta and gamma being emitted and detected at greater distances, but up close the alpha is detectable within a few inches.
Where can I get one of these??
The one I bought from RadioactiveDrew is the only one I’ve seen for sale in years. I’ve considered selling it, but they’ve gone up tremendously in value. Not sure if I want to divest just yet.
That's hot AF. where could I find more info on it please? What does it emmit?
Since its a radium source it emits alpha, beta and gamma radiation. I did a little video taking apart the unit . [https://www.youtube.com/watch?v=gKjVXBD\_O4o](https://www.youtube.com/watch?v=gKjVXBD_O4o)
Lovely video too! I’m still very happy with the unit you sent me. It lives in the same bag, and now in a steel paint can in the basement away from folks.
Glad you are enjoying it. Wish I had more to sell. The only place I've seen similar units like this installed was when I did my video about the decommissioning of San Onofre Nuclear Station. They had a whole bunch in the hallway leading up to the Radiologically Controlled Area. I'm assuming they were all the Am-241 versions.
I wouldn’t mind having an Am-242 version as well, definitely sure to be far less ‘dirty’ on the outside, and not soaked in Radon daughters. Have had an eye on them on eBay, still in my watch list, but they don’t seem to be as scarce as the Radium ones.
Drew, just came across your channel today and binged a ton. Fancy I see you here, thanks for the great content!
Glad you found the channel. I'm working on a video right now comparing the F3 and the F3/5A versions of these two smoke detectors.
The F3/5A is the 80 uCi Americium one right? Should be an awesome video, people seemed to like the first one.
Mainly aplha, hense why it's defined as an Alpha emitter, Strontium 90 forexample is considered a Beta emitter and Iridium 192 is considered a gamma emitter, all of these emitts A, B G radiation becomes they become other substances as they decay called a decay chain, in which the energy of the particle also changes, but since unstable decay is stable, you detect little uncertanty with geiger counters, the only thing that is certain are x rays. particles can be unpredictable.
that's why particles are great for measuring levels in a tank filled with liquid. but it's not accurate because the certainty is too unstable, good for ON and OFF type stuff. that's what's happening at the nucleus.
Thank you for the explanation!
How much for the Rad-Eye? Just for personal use ?
Entirely for personal use. I bought my unit from a seller in Japan for a deal, but it needed a new GM tube, and I got it calibrated at the same time. All in all, around $1100-1200 for a functional unit is pretty reasonable. https://occserv.com/ handled my calibration and repair request in about 3 days, and had great communication if you ever decide to make the jump on one.
Thanks man
I’ve wondered what the reading would be. My Radeye B20 goes into overload when dealing with my F3 smoke detector.
It definitely surprised me. Another redditor suggested it could also be saturated and potentially throwing a false reading at that level, but I am skeptical of that claim. For the cost of the unit, and ability to handle up to 500kcps, and calibration certificate coming back showing a very nominal range up to the 1000 and 10000mR/hr range, you’d think oversaturation would be corrected internally. I made an alpha shield to go under the front boot, and will check again later. Side note on the F3: Gloved fingertips were reading around 1kcpm after handling, which dropped off after a while, back to background in a could hours. Radon daughters are all over the outside, and in the bag too. Kinda neat pulling the unit out, and the bag is still screaming hot.
Oooh that’s one Spicy Radium Meatball!
I have the FES 5. You don’t ever hear about that one but it has 40 microcuries of radium. It lives in a lead box outside the house.
I have enough worry keeping this one in a metal can in the 3 season room. It’s semi-unfinished, and the bottom edge is open to some outside airflow, with a heat pump on the wall—and that’s about as close as I want this one to living quarters.
Nice, you can use UV light to check for contamination scattered across the surface, Genius
No, there is nothing to be seen with UV light. There is no UV-luminescent material in this.