On 5G And The Fear Of Radiation

April 8, 2020 by 178 Comments

The world around us is a scary place, with a lot of visible and invisible dangers. Some of those invisible dangers are pretty obvious, such as that of an electrical shock from exposed wiring. Some are less obvious, for example the dangers of UV radiation to one’s skin and eyes commonly known, but also heavily underestimated by many until it’s too late. In the US alone, skin cancer ends up affecting about one in every five people.

Perhaps ironically, while the danger from something like UV radiation is often underestimated, other types of electromagnetic radiation are heavily overestimated. All too often, the distinction between what is and isn’t considered to be harmful appears to be made purely on basis of whether it is ‘natural’ radiation or not. The Sun is ‘natural’, ergo UV radiation cannot be harmful, but the EM radiation from a microwave or 5G wireless transceiver is human-made, and therefore harmful. This is, of course, backwards.

Rather than dismissing such irrational fears of radiation, let’s have a look at both the science behind radiation and the way humans classify ‘danger’, such as in the case of 5G cell towers. Continue reading “On 5G And The Fear Of Radiation” →

Tracking Cancer Treatment With An ESP8266-Based Radiation Sensor

January 25, 2020 by 22 Comments

Those of us who have not been in that position can only imagine the anguish of learning that your teenager has cancer. This happened to [Rob], whose child was diagnosed with papillary thyroid cancer. It’s a condition that can be treated with surgery followed by a course of radioactive iodine to kill any remaining cancer cells. During iodine treatment, the patient is radioactive enough that other people must maintain a distance of 3m from them, and as a learning exercise for both father and teen he created and refined the design of a portable wireless radioactivity monitor.

There are a variety of sensors for radiation monitoring including the well-known Geiger–Müller tube, but he settled on a PIN photodiode based sensor supplied by radiation-watch.org. This sensor is not at its most sensitive at the energy levels emitted by the iodine isotope used in the treatment, but the relatively high intensity of the radiation meant that enough would register for a useful reading to be taken. The sensor board he was mated to an ESP8266 module. [Rob] went through three iterations of the balance of the hardware before settling on a lithium-ion battery and a plastic case.

On the software side, the ESP connects to an MQTT server, from which a CSV file of data is derived. On a computer, the CSV data is collected and plotted to a graph. The data take during treatment clearly shows the reduction in radiation following the isotope’s half-life. The graph isn’t perfect though, there is a gap due to the second prototype’s batteries running flat

From his epilogue it appears that his son has recovered, and we wish them further good health. The details have been published in the hope that other young people facing the same trial might benefit from building their own radiation monitor.

Bent Electric Field Explains Antenna Radiation

October 2, 2019 by 15 Comments

We all use antennas for radios, cell phones, and WiFi. Understanding how they work, though, can take a lifetime of study. If you are rusty on the basic physics of why an antenna radiates, have a look at the very nice animations from [Learn Engineering] below.

The video starts with a little history. Then it talks about charges and the field around them. If the charge moves at a constant speed, it also has a constant electric field around it. However, if the charge accelerates or decelerates, the field has to change. But the field doesn’t change everywhere simultaneously.

Continue reading “Bent Electric Field Explains Antenna Radiation” →

Warwalking For Radiation

September 10, 2019 by 24 Comments

Can’t find a recently updated survey of radioactivity in your neighborhood? Try [Hunter Long]’s DIY scintillation counter warwalking rig. (Video also embedded below.) What looks like a paint can with a BNC cable leading to an unassuming grey box is actually a complete kit for radiation surveying.

Inside the metal paint can is a scintillation counter, which works by attaching something that produces light when struck by ionizing radiation on the end of a photomultiplier tube, to make even the faintest hits “visible”. And the BNC cable leads to a Raspberry Pi, touch screen, GPS, and the high-voltage converters needed to make the photomultiplier do its thing.

The result is a sensitive radiation detector that logs GPS coordinates and counts per second as [Hunter] takes it out for a stroll. Spoilers: he discovers that some local blacktop is a little bit radioactive, and even finds a real “hot spot”. Who knows what else is out there? With a rig like this, making a radiation map of your local environment is a literal walk in the park.

[Hunter] got his inspiration for the paint-can detector from this old build by [David Prutchi], which used a civil-defense Geiger counter as its source of high voltage. If you don’t have a CD Geiger detector lying around, [Alex Lungu]’s entry into the Hackaday Prize builds a scintillation detector from scratch.
Continue reading “Warwalking For Radiation” →

Global Radiation Montoring And Tracking Nuclear Disasters At Home

August 28, 2019 by 10 Comments

Many of us don’t think too much about radiation levels in our area, until a nuclear disaster hits and questions are raised. Radiation monitoring is an important undertaking, both from a public health perspective and as a way to monitor things like weapon development. So why is it done, how is it done, and what role can concerned citizens play in keeping an eye on things?

Continue reading “Global Radiation Montoring And Tracking Nuclear Disasters At Home” →

A PKE Meter That Actually Detects Radiation

July 24, 2019 by 5 Comments

Fans of Ghostbusters will remember the PKE meter, a winged handheld device capable of detecting supernatural activity. Precious little technical data on the device remains, leaving us unable to replicate its functionality. However, the flashing, spreading wings serve as a strong visual indicator of danger, and [mosivers] decided this would be perfect for a Geiger counter build.

An SBM20 Geiger tube serves as the detection device, hooked up to an Arduino Nano. An OLED display is used to display the numerical data to the user. The enclosure and folding wings are 3D printed, and fitted with 80s-style yellow LEDs as per the original movie prop.

The device is quite intuitive in its use – if the wings flare out and the lights are flashing faster, you’re detecting an increased level of radiation. In a very real sense, it makes using a Geiger counter much more straightforward for the inexperienced or the hearing impaired. Naturally, there’s also a buzzer generating the foreboding clicks as you’d expect, too.

Geiger counters are a popular project, though we hope they don’t become common household items in the near future. Here’s a Fallout-inspired build for fans of the game. Video after the break.

Continue reading “A PKE Meter That Actually Detects Radiation” →

Radiation Detector Eschews Tubes, Uses Photodiode

February 22, 2019 by 13 Comments

When the topic is radiation detection, thoughts turn naturally to the venerable Geiger-Müller tube. It’s been around for ages, Russian surplus tubes are available for next to nothing, and it’s easy to use. But as a vacuum tube it can be somewhat delicate, and the high voltages needed to run it can be a little on the risky side.

Luckily, there are other ways to see what’s going on in the radioactive world, like this semiconductor radiation detector. [Robert Gawron] built it as a proof-of-concept after having built a few G-M tube detectors before. His solid-state design relies on a reverse-biased photodiode conducting when ionizing radiation hits the P-N junction. The tiny signal is amplified by a pair of low-noise op-amps and output to a BNC connector. The sensor’s analog output is sent to an oscilloscope whose trigger out is connected to a Nucleo board for data acquisition. The Nucleo is in turn connected to a Raspberry Pi for totalizing and logging. It’s a complicated chain, but the sensor appears to work, even detecting alpha emissions from thoriated TIG electrodes, a feat we haven’t been able to replicate with our G-M tube counter.

[Robert]’s solid-state detector might not be optimal, but it has promise. And we have seen PIN diodes used as radiation detectors before, too.

[via Dangerous Prototypes]