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I cooked myself with RF when I was a teenager. Well, it was just my finger, but did it ever hurt! I was setting up a new ham radio transmitter and antenna. I

I cooked myself with RF when I was a teenager. Well, it was just my finger, but did it ever hurt! I was setting up a new ham radio transmitter and antenna. I don't remember what I did wrong, but I got a nasty RF burn in my finger. That's "in", not "on". Imagine a bad burn, but one where you can tell it's not just on the surface but goes deep into the tissue. And takes quite some time to heal. I did have a lot of fun with ham radio, that one experience aside.

dataflow 5y ago
> And takes quite some time to heal. Damn. How many years(?) did it take to heal? Did it heal fully or do you still have any residual effects?
- Stratoscope 5y ago
  Oh, it wasn't that long, just longer than a surface burn. And weird too: it didn't look nearly as bad on my skin as a typical blistering burn, but somehow I could feel that it went much deeper. Luckily, I don't think my radio activities left any residual effects. Wait, what did you just say?
- formerkrogemp 5y ago
  From that day onward, they could receive FM/AM signal directly to their consciousness using their RF empowered finger-antenna, and they swore always to use their powers for the greater good. Nothing could possibly go wrong from there. Jokes aside, I wonder what effect intensive RF bursts could have on tissue compared to UV exposure or a burn?
  - robbedpeter 5y ago
    Color blindness is a common injury among incautious radio engineers who stood in front of transmitters too many times. Dish Network's satellite uplink station in Wyoming can "burn" away cloud cover when needed, and unfortunate birds have gotten cooked when they've flown over particularly intense beams.
    - formerkrogemp 5y ago
      I had no idea it was that dangerous. Thank you for informing. I didn't mean to make light of the danger.
hilbert42 5y ago
I've worked on broadcast transmitter masts. I recall on FM masts RF burns were commonplace (things were a little different on TV towers). To minimize RF burns, the idea was to grab metal surfaces quickly so as to not get an RF burn (doing this avoided RF arcing onto one's skin). One of the notable problems was when one's body could not come into direct contact with the metal mast. For example, one's on the mast/tower and working on something and one's legs are wrapped around the center pole of the antenna. In this situation one's legs are actually separated from the pole's metal surface by the thickness of the material in one's pants. I recall ruining perfectly good pairs of jeans and overalls when the RF burned holes in them around the point of my knees (my knees being the closest point to the metal pole). It was annoying for me to have to keep shifting about to minimize the RF arcing onto my knees (I say 'minimize' because I couldn't stop it completely). After alighting down from the tower and inspecting my jeans it was not unusual to find about a half dozen blackened holes of a few mm (1/8") in diameter on the inside of both legs at knee height. Right, RF arcs through my pants did cause RF burns but for some reason they didn't hurt as much as I'd have expected. They were just a bit of a nuisance really. BTW, when the arcing was happening I could smell whiffs of myself burning. At the time I considered this no big deal and I still don't. If one has to work on 'live' towers that are radiating VHF broadcast signals then one has to take these minor hazards/annoyances as part of the job. ___ Edit: I accidentally wore my good Seiko watch with an LCD on the tower one day and its display was ruined (the screen went completely black). Lesson: no electronic watches on 'live' towers. Wind-up mechanical ones are OK. Also, do not attempt to use electronic multimeters on 'live' towers either (destroying a perfectly good Fluke won't get you any Brownie points). If you must use a multimeter on a 'live' tower, an AVO-8 is OK as long as the field strength isn't too high (figuring that out can be a problem which I won't address here, except to say that the field strength (power absorbed in the meter's components, i.e.: I^2R losses), should not exceed their limit). The reason you can use an AVO-8 is that it uses a copper oxide rectifier which has an f(t) of around 20kHz. Note: there is no other multimeter that I know of with a copper oxide rectifier - all others use germanium diodes and the RF will blow them sky-high.
euroderf 5y ago
I cooked my brain with a phone. Many years ago I stepped off the plane in ATL with a European 3G phone, turned it on, wondering if it could connect. Held it to my head while it tried to connect. MISTAKE. Not finding base stations on its wavelength, it probably cranked up the power. I had a really weird and uncomfortable headache for two or three days after that. Do not try this at home!
- Genbox 5y ago
  The maximum power output of a mobile phone is ~200 mW (0.2 watt) and that happens only for short periods (miliseconds) at the time. That is not enough energy to even penetrate the skin, much less the skull. The amount of energy the article talks about is 1000x that amount and for an extended amount of time. A lot of travelers experience headache after flying. Blood pressure changes, blocked sinuses, CO2 accumulation, change in sleep cycles etc. can all contribute. Source: degree in technical medicine
  - euroderf 5y ago
    OK, good to know. It was a genuinely weird headache, but I misattribute it.
  - kaba0 5y ago
    Wow, really interesting degree I haven’t heard much about. Could you please tell a bit on what are you working on/what could you work on with this title?

dataflow 5y ago

> And takes quite some time to heal. Damn. How many years(?) did it take to heal? Did it heal fully or do you still have any residual effects?

Stratoscope 5y ago
Oh, it wasn't that long, just longer than a surface burn. And weird too: it didn't look nearly as bad on my skin as a typical blistering burn, but somehow I could feel that it went much deeper. Luckily, I don't think my radio activities left any residual effects. Wait, what did you just say?
formerkrogemp 5y ago
From that day onward, they could receive FM/AM signal directly to their consciousness using their RF empowered finger-antenna, and they swore always to use their powers for the greater good. Nothing could possibly go wrong from there. Jokes aside, I wonder what effect intensive RF bursts could have on tissue compared to UV exposure or a burn?
- robbedpeter 5y ago
  Color blindness is a common injury among incautious radio engineers who stood in front of transmitters too many times. Dish Network's satellite uplink station in Wyoming can "burn" away cloud cover when needed, and unfortunate birds have gotten cooked when they've flown over particularly intense beams.
  - formerkrogemp 5y ago
    I had no idea it was that dangerous. Thank you for informing. I didn't mean to make light of the danger.

hilbert42 5y ago

I've worked on broadcast transmitter masts. I recall on FM masts RF burns were commonplace (things were a little different on TV towers). To minimize RF burns, the idea was to grab metal surfaces quickly so as to not get an RF burn (doing this avoided RF arcing onto one's skin). One of the notable problems was when one's body could not come into direct contact with the metal mast. For example, one's on the mast/tower and working on something and one's legs are wrapped around the center pole of the antenna. In this situation one's legs are actually separated from the pole's metal surface by the thickness of the material in one's pants. I recall ruining perfectly good pairs of jeans and overalls when the RF burned holes in them around the point of my knees (my knees being the closest point to the metal pole). It was annoying for me to have to keep shifting about to minimize the RF arcing onto my knees (I say 'minimize' because I couldn't stop it completely). After alighting down from the tower and inspecting my jeans it was not unusual to find about a half dozen blackened holes of a few mm (1/8") in diameter on the inside of both legs at knee height. Right, RF arcs through my pants did cause RF burns but for some reason they didn't hurt as much as I'd have expected. They were just a bit of a nuisance really. BTW, when the arcing was happening I could smell whiffs of myself burning. At the time I considered this no big deal and I still don't. If one has to work on 'live' towers that are radiating VHF broadcast signals then one has to take these minor hazards/annoyances as part of the job. ___ Edit: I accidentally wore my good Seiko watch with an LCD on the tower one day and its display was ruined (the screen went completely black). Lesson: no electronic watches on 'live' towers. Wind-up mechanical ones are OK. Also, do not attempt to use electronic multimeters on 'live' towers either (destroying a perfectly good Fluke won't get you any Brownie points). If you must use a multimeter on a 'live' tower, an AVO-8 is OK as long as the field strength isn't too high (figuring that out can be a problem which I won't address here, except to say that the field strength (power absorbed in the meter's components, i.e.: I^2R losses), should not exceed their limit). The reason you can use an AVO-8 is that it uses a copper oxide rectifier which has an f(t) of around 20kHz. Note: there is no other multimeter that I know of with a copper oxide rectifier - all others use germanium diodes and the RF will blow them sky-high.

euroderf 5y ago

I cooked my brain with a phone. Many years ago I stepped off the plane in ATL with a European 3G phone, turned it on, wondering if it could connect. Held it to my head while it tried to connect. MISTAKE. Not finding base stations on its wavelength, it probably cranked up the power. I had a really weird and uncomfortable headache for two or three days after that. Do not try this at home!

Genbox 5y ago
The maximum power output of a mobile phone is ~200 mW (0.2 watt) and that happens only for short periods (miliseconds) at the time. That is not enough energy to even penetrate the skin, much less the skull. The amount of energy the article talks about is 1000x that amount and for an extended amount of time. A lot of travelers experience headache after flying. Blood pressure changes, blocked sinuses, CO2 accumulation, change in sleep cycles etc. can all contribute. Source: degree in technical medicine
- euroderf 5y ago
  OK, good to know. It was a genuinely weird headache, but I misattribute it.
- kaba0 5y ago
  Wow, really interesting degree I haven’t heard much about. Could you please tell a bit on what are you working on/what could you work on with this title?