My Very First RF Burn!
Created by on 2015-05-26I am not the smartest of the people in the world. -- No, far from it. I am now 59 years old, but my 'radio' experiences started at my tender age of 9.
My Dad was a forestry technician in the northern part of Quebec. He had a beautiful office, and a lovely company house. Sometimes in the evening, maybe once or twice a month, he would take me with him as he headed back to work, get on what looked like a 160M dipole, and talk on AM to the fellows up in the lumber camps. He would fire up the company radio, a Hallicrafters I believe, and chat away about how a new piece of equipment was operating. I gather his role was to evaluate the new and upcoming forestry equipment to see if the company should invest in it or not.
So, at a tender age, young, (and handsome), Dan was introduced to HF. A year later, I went swimming. The swimming hole was located a good 3 miles from home, so it was a bit of a hike. Normally I would follow the road around a large field to the tiny beach. You would never dare cut across the field because it was home to a large bull.
I had a great time swimming, and finally had to face the march home for supper. That shortcut across the field looked very tempting. It would save me 10 minutes or more. The bull was nowhere to be seen. In the middle of the field was the local AM broadcast station vertical tower. -- All nicely painted red and white. It was gorgeous! I ducked under the fence, and headed for the tower. It was exactly where the shortest distance in my shortcut would take me.
As I approached this work of art, this marvel of engineering, this magical radio thing, this gleaming structure standing so tall, I noticed something. A ground strap! The strap was a piece of heavy tin about 3" wide. I didn't figure out what it was hooked to on the tower side, but it had been carefully bent in fine style out and over the concrete base that supported this heavenly beauty. It was meticulously contoured to follow the base down towards mother earth, where it disappeared in the grass. Nice, I thought, very nice. With a young, clean, outreached finger I chose to carefully 'touch' this wonderful workmanship, to give it my blessing, to commend the individual who had taken so much care in its installation.
The 'touch of Dan' turned into a jolt of the most excruciating pain I had ever felt. The current rippled up through my (ever so masculine) 10-year-old arm, through my upper body (Charles Atlas, of course), into my hungry stomach, down my both legs, out my tennis shoe shoelaces, and into the immediate area I was standing in. 'HOLY COW' I kept repeating as I did the proverbial dance of stricken heroes. 'GEEZ' was all I could formulate as my heart rate dropped from 300 BPM. 'WHEW' as I quickly scanned to see if there were any witnesses, and in particular of the Bull type.
So I made it home, I didn't speak of the event. I kept it to myself and finally decided to share it with you fine folks.
It was only 30 years later that I stepped into a canoe with an HF rig, a battery, a vertical, and a trailing bare metal ground. But that is another burn, sorry story.
VE9DAN
| W1BR | 2015-06-30 | |
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| My Very First RF Burn! | ||
| RF burns are generally very localized... brutally painful, and they take a long time to heal. I've experience both--RF burns, and one incident where I managed to get across a 2kV power supply and ground, through both arms. The 2kv jolt was painful, and felt throughout my entire body! I was 19 years old, and I am lucky to be alive. I've had numerous RF burns in my ham and commercial two way radio and broadcasting career... while painful, few RF burns are life threatening, they can cause heart fibrillation as a rule. But, the effects last for sometime. Pete | ||
| K3JLS | 2015-06-28 | |
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| My Very First RF Burn! | ||
| This is not a very spectacular story, but I'll include it anyway. I was first licensed back in 1959 and used a DX-20, a Hallicrafters S-85 and a windom antenna. The antenna was switched between the transmitter and the receiver with a knife switch about one foot from the rig desk. Switching from receive to a transmit was a 3 switch deal - mute the S-85, switch the antenna, activate the DX-20 B+, and then transmit. On more than one occasion, I was holding onto the knife switch while transmitting the final characters before reverting to the receive mode while I first noticed a burning sensation on one of my fingers followed by the faint scent of burned chicken. Nothing spectacular, but noteworthy - at least to me. On subsequent occasions while working on a 100 watt GE Delta 2 meter rig I accidentally touched the PA stage while tuning up, and this really smarted - big blisters and all of that. It took a while for my finger to stop quivering. 73's - Joe - K3JLS | ||
| KE0ANY | 2015-06-23 | |
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| My Very First RF Burn! | ||
| The first I got a sting (not really a burn) was when I was cleaning out my HT. I had it in my pocket all day and there was a bunch of lint in the SMA port. So I grabbed a kleenex and started to clean it out and not knowing that is was on, I accidentally bumped the ptt. It was set for a watt and it felt like I had just stuck my finger under the beam of a magnifying glass! Considering 144 MHz and light frequencies are both electro magnetic waves it makes sense that they would feel the same. The other time I got stung was when I made a counterpoise out of uninsulated 22 gage wire for my HT. That time it was set for 5 watts and that hurt! I quickly went to the hardware store and got some Bell wire (aka insulated 22 gage wire, no more burns) and that fixed the problem. 73 -.. . Peter KEØANY | ||
| WB9YCJ | 2015-06-06 | |
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| My Very First RF Burn! | ||
| Field Day ..... a jovial place to experience your very first RF Burn. | ||
| K1YPB | 2015-06-01 | |
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| My Very First RF Burn! | ||
| When I was a teenage novice in 1962, touched the loading coil of my vertical with about 25 watts on the antenna... burn spot the size of a pin head right down to the bone. Felt like touching a hot frying pan. Never did it again! | ||
| W4CX | 2015-06-01 | |
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| RE: My Very First RF Burn! | ||
| Still carrying around a scar on my back that came from doing some "weed maintenance" around the RF doghouse. Hot, sweaty 17 year old RF nut and Novice with no shirt on, (me: WN4LFB) backed into the wire around the tapered self supporting tower. Hurt like heck, and momentarily found out what a diode detector does, as my skin started to play Gilbert O'Sullivan's "Alone Again, Naturally" which the DJ was playing at the time. He saw the meters bouncing and came outdoor to see what happened. To this day I still hate that song! Reminds me of the small of burning flesh. :-) Reply to a comment by : KC8MWG on 2015-05-31 My dad was in the navy from 1967 to 1993 (with a short gap from 1971 to 1973). From 1973 to 1975, he was stationed on the USS Hancock (CV-19). TOld me that when they fired up the radar on "Hannah", it would often trigger garage door openers all over Alameda and the surrounding neighborhoods! Nearest I came, I think it was just major static shock. I had my Ten-Tec Omni D (Series B) hooked up to a full-wave 80 meter loop up in the trees, and an MFJ 2-40 meter vertical for my VHF equipment (and occasional HF use). We had a thunderstorm rolling in so I started to disconnect my antennas and short them to ground. THe transceivers were all turned off and unplugged. Just as I connected my antenna switch directly to ground, I got one heck of a zap, right before I heard a clap of thunder. Felt like I had stuck my hand in a light socket! No burns, as far as I could tell, but my hand tingled for several minutes... | ||
| KC8MWG | 2015-05-31 | |
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| My Very First RF Burn! | ||
| My dad was in the navy from 1967 to 1993 (with a short gap from 1971 to 1973). From 1973 to 1975, he was stationed on the USS Hancock (CV-19). TOld me that when they fired up the radar on "Hannah", it would often trigger garage door openers all over Alameda and the surrounding neighborhoods! Nearest I came, I think it was just major static shock. I had my Ten-Tec Omni D (Series B) hooked up to a full-wave 80 meter loop up in the trees, and an MFJ 2-40 meter vertical for my VHF equipment (and occasional HF use). We had a thunderstorm rolling in so I started to disconnect my antennas and short them to ground. THe transceivers were all turned off and unplugged. Just as I connected my antenna switch directly to ground, I got one heck of a zap, right before I heard a clap of thunder. Felt like I had stuck my hand in a light socket! No burns, as far as I could tell, but my hand tingled for several minutes... | ||
| W3DCB | 2015-05-30 | |
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| My Very First RF Burn! | ||
| I, too remember my first RF burn...It was sooooooooooooooo painful. Much worse than a heat or burn from plain old AC. The pain lasted for many days. I was about 12...sort of a similar story, although I was working on my first ham lic. which I got at age 12, WB2MJB. I had no excuse as I new a bit about RF. Brings back some interesting memories. I also kept it to myself. I was way too embarrassed to tell anyone. The wound to my hand was there for all to see, but no one noticed! de W3DCB Daniel | ||
| W8LV | 2015-05-30 | |
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| My Very First RF Burn! | ||
| In High School Electronics Class, I accidently brushed up against the top cap of a television tube. Ouch! I still have a little perfectly round hole on my left hand where that happened in 1978. When I get in the shower, the adjacent tissue turns white, now thirty seven years later. I guess I never thought of it as an RF burn, but I guess after reading this that is what it is. | ||
| AA3M | 2015-05-30 | |
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| RE: My Very First RF Burn! | ||
| A very long time indeed. I must defer to your better mental storage capacity Tom. I must also learn to hold off on hitting the send button before I have to spend more time correcting myself. I realize once I hit go on my reply, the 3.2MW ERP should have been closer to 3.2MW PEAK power. Searching around on line is difficult since the 48 has been around forever. You are correct it (latest version) is nothing like the original, so pick one :) One number that seems to be close among the ones I could find is an average output power of 35KW. I see published peak power ratings of about 2.5MW. Sorry for the confused ramblings of a madman. 73 John Reply to a comment by : K5MF on 2015-05-28 John AA3M You know, it has been a long time, 1973-1979, and I couldn't remember if it was power or volts. I seemed to remember the meter on the final stage reading 3.2 but couldn't remember if it was power or voltage. Or maybe I am just recalling something totally wrong and the meters didn't read 3.2 at all. However, I do remember taking off the doors to the transmitter and seeing that eerie purple corona glow around the HV voltage leads. It made great mood lighting when the compartment overhead lights were off. I guess the radar is up 48G version now and it is quite different from the A version. Those were the good ole days, although I didn't realize it at the time. Thanks for the clarification. Be safe! Tom/K5MF Reply to a comment by : AA3M on 2015-05-27 Tom, I believe that we're talking about 3.2 MEGAWATTS ERP. The pulser ran about 35 kilo-volts, but the capacitive pulser circuit gave this 35kv a deadly kick. Getting in the beam was not something to trifle with either. Safest place is below-deck. :) 73 John AA3M Reply to a comment by : K5MF on 2015-05-26 Funny! If you haven't been bit at least a couple of times you aren't trying very hard. My Navy days working on the AN/SPS 48A radar provided some fond and not so fond memories. Lets see, voltages of 3.2 megavolts, steel ship, floating in salt water, 2-near death experiences. What's not to like? This KW stuff is small potatoes. 73, Tom/K5MF | ||
| G3RZP | 2015-05-30 | |
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| RE: My Very First RF Burn! | ||
| In 1925, Gerry, G2XV (SK for many years now) got an RF burn from his 40 metre transmitter. In 1969, he still had the white patch on his finger....... RF burns rarely go septic because of cauterisation. Best kept away from though, although a cigarette could be lit with the arc from the antenna terminal to a screwdriver from a 2 MHz 100 watt marine radio! Reply to a comment by : KE4ZHN on 2015-05-29 Ouch! Sounds like you latched onto the feed point of the vertical. You're lucky to be alive. Had that been a full 50kw broadcast rig you may not have survived. My brother Jim K9YQQ is a long time broadcast engineer. Many years ago while working in a small 5kw AM station he accidentally brushed up against a large coil in the tuning house while the rig was on the air. He got a nasty RF burn on his chest from it right through his shirt that he said felt like fire inside of him. Not fun. It took weeks to heal. RF is nothing to take lightly, it will bite you. | ||
| KE4ZHN | 2015-05-29 | |
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| My Very First RF Burn! | ||
| Ouch! Sounds like you latched onto the feed point of the vertical. You're lucky to be alive. Had that been a full 50kw broadcast rig you may not have survived. My brother Jim K9YQQ is a long time broadcast engineer. Many years ago while working in a small 5kw AM station he accidentally brushed up against a large coil in the tuning house while the rig was on the air. He got a nasty RF burn on his chest from it right through his shirt that he said felt like fire inside of him. Not fun. It took weeks to heal. RF is nothing to take lightly, it will bite you. | ||
| AB1UP | 2015-05-28 | |
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| RE: My Very First RF Burn! | ||
| Glad I started ham radio with low power rigs. First rf burns were from un-insulated parts of a telegraph key while using a Johnson Adventurer (a lowly 807 tube). Second burn was when I was adjusting the tap on a vertical and my brother thought it would be great fun to key the transmitter while I was in contact with the antenna, luckily it was another low power rig. I also learned the lesson of one hand in the back pocket when working with HV. I once managed to get my right arm inside a 70's vintage video display which made contact with the flyback circuit. The display catapulted across a room. Today I assume all HV circuits, transmitter and antenna parts are live. 73's AB1UP Reply to a comment by : K5MF on 2015-05-28 John AA3M You know, it has been a long time, 1973-1979, and I couldn't remember if it was power or volts. I seemed to remember the meter on the final stage reading 3.2 but couldn't remember if it was power or voltage. Or maybe I am just recalling something totally wrong and the meters didn't read 3.2 at all. However, I do remember taking off the doors to the transmitter and seeing that eerie purple corona glow around the HV voltage leads. It made great mood lighting when the compartment overhead lights were off. I guess the radar is up 48G version now and it is quite different from the A version. Those were the good ole days, although I didn't realize it at the time. Thanks for the clarification. Be safe! Tom/K5MF Reply to a comment by : AA3M on 2015-05-27 Tom, I believe that we're talking about 3.2 MEGAWATTS ERP. The pulser ran about 35 kilo-volts, but the capacitive pulser circuit gave this 35kv a deadly kick. Getting in the beam was not something to trifle with either. Safest place is below-deck. :) 73 John AA3M Reply to a comment by : K5MF on 2015-05-26 Funny! If you haven't been bit at least a couple of times you aren't trying very hard. My Navy days working on the AN/SPS 48A radar provided some fond and not so fond memories. Lets see, voltages of 3.2 megavolts, steel ship, floating in salt water, 2-near death experiences. What's not to like? This KW stuff is small potatoes. 73, Tom/K5MF | ||
| K0UA | 2015-05-28 | |
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| RE: My Very First RF Burn! | ||
| I have had 2 or 3 RF burns when I worked on VHF and UHF transmitters every day. I can't remember the details of the incidents, but I remember the results pretty well. Usually a small white area of dead meat on a thumb or finger. Sometimes the white chunk would fall out after a period of time, leaving a small pit. It seemed like the whole healing process too a very long time. I have never had an HF or MF burn, and I am happy to stay that way. :) Reply to a comment by : K5MF on 2015-05-28 John AA3M You know, it has been a long time, 1973-1979, and I couldn't remember if it was power or volts. I seemed to remember the meter on the final stage reading 3.2 but couldn't remember if it was power or voltage. Or maybe I am just recalling something totally wrong and the meters didn't read 3.2 at all. However, I do remember taking off the doors to the transmitter and seeing that eerie purple corona glow around the HV voltage leads. It made great mood lighting when the compartment overhead lights were off. I guess the radar is up 48G version now and it is quite different from the A version. Those were the good ole days, although I didn't realize it at the time. Thanks for the clarification. Be safe! Tom/K5MF Reply to a comment by : AA3M on 2015-05-27 Tom, I believe that we're talking about 3.2 MEGAWATTS ERP. The pulser ran about 35 kilo-volts, but the capacitive pulser circuit gave this 35kv a deadly kick. Getting in the beam was not something to trifle with either. Safest place is below-deck. :) 73 John AA3M Reply to a comment by : K5MF on 2015-05-26 Funny! If you haven't been bit at least a couple of times you aren't trying very hard. My Navy days working on the AN/SPS 48A radar provided some fond and not so fond memories. Lets see, voltages of 3.2 megavolts, steel ship, floating in salt water, 2-near death experiences. What's not to like? This KW stuff is small potatoes. 73, Tom/K5MF | ||
| K5MF | 2015-05-28 | |
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| RE: My Very First RF Burn! | ||
| John AA3M You know, it has been a long time, 1973-1979, and I couldn't remember if it was power or volts. I seemed to remember the meter on the final stage reading 3.2 but couldn't remember if it was power or voltage. Or maybe I am just recalling something totally wrong and the meters didn't read 3.2 at all. However, I do remember taking off the doors to the transmitter and seeing that eerie purple corona glow around the HV voltage leads. It made great mood lighting when the compartment overhead lights were off. I guess the radar is up 48G version now and it is quite different from the A version. Those were the good ole days, although I didn't realize it at the time. Thanks for the clarification. Be safe! Tom/K5MF Reply to a comment by : AA3M on 2015-05-27 Tom, I believe that we're talking about 3.2 MEGAWATTS ERP. The pulser ran about 35 kilo-volts, but the capacitive pulser circuit gave this 35kv a deadly kick. Getting in the beam was not something to trifle with either. Safest place is below-deck. :) 73 John AA3M Reply to a comment by : K5MF on 2015-05-26 Funny! If you haven't been bit at least a couple of times you aren't trying very hard. My Navy days working on the AN/SPS 48A radar provided some fond and not so fond memories. Lets see, voltages of 3.2 megavolts, steel ship, floating in salt water, 2-near death experiences. What's not to like? This KW stuff is small potatoes. 73, Tom/K5MF | ||
| VE3TMT | 2015-05-28 | |
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| My Very First RF Burn! | ||
| Welcome to the fraternity Dan! You've no doubt heard of "serviceman's elbow"? 800V, not once, but twice , from an FT101E. Gosh I loved that radio. We developed quite a respect for each other after that. And I am very careful around concrete walls now too! 73 VE3TMT | ||
| N9DWE | 2015-05-28 | |
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| RE: My Very First RF Burn! | ||
| I was in the US Navy some 40 years ago and can still remember getting an RF burn while working on a VHF transmitter. It seemed to take forever before my thumb finally healed. Glad we can all talk about it. 73's Reply to a comment by : AA3M on 2015-05-27 Tom, I believe that we're talking about 3.2 MEGAWATTS ERP. The pulser ran about 35 kilo-volts, but the capacitive pulser circuit gave this 35kv a deadly kick. Getting in the beam was not something to trifle with either. Safest place is below-deck. :) 73 John AA3M Reply to a comment by : K5MF on 2015-05-26 Funny! If you haven't been bit at least a couple of times you aren't trying very hard. My Navy days working on the AN/SPS 48A radar provided some fond and not so fond memories. Lets see, voltages of 3.2 megavolts, steel ship, floating in salt water, 2-near death experiences. What's not to like? This KW stuff is small potatoes. 73, Tom/K5MF | ||
| AA3M | 2015-05-27 | |
|---|---|---|
| RE: My Very First RF Burn! | ||
| Tom, I believe that we're talking about 3.2 MEGAWATTS ERP. The pulser ran about 35 kilo-volts, but the capacitive pulser circuit gave this 35kv a deadly kick. Getting in the beam was not something to trifle with either. Safest place is below-deck. :) 73 John AA3M Reply to a comment by : K5MF on 2015-05-26 Funny! If you haven't been bit at least a couple of times you aren't trying very hard. My Navy days working on the AN/SPS 48A radar provided some fond and not so fond memories. Lets see, voltages of 3.2 megavolts, steel ship, floating in salt water, 2-near death experiences. What's not to like? This KW stuff is small potatoes. 73, Tom/K5MF | ||
| K2IZ | 2015-05-27 | |
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| My Very First RF Burn! | ||
| Navy days, when there was work to be done aloft, up on the mast for you landlubbers, you had to bring around a check off list that had to be signed, the Radar Men in CIC so they wouldn't light off the radar, the Fire Control Techs, so they wouldn't light off the Fire Control radar, the Radio Men, they would sign off and then put a long sheet of TTY paper down the front of every transmitter "DO NOT ENERGIZE, MEN WORKING ALOFT" and finally down to main control in the engine room to make sure the snipes didn't let the safety valve blow, that sounded at first like the rumble of an oncoming train followed by a very loud boom that was like a cannon going off as the steam released from the after stack. Even with that there were a few incidents, luckily nothing major. | ||
| ONAIR | 2015-05-27 | |
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| RE: My Very First RF Burn! | ||
| Got mine when I had my finger on an SO 239 connector in the back of an old CB tube transceiver, and I accidentally keyed the mike! Not fun. Reply to a comment by : K5MF on 2015-05-27 One more comment. Just like aircraft accidents it is usually a series of little mistakes that leads to a big problem. While on the USS John F Kennedy we had a tech working on a little radar system used to glide aircraft down to the deck. It was a small device about the size of a toilet. While standing in front of it a fellow shipmate turned it on because the flight officer said he needed the radar up. The young man began experiencing sight problems within a day and ultimately had to be medically discharged for nearly total blindness. An investigation showed several little mistakes that led to the mishap. Another incident occurred while I served aboard a light cruiser. A shipmate decided he wanted to get a picture of a Terrier missile launch. He made his way to forecastle and got there just about the time the launch was executed. Instant crispy critter and over the side he went. Again, several little breakdowns that led up to the incident. There were plenty of safeguards in place to prevent it. I never did see the picture he took. I bet it was awesome. Be careful, check twice, communicate with others. 73, Tom/K5MF | ||
| K5MF | 2015-05-27 | |
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| My Very First RF Burn! | ||
| One more comment. Just like aircraft accidents it is usually a series of little mistakes that leads to a big problem. While on the USS John F Kennedy we had a tech working on a little radar system used to glide aircraft down to the deck. It was a small device about the size of a toilet. While standing in front of it a fellow shipmate turned it on because the flight officer said he needed the radar up. The young man began experiencing sight problems within a day and ultimately had to be medically discharged for nearly total blindness. An investigation showed several little mistakes that led to the mishap. Another incident occurred while I served aboard a light cruiser. A shipmate decided he wanted to get a picture of a Terrier missile launch. He made his way to forecastle and got there just about the time the launch was executed. Instant crispy critter and over the side he went. Again, several little breakdowns that led up to the incident. There were plenty of safeguards in place to prevent it. I never did see the picture he took. I bet it was awesome. Be careful, check twice, communicate with others. 73, Tom/K5MF | ||
| K9MHZ | 2015-05-27 | |
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| RE: My Very First RF Burn! | ||
| >>>>Another story heard was a tech at a AM transmitter in Peru was working around it. He never came home that weekend. When they went looking for him they found him in the works totally charred black........hopefully he did not suffer too much.<<<<< Something similar happened years ago when the VOA still operated a shortwave transmitter here. I think it was plate voltage, but the same result. Gruesome. Reply to a comment by : HAMMYGUY on 2015-05-27 As a Novice I had an Ameco AC-1 with the exposed screws for an antenna connector. Somehow I touched the center conductor while key down testing some inverted V. The smell of burning flesh is what really got my attention and caused me to jump back. 5-6 watts didn't cause any pain though. I had a wart for years on that finger caused by the RF. Reply to a comment by : AI4WC on 2015-05-27 Thanks, guys! I've never had an RF burn, and now I'm even more sure that I will remember, and apply, these lessons! A few moments of not paying attention can be painful and/or deadly. Reply to a comment by : K1EBU on 2015-05-27 Back in my Novice days as a 14 year old newbie had touched the exposed screw of a banana plug attaching a longwire to MFJs first tuner while keying the DX40. I still have the pencil lead sized burn mark on my index finger 35 years later. I remember that it had hurt for weeks. That was at 40 watts. I can't even imagine a full gallon or more. Ouch. I haven't done that since! 73 Gary | ||
| WD8OOJ | 2015-05-27 | |
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| My Very First RF Burn! | ||
| HAHAHA< WOW Dan you made my day with this, even reading it at work here in OHIO i was cracking UP. Thankyou , HAHAHAHAHAHAHAHA | ||
| HAMMYGUY | 2015-05-27 | |
|---|---|---|
| RE: My Very First RF Burn! | ||
| As a Novice I had an Ameco AC-1 with the exposed screws for an antenna connector. Somehow I touched the center conductor while key down testing some inverted V. The smell of burning flesh is what really got my attention and caused me to jump back. 5-6 watts didn't cause any pain though. I had a wart for years on that finger caused by the RF. Reply to a comment by : AI4WC on 2015-05-27 Thanks, guys! I've never had an RF burn, and now I'm even more sure that I will remember, and apply, these lessons! A few moments of not paying attention can be painful and/or deadly. Reply to a comment by : K1EBU on 2015-05-27 Back in my Novice days as a 14 year old newbie had touched the exposed screw of a banana plug attaching a longwire to MFJs first tuner while keying the DX40. I still have the pencil lead sized burn mark on my index finger 35 years later. I remember that it had hurt for weeks. That was at 40 watts. I can't even imagine a full gallon or more. Ouch. I haven't done that since! 73 Gary | ||
| AI4WC | 2015-05-27 | |
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| RE: My Very First RF Burn! | ||
| Thanks, guys! I've never had an RF burn, and now I'm even more sure that I will remember, and apply, these lessons! A few moments of not paying attention can be painful and/or deadly. Reply to a comment by : K1EBU on 2015-05-27 Back in my Novice days as a 14 year old newbie had touched the exposed screw of a banana plug attaching a longwire to MFJs first tuner while keying the DX40. I still have the pencil lead sized burn mark on my index finger 35 years later. I remember that it had hurt for weeks. That was at 40 watts. I can't even imagine a full gallon or more. Ouch. I haven't done that since! 73 Gary | ||
| K1EBU | 2015-05-27 | |
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| My Very First RF Burn! | ||
| Back in my Novice days as a 14 year old newbie had touched the exposed screw of a banana plug attaching a longwire to MFJs first tuner while keying the DX40. I still have the pencil lead sized burn mark on my index finger 35 years later. I remember that it had hurt for weeks. That was at 40 watts. I can't even imagine a full gallon or more. Ouch. I haven't done that since! 73 Gary | ||
| KJ4DGE | 2015-05-27 | |
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| RE: Nothing to be proud of. | ||
| maybe not in the same league as the rest but at the other end of the spectrum while working at Heathkit we had a early version of a microwave oven in kit form. This was before I guess the folks made it mandatory to have a interlock installed that turned off the magnetron from working when the door was open. The tech in Hialeah Florida was working on one of these and got third degree burns before he even knew what was happening and had to be rushed to the hospital, it literally cooked him inside. To this day I steer clear of any microwave ovens when they are on, still use them though :) Another story heard was a tech at a AM transmitter in Peru was working around it. He never came home that weekend. When they went looking for him they found him in the works totally charred black........hopefully he did not suffer too much. Reply to a comment by : AI2IA on 2015-05-26 An RF burn is a serious wound that in all but static electricity levels is more than skin surface deep. Like any electric shock, it can be avoided by thinking through a situation BEFORE acting on it. Other things to consider are these: A "minor" shock or RF burn, or if you will, a momentary one, can cause you to lose balance and fall into the equipment under test instead of away from it. It that happens, you can fall victim to a shock from a well-regulated source that will continue to feed current into your body once skin resistance is broken down without an appreciable voltage drop. This could be lethal! Never ever work alone. At least have someone else around who has been instructed enough so that they can shut down the primary power. All ham stations regardless of size should have a electrically approved fire extinguisher and a first aid kit of comparable size to handle the worst situations that may occur. Remember - it only has to happen once to kill you. Have fun, but stay alert, and never any horseplay. | ||
| AI2IA | 2015-05-26 | |
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| Nothing to be proud of. | ||
| An RF burn is a serious wound that in all but static electricity levels is more than skin surface deep. Like any electric shock, it can be avoided by thinking through a situation BEFORE acting on it. Other things to consider are these: A "minor" shock or RF burn, or if you will, a momentary one, can cause you to lose balance and fall into the equipment under test instead of away from it. It that happens, you can fall victim to a shock from a well-regulated source that will continue to feed current into your body once skin resistance is broken down without an appreciable voltage drop. This could be lethal! Never ever work alone. At least have someone else around who has been instructed enough so that they can shut down the primary power. All ham stations regardless of size should have a electrically approved fire extinguisher and a first aid kit of comparable size to handle the worst situations that may occur. Remember - it only has to happen once to kill you. Have fun, but stay alert, and never any horseplay. | ||
| WA0ZZG | 2015-05-26 | |
|---|---|---|
| My Very First RF Burn! | ||
| I don't think that piece of strap was part of the ground system. If it were, you shouldn't have been 'bit' like that. Suspect that was the feed line. You put yourself on the output of a 5KW transmitter and are lucky to be alive. | ||
| K5TED | 2015-05-26 | |
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| RE: My Very First RF Burn! | ||
| One afternoon, early on in my AM broadcasting experience, while checking the hot tower ATU, running 1kW daytime power, I noticed the FM antenna feedline coming off the top of the isocoupler looked to have a bit of weathering around the edge of the jacket/connector junction. I could see copper peeking through, so I thought it would be a good idea to seal that up. I happened to have a tube of latex caulking. The small "toothpaste" tube variety. It did't dawn on me initially that the caulking might contain water. As I squeezed a nice bead all around the connector, at one point something happened.... There was a sharp stabbing like a nail being driven into the side of my thumb, and a pop, crackle, and I could feel the caulking suddenly boil inside the tube. Apparently, the caulking was a fair conductor. I now, and for the next couple of weeks sported a small but really painful hole in my thumb. Reply to a comment by : KK8ZZ on 2015-05-26 Having seen our instructor at Fort Gordon touch a pencil to a bare wire feeding a whip antenna on a radio van (RTTY 400 watts) and watching it immediately catch fire, I developed an instant, healthy respect for the evil Mr. R.F Burns..... not that I didn't get a couple later tuning up Heathkit transceivers, but that's another story..... They hurt. Instructor said they burned from the bone outward. | ||
| KK8ZZ | 2015-05-26 | |
|---|---|---|
| My Very First RF Burn! | ||
| Having seen our instructor at Fort Gordon touch a pencil to a bare wire feeding a whip antenna on a radio van (RTTY 400 watts) and watching it immediately catch fire, I developed an instant, healthy respect for the evil Mr. R.F Burns..... not that I didn't get a couple later tuning up Heathkit transceivers, but that's another story..... They hurt. Instructor said they burned from the bone outward. | ||
| KL7AJ | 2015-05-26 | |
|---|---|---|
| My Very First RF Burn! | ||
| A.M. broadcast frequency R.f. burns are far more painful than anything you can get on H.F. The skin depth is a lot deeper and you can actually burn your bones! I used to be Chief Engineer of a 50 KW AM station with two half-wave towers, spaced 1/4 wave apart. During the daytime, the second tower was not energized.....in theory. I learned very early in my career about mutual coupling between A.M. towers. I was whacking some weeds in the tower enclosure, and brushed my elbow across the ball gaps on this "dead" tower. Yikes! I think you could have smelled the burnt elbow flesh a mile away! :) Eric | ||
| AF6AU | 2015-05-26 | |
|---|---|---|
| RE: My Very First RF Burn! | ||
| This is a wonderful thread/article, I hope others add to the "Doh" moments, as you NEVER forget them... Back to 1973,... A friend of mine's, father, had a 35 foot Chris Craft, 1960's vintage, and he kept the old HF transceiver on board besides the new VHF FM rig as well. The HF rig was in need to have the antenna and ground lines checked and the finals aligned, so I volunteered. I don't remember the make of the Marine HF transmitter, but it used 2 6883B's in parallel just like many Ham rigs used the equal 6146B's. The Final's input and output tuning were ganged and you adjusted them for peak output with trimmers. Being the smart guy, I had made special non-metallic flat blade screwdrivers using Tefzel shafts and carbon fiber sheet for the blade... They worked well having no inductive value. Doing that last little tweak to the final tank circuit, ~130 watts going out, the blade got lose in the shaft, rotating, and making the contact between finger and the trimmer. Carbon fiber sheet IS CONDUCTIVE.. amazingly so... and my body jumped backwards several feet away from the radio and bulkhead, I rolled in a muscle-jerk backwards somersault, through an open engine bay door and down into the engine hold 5 feet below. The GMC 6-71 diesel engine I landed on did a wonderful job of stopping me, and ruining my clothes with a coating of nasty smelling carbon loaded oil. My friend, his father, and his wife were howling with laughter, and handed me a beer as I crawled out. He told me he appreciated the radio work and wiping down the engine. Fortunetly, the fall created more pain and bruises than the shock, but lesson learned. Needless to say I anchored the blades in the shafts, using epoxy and winding a layer of thread, not unlike the way Indians secured arrow points to the arrow shafts. Be careful out there... JML Reply to a comment by : W4XKE on 2015-05-26 I was in a communications van on a Dodge M-37 while in the 138th Signal Bn and it was cold outside. We had a generator supplying power to our radios, florescent lights and electric heater. All was well. The guy on guard duty knocked on our door and asked if he could come inside to warm up and to see what we were doing and so we let him in. There was a cable connecting one of the radios to an antenna that made a "Bzzssszzss.." noise whenever we transmitted and he got curious and touched it with his index finger. "KAPOWWW!" We couldn't do much for his injury. It just appeared as a little white dot on the end of his finger about the size of the lead in a penciil. The next day his finger looked like a puffed up sausage and he couldn't allow anything to touch it. It looked like the skin might split before it got better. Since then I've always tried to contain my curiosity or to investigate with a meter. | ||
| K8QV | 2015-05-26 | |
|---|---|---|
| RE: My Very First RF Burn! | ||
| It is a unique sensation. Not fond of it. Reply to a comment by : W4XKE on 2015-05-26 I was in a communications van on a Dodge M-37 while in the 138th Signal Bn and it was cold outside. We had a generator supplying power to our radios, florescent lights and electric heater. All was well. The guy on guard duty knocked on our door and asked if he could come inside to warm up and to see what we were doing and so we let him in. There was a cable connecting one of the radios to an antenna that made a "Bzzssszzss.." noise whenever we transmitted and he got curious and touched it with his index finger. "KAPOWWW!" We couldn't do much for his injury. It just appeared as a little white dot on the end of his finger about the size of the lead in a penciil. The next day his finger looked like a puffed up sausage and he couldn't allow anything to touch it. It looked like the skin might split before it got better. Since then I've always tried to contain my curiosity or to investigate with a meter. | ||
| W4XKE | 2015-05-26 | |
|---|---|---|
| My Very First RF Burn! | ||
| I was in a communications van on a Dodge M-37 while in the 138th Signal Bn and it was cold outside. We had a generator supplying power to our radios, florescent lights and electric heater. All was well. The guy on guard duty knocked on our door and asked if he could come inside to warm up and to see what we were doing and so we let him in. There was a cable connecting one of the radios to an antenna that made a "Bzzssszzss.." noise whenever we transmitted and he got curious and touched it with his index finger. "KAPOWWW!" We couldn't do much for his injury. It just appeared as a little white dot on the end of his finger about the size of the lead in a penciil. The next day his finger looked like a puffed up sausage and he couldn't allow anything to touch it. It looked like the skin might split before it got better. Since then I've always tried to contain my curiosity or to investigate with a meter. | ||
| K5MF | 2015-05-26 | |
|---|---|---|
| My Very First RF Burn! | ||
| Funny! If you haven't been bit at least a couple of times you aren't trying very hard. My Navy days working on the AN/SPS 48A radar provided some fond and not so fond memories. Lets see, voltages of 3.2 megavolts, steel ship, floating in salt water, 2-near death experiences. What's not to like? This KW stuff is small potatoes. 73, Tom/K5MF | ||
