Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [radiation]

While rare, this tag should be used for questions pertaining to using electronic devices (passive or active) in an ionizing radiation environment. This could be space, medical facilities or physics labs. Defense or military related questions are probably classified.

164 questions
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What's radiating on my PCB?

I recently did a proper EMC test on a PCB of mine. It failed the test, and seems to be radiating in the 300MHz - 1GHz region, with peaks every 50MHz, and little peaks on the 25MHz. Looking at the near field, you can clearly see lots of 25MHz…
Rocketmagnet
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Why is an inductor not a good antenna?

[An antenna must have] current flowing along its length, so that the resulting fields radiate that energy into space. (Receiving antennas are just this process in reverse). [This] explains why you can't just stick a small tank circuit on a board…
Phil Frost
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Why do radiation hardened IC packages often have long leads?

What purpose do long leads serve?
Dojo
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Can antennas be viewed as light sources?

Clearly antennas are nothing but a device to radiate the electrical energy through electromagnetic waves. Since visible light is also simply a certain range of frequencies, isn't it more easier to think of antennas as different shapes of "light"…
Vishwa Mithra Tatta
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Are there any advantages to using rigid RF coaxial cables?

While watching this Signal Path video, I came across this shot: I saw few rigid coaxial cables there and so I started wondering what might their advantages be. I could only find disadvantages: They're expensive Limited in available angles 45° or…
HatimB
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Are chicken bits left in space-qualified ICs?

A chicken bit "is a bit on a chip that can be used by the designer to disable one of the features of the chip if it proves faulty or negatively impacts performance." Would space-qualified logic components leave this feature in, or would the final…
My Other Head
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What is a "half latch" in an FPGA?

In a paper about radiation hard FPGAs I came across this sentence: "Another concern regarding Virtex devices is half latches. Half latches are sometimes used within these devices for internal constants, as this is more efficient than using…
andrsmllr
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What makes E-bomb or Electromagnetic pulse (EMP) destructive?

wikipedia says that Electromagnetic pulse As with any electromagnetic signal, EMP energy may be transferred in any of four forms: Electric field Magnetic field Electromagnetic radiation Electrical…
Michael George
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What effect does Gamma radiation sterilisation have on embedded electronics devices

We just received back 3 pieces of equipment that may have been inadvertently put through a Gamma radiation sterilisation process. The equipment is a low-power embedded device consisting of a 16 bit microcontroller with peripheral FLASH memory and…
geometrikal
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Design Considerations for Electronics in Space

What additional constraints do we face when designing electronics/microsystems for use in orbit? What kinds of shielding techniques are employed? Is it common to enclose all electronics in a faraday cage, or are other shielding methods…
RYS
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Is there a simple Geiger counter component?

I'm looking for a simple electronic Geiger counter element. In my design I need to detect radiation and did not know what my options were for components to detect radiation. What components exist for my need and what kind of complexity is associated…
powtac
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Can leaving a Geiger–Müller tube energized continuously cause it to wear out?

I recently acquired a Geiger counter to feed my raging paranoia curiosity. However, I am wondering if it could harm the Geiger–Müller tube to leave it energized continuously? I know a couple places (spark fun, for one) Have continuously operating…
Connor Wolf
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Do electromagnetic shielding stickers do anything?

I recently bought some cellphone accessories, and as a free gift, the merchant gave me a "24K gold plating electromagnetic shielding sticker", whose instructions are all in Chinese, but I guess you're supposed to stick it onto your cellphone, and…
Shaul Behr
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Insight into cavity resonators

Modes of a waveguide As shown in the link above, they show how these modes work for various values of m, n, and p. However, where is the antenna/ source of radiation placed within the cavity? From the picture I have shown the placement of 4 antennas…
JoeyB
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Visual understanding of EM fields within a rectangular metal container

I have the following scenario setup inside a rectangular metal container. The container size is 12.03m by 2.39m by 1.84m (lxbxh). Additionally, inside the container I have placed 4 antennas equally spaced, this is shown using the green squares…
JoeyB
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