Geiger Counters, Radiation, Electronics, Projects and Other Random Stuff

Archived from radmon.org - originally posted 12/06/2023 I was asked by Gissio to try and download the original firmware from my HFS-P3, so I tried. Alas, no joy so far. ☹️ Under the battery (stuck down with sticky tape) is a pin header. Probably designed to have a pogo pin connector connect to it as there is no room to solder on an actual pin header. I just soldered wires to it directly. I managed to work out the pins by tracing the circuit, but I had to use my microscope as the connections on the MCU really are that small! I took photos of both sides and flipped one then overlaied one over

Archived from radmon.org - originally posted 09/03/2023 A while ago I saw a video (below) where the creator had purchased several 'Negative Ion Energy' products that actually contain radioactive Thorium. Most of these products are wearable items and some other 'Nume' cards, or whatever they are. At the time I searched for these but seems they had all been pulled form the stockists shelves. Then I saw a more recent video by the same creator and searched again, and lo and behold, the same products are stocked up again and readily for sale - to unsuspecting people that may possibly actually wear

Archived from radmon.org - originally posted 25/02/2023 A cheap and easy way to change a blue LCD or OLED display to yellow/amber using Kapton tape. I don't like blue displays. I never have done. I have always found them to be harsh on the eyes, especially in dark environments. I also find them more difficult to read than green or yellow displays. Blue is a colour that is rarely found in nature. It really was a colour that was/is quite unnatural to the eyes until recent times. It reduces melatonin release into the body and can affect sleep. I discovered some years back that Kapton tape can

Archived from radmon.org - originally posted 29/01/2023 My J305βγ tube is very light sensitive so I made a quick video demonstrating this. I shine daylight (on a miserable cloudy grey day) on the tube at first, then a 365nm UV flashlight and finish off with daylight again. The effects seem to work only at the anode end and not at the cathode end. Doing a little research I found that the light sensitivity of GM tubes only occurs in glass walled tubes that have an external cathode. The specifications show this about the tube wall: Tin oxide Cathode, Coaxial cylindrical thin shell structure

Archived from radmon.org - originally posted 28/01/2023 A member (of radmon.org) asked me if the Gamma Scout would/could work with radmon.org using the USB and software the counter came with. The answer to that is a simple, no, but it could be down with a quick hack. Simply add a couple of wires and connect them straight to an ESP8266 or similar MCU. This guide only covers the 'Alert' model. There may be differences with other Gamma Scout models. Here is how: Open up the Gamma Scout and locate the small transistor at the top left of the board, right above the pin header. There we are going to

Archived from radmon.org - originally posted 23/12/2022 Here are some pictures and details about the SI-8b (СИ8Б) Pancake Geiger Muller tube. The adhesive failed between the tube and the Bakelite rear case on my tube, so it would be rude not to take it apart for a look! From what I understand this tube is designed for soft beta detection, but is also capable of alpha, hard beta and gamma, although calibration would center on soft beta particles. I did however read this from a website: 'This Geiger-Mueller tube is only sensitive to β and γ radiation. The calibration is only correct for the γ

Archived from radmon.org - originally posted 12/12/2022 ** Note: This is for submission of CPM readings to radmon.org. This was working at the time of writing but updates to libraries may cause issues. Here is some Arduino code for the Arduino Uno, Mega2560 and Pro Mini with WizNet W5100 ethernet shield. This is bare-bones code only. It does only these things: receives pulses on pin 2 (Uno, Mega & Pro Mini), calculates CPM and submits it to Radmon.org (via ethernet shield) every 60 seconds. It has a little debugging that can print to serial and I have also added CPM print to serial (much

Archived from radmon.org - originally posted 11/12/2022 I have seen these kicking around the usual suspects (Ebay, Amazon, Aliexpress etc.) for a little while now and after watching (a not very informative YouTube video) I decided to get one and see just what it is and is it any good. TLDR; You get what you pay for. I paid about £32 for this from Aliexpress.com but have seen them for as little as £25 on Aliexpress.com and as high as £60 on Ebay and Amazon. The unit is very small and packs a tiny 150mAh LiPo cell, 48mm x 7mm (external dimensions) HH614 GM Tube, tiny OLED screen, a massive

Archived from radmon.org - originally posted 13/11/2022 I recently obtained some radioactive rocks from an eBay seller for a low low price of..... £1 each! 😆 Plus £8 shipping each... 🫤 I didn't realise how much there really was until I weighed them, and they come in at a whopping 14.5 lbs, or 6.6 kg! 😯 I believe they have come from the South Terras Uranium Mine in Cornwall. The mine was closed back in 1930 and apparently the mine itself is inaccessible since then although someone gained access and took some pictures of the mine itself. It is still very radioactive now. Some of the buildings

Archived from radmon.org - originally posted 20/02/2022 ** Note: This is for submission of CPM readings to radmon.org. Here is some Arduino code for the ESP8266 written and tested on a Wemos D1 Mini. This is bare-bones code only. It does only these things: receives pulses on GPIO 13 (physical pin D7 on Wemos D1 Mini), calculates CPM and submits it to Radmon.org (via WiFi) every 60 seconds. It has a little debugging that can print to serial, flashes the internal LED when an interrupt event is detected and I have also added CPM print to serial (much like the NetIO GC-10) that can be used with

Archived from radmon.org - originally posted 16/02/2022 I was repairing an old Russian DP-5V counter yesterday and noticed an unusual neon/orange flashing glow coming from the probe PCB that I have never seen before, so decided to investigate. It is caused by two thyratrons on the board, flashing away with the clicks of the counter. They are similar to modern thyristors in their function. These thyratrons are filled with neon gas, hence their orange glow. This is from wikipedia: https://en.wikipedia.org/wiki/Thyratron Conductivity of a thyratron remains low as long as the control grid is

Archived from radmon.org - originally posted 13/02/2022 Following on from Pt.1 - Here are some pictures of the battery compartment. You can see the terminals at the bottom pivot in the middle like a seesaw, also with one battery inserted and then with two. I couldn't resist and took out the tube to have a look at it. It is rather large, pictured below next to a STS-5 tube (SBM-20 equivalent.) ↑ Seesaw battery terminals with pivot at the center. ↑ ↑ One battery inserted. ↑ ↑ Two batteries inserted. The cap has a large shaft that pushes down on the positive terminal, the battery is pressed down

Archived from radmon.org - originally posted 13/02/2022 This is one of my latest Geiger counters and it is in fantastic condition. To say this is probably more than 60 years old, it has really faired well. It wasn't working when I got it as one of the battery terminals had some corrosion to it. After a quick but very awkward clean up of the terminal it came to life. What really attracted me to this, besides it's condition, is the fact the meter is in CPS (counts per second.) I thought it unusual for a small counter of this era to be in CPS. Being CPS would mean it would be sensitive, which it

Archived from radmon.org - originally posted 06/02/2022 I have translated the manual with the help of a couple of internet AI translators. Attached below you will find a couple of PDFs of the original Russian manual and an English translation of the manual, also the text of the manual in .txt format. The PDFs quality isn't great as the images weren't great but they work. The text version is probably easier to read. A couple of things about operation that I was puzzled about were the mains/missing psu and missing battery. From reading the manual I'm assuming that this was in fact a "Lux"

Archived from radmon.org - originally posted 05/02/2022 I have managed to power this up and it does work! 😊 I have also started reverse engineering it a little. I removed the two (brass?) strips and replaced them with wires so I can flatten the board out properly. The two strips were connecting the ground and VCC on the boards together. I haven't yet translated the manual, but I will in due time as I can't find a single thing about this counter on the internet at all and the info may be of use to others' too. In all it seems like a very basic counter with a quirky display. If I knew what the

Archived from radmon.org - originally posted 01/02/2022 I found this on ebay priced at £12.52 delivered and couldn't resist at that price so I bought one for shits and giggles! Probably the most bizarre counter I have bought yet. (Apologies for the camera focus - new camera, very complicated... 😯 ) I haven't powered it on yet as I have no idea what battery it should be, if it should be a battery at all. It has US mains plug pins on one end but there is nothing wired to it, nor is there a battery cover. The only way to put a battery in is to disassemble the unit, which is rather cumbersome. It

Archived from radmon.org - originally posted 20/12/2021 [Updated: 22/12/2021] Its the first day of holidays and I'm bored already.... So I cooked up a neat wifi/wemos d1 mini/arduino/LED display for displaying a station's current CPM. It works by simply connecting to one's Wi-Fi and then goes to the URL, pulls the data, strips the first space and everything afterwards then converts what is left to a float (the CPM count from the start of the string) and displays it. The bar graph LEDs are mapped from 0 to 100 CPM at full scale deflection, but the 7 segment display will display up to 999.9

Archived from radmon.org - originally posted 19/12/2021 Whilst looking around the internet I found a trove of old declassified CIA documents. Among these were one called 'Chernobyl Nuclear Power Plant Accident CIA, Department of Defense, Department of Energy, Congressional, GAO, and Foreign Press Monitoring Files' that goes into some detail about the accident from the perspective of the authorities. There was originally 4010 pages and sadly this has been shaved down to a mere 224 pages in the released document. An excerpt of this document: THE ACCIDENT According to reports filed with

Archived from radmon.org - originally posted 05/12/2021 Something I really dislike is planned obsolescence, and closely 2nd to that, where things are not user serviceable and have to be returned to the manufacturer for minor things such as battery replacement. I'm a large advocate of 'right to repair'. The battery in the Gamma Scout is a 10 year, 3.6v Lithium battery soldered directly onto the board. Gamma Scout (at last check some time ago) wanted 40 Euro plus shipping one way to Germany to replace the battery. Pfft! The original battery is about £20 all in for a replacement, but I decided

Archived from radmon.org - originally posted 04/12/2021 Well, I managed to destroy my second SBT-10A. The first destroyed itself as far as I am concerned as I took it out of it's box one day, and it was toast - post here . This one was my fault. I dropped a polarizing filter on the mica window (only from about 4cm) but it hit it and went with a proper loud bang, right in my face and showered my microscope and desk with bits of mica, then the black bits on the inside of the mica just turned to a yellow schmoo in the air atmosphere. It would have been a nice experiment had I actually planned