Noise on your Radio! (
Vložit
- čas přidán 25. 06. 2024
- This is part 1 of 2 of a presentation I made to the Rochester Amateur Radio Association (RaRa) on 3 June 2020 on the subject of noise (QRN) and what can be done about it. It's a nice survey of noise sources. Ask Dave #291 will cover the second half of the presentation.
Subscribe: / davecasler . Ask Dave Playlist: goo.gl/inaQeB. Tip Jar: ke0og.net/tip-jar
To learn more about me, visit: www.dcasler.com/about/
Tip jar (on my website): www.dcasler.com/tip-jar/ (provides a method to use your credit card via PayPal, Also describes Patreon)
To pose an Ask Dave question: www.dcasler.com/ask-dave/ or www.ke0og.net/ask-dave/
To order the most recent and up-to-date Amateur Extra videos on a thumb drive: dcasler.com/aevids-on-stick/
Theme music is "Sour Tennessee Red," by John Deley and the 41 Players, courtesy CZcams Music Library.
I use drawings from OpenClipArt.org, including the "walking man"
Technician training videos, see www.ke0og.net/training/
General training videos, see www.ke0og.net/general/
Amateur Extra training videos, see www.ke0og.net/extra/
List of the Ask Dave videos, see dcasler.com/ask-dave/#askdavelist
Thanks to my sweet wife, Loretta, KBØVWW, for both audio and video assistance! (Her website is www.aldea-art.com.)
My primary website: www.dcasler.com
The ham radio part of my website (direct link): www.ke0og.net
My publishing website: www.mtsneffelspress.com, where you can find my fantasy and science fiction books, as well as some local history books I publish for the Ridgway Railroad Museum and the Ouray County Historical Society
My Amazon author page, which lists my print and Kindle books: www.amazon.com/-/e/B00471I0Q4.
I'm often asked what equipment I use to create the videos. The devices include the Panasonic DMC-G7 camera, Panasonic HDC-TM90 video camera, GoPro Hero2 HD camera, Tascam DR-05 audio recorder, Audio-Technica ATR-3350 lapel microphone, Sony Cyber-shot DSC-W560 digital camera, the Kodak Zi-8 video camera, my iPhone 5S. Software used: CyberLink PowerDirector 17 on an HP Gaming Pavilion, also using Smoothdraw 4.0.5.0, FastStone Image Viewer 5.3, FastStone Capture 8.0, Audacity 2.1.1, LibreOffice 5.0.4.2, and Ink2Go 1.7.2. You can see how my studio is set up by viewing • Tips for Making Instru... .
Twitter: @dcasler - Věda a technologie
Great Dave. Number 290. Another milestone and I've been waiting. Thank you and get back in the air (flying!)
Very well done Dave, thank you, I learned a few new things.
Excellent presentation. 👍
Sounds like perfect audio level and quality. Like the good ole days.
Great presentation, Dave. I enjoyed it.
Not be be confused with the Dutch Rara! Most interesting information for a beginner like myself. Thanks!
Great video. Can't wait for part 2. 73's Clark KG7LOI
Part one was good and I'm looking forward to the next one, Thank You 👌
Thanks again for an informative and useful presentation.
Hello Dave! Thanks for delivering this wonderfully informative presentation to my radio club in Rochester! Everyone in the group had very positive feedback. As usual, you are always there with all the answers! 😁
I haven't got a ham rig, nor do I plan on getting one anytime soon. But I really enjoy listening to you, very interesting and informative channel Sir. I do own a CB though. 👍
Great job!
Very informative!
My mother-in-law emits noise.
grounding of my radio station was or might have been the thing that saved my two big radios and also they were un hooked. it still amused me the path the lighting strike took.
Good information Dave
Thanks Dave for this presentation.you have answered a lot of my questions. 73's G1VJG
The 40-meter or 7-MHz band is an amateur radio frequency band, spanning 7.000-7.300 MHz in ITU Region 2, and 7.000-7.200 MHz in Regions 1 & 3. It's been a while since Region 1&3 were at 7.000 to 7.100.
Thanks Dave DE NX2O Rochester NY
a good noise blanker works very well on impulse noise coming from the electrical utilities
The biggest problem with FT8 is people not staying in their lanes. I often find people not on clean 50hz segments. They split segments leaving lanes unopen for others. Then there are the people that haven't figured out that they shouldn't crowd a segment. FT8 was designed to put a LOT of people in a small segment of RF, but sadly, many haven't figured out how to do that.
City buses aproaching my apartment or driving past were creating a lot of noise for me where I lived a few months ago.
Dave, I currently live in Okinawa, Japan. We are right in the middle of OTH radar Hell. Several countries operate these radars for military use and ocean wave surveillance. They don't work the old way. If you look at one of the signals you will see many equally spaced carriers (say every 500 Hz) across a wide band. They are very powerful signals. They tend to turn on exactly on the minute and run for a predictable period of time and then shut down. They love to operate on the ham bands since we are powerless. You can't run the AGC in the presence of these signals. But if you turn off AGC and cut back the gain you can run QSO's in between the carriers or in the quiet periods. WSPR, FT8, and other weak signal modes can get through. We also have to contend with a lot of military digital HF modes that seem to operate wherever they want. I use an MFJ-1026 noise canceller to help deal with this environment. It works well enough that I can hear WWVH by canceling (nulling) BPM (The closer Chinese Time Standard Stations). de Rich JS6TRQ / WC8J
In region 1 40m is from 7.0 to 7.2 (but some old broadcast stations still appears illegally or by mistake in 7.1-7.2). I hear once a broadcast station on 7.205 shifting to 7.200 and interfering with DX traffic).
Can't wait for the next one, Dave! De WL0JF
This is exactly the video I was hoping for. I just passed my Extra exam the other day along with the technician and general at the same time. So on paper I'm supposed to know what I'm doing but, of course, I don't. And living in NYC there is nothing but noise most of the time, which is compounded by my lack of experience. This helped fill that knowledge gap. Thanks for another great video.
Congratulations on your test results! Good luck with your station setup.
@@davecasler Thanks very much. It's a little like getting a pass to ride the roller coaster and, when you get in, finding out that you have to build it first !
Congrats on the Hat Trick. de N1JLK
@@reganapparel Thanks very much
@@incaroads001 But building it is part of the fun ;-)
After considerable research and experimentation, for me, I have found that massive grounding is over-rated as a solution for RF and noise in general. Normal grounding can be helpful.
It really depends on how good a ground you can get and what type of noise you are dealing with. I once traced a strong noise source to a water pipe. It was generated by the large motor controllers on the city water pumping station and was surprisingly broadband. We almost completely eliminated it by grounding and adding a large RF choke to the outside of the pipe. Grounding is no panacea but it can work wonders in the right situation.
Great insight, David. This will help many. I appreciate your efforts here. There are some situations we cannot correct on our own. I was recently forced to move into an Apartment. I became frustrated and sold off my gear. Flex 5000, FT-950, etc. due to noise I cannot combat. I tracked the noise to the local phone company equipment, and after opening three trouble tickets, which were all closed or lost, without anything being done, I will be contacting Laura Smith next. I kept explaining to the utility, they need to take this seriously. Most I spoke with had no idea what the term RFI meant. I even spoke with an engineer, still no go. Generally, utilities will work to correct issues. Not in this case. S9 + 10 frying type noise all across HF. So bad, it is radiating in the wiring indoors but only on some circuits.
I now operate portable in remote places of Western Washington. Hey, at least I am in the wilderness a bit. :) I surely miss my antenna farm!
Love the Model M. My favorite keyboard to date.
As my fingers get older, they don't work as well on laptop keys. But the Model M just keeps on click'n away!
@@davecasler The Buckling Spring actuation mechanism is VERY hard to beat.
Thanks Dave some very interesting content there mate. Learned a few things so thanks. 73 de 2E0LIG Nathan
I was once operating on a military vhf network, which in the UK is shared with the 4 metre ham band, when an amateur came up on our crystal controlled frequency (we had 10 channels). We had about 20 stations in the network using 6 element yagis. He was asked politely to change frequency and refused. I spoke with my senior officer and asked permission to get him to move. I reminded the ham of the terms of his licence, informing him that he was being ordered to move by a government station. He still refused to move. So I ordered all the net to DF him, then gave the order: "On my mark 1kHz test tone, transmit." He moved. Our transmitters were 100W AM.
Wow. Intentional interference with public safety communications in the USA can land you in jail.
Question: Dave - One thing I did not see mentioned is induced voltage from power lines. I am currently seeing a 60 cycle as measured by oscilloscope. If I am reading the meter correctly it is at about 200V p-p. This is from a disconnected OFDP antenna and about 65 ft of high quality coax. There is some repeated noise on the sine wave, but I think my first task should be to eliminate the sine wave. The reason I think the problem is induction is the long side passes under power lines, near a transformer, and over an in-ground high tension junction box. Not ideal, but this is the room I have. The short leg is totally on my roof, and parallel to the power lines. MFJ recommended a 1:1 choke or an air balun. You recommended previously that I add a 1:1 choke. I tightly coiled up about 19 feet of coax and added it to the MFJ-2010, and that seems to have helped the noise, but not the 60 hz. I am awaiting an MFJ-915 balun. I am beginning to wonder if there is something wrong with my MFJ-2010 which shows a full short from the center to the shielding. Is this normal? Is 60 cycle what they call common mode? Is induction normal? Do you expect the balun to do the job? Do you have additional suggestions? Getting very little of anything intelligible on my radio.
Mark - N5PRD Houston
Currently dealing with line noise on 2m. The utility company came out and bonded 2 guy wires to their pole. Of course this didn’t help. So now I have to somehow put my foot on them. I can jiggle the guy wire and it goes away. No aurora spotted.
Kick the pole, static crash? Let them know your next call will be to the FCC unless they can show you their broadcasting license. FCC takes that stuff serious and will fine them if they do not correct it. I have had pleasant conversations with Laura Smith on this topic. Power company did not want to help because the line in question was 300 feet down on old easement that had grown all sorts of trees and brush. They could not get trucks in there. A letter from her had a ten man crew out cutting trees in a few days. Then bucket crews worked a week. They replaced all of the insulators and my troubles went away. From S9 to S1. Of course, this was many months after my first contact with the utility. I imagine that operation cost plenty. Those trees where 20+ feet tall in there. Although it is rare power lines will cause issue at 100+ MHz. I find that interesting. Is there Internet service over Power line in that area?
I have an icom 2730a powered up with a comet antenna. No static in the background. But my btech 25x2 is constant. Wth.. kk7juj 73?
When your house was hit by lightning did you have the best ground in the neighborhood? I've never understood why hams think they need an awesome ground. Electricity follows the path of least resistance. You only need the one ground rod that services your house and you should hope your neighbor's is a little better than yours. If you have 3 or 10 ground rods and have a super ground where do you think the lightning is going to go.
Jeff ke4fwe
This is a bit misleading. Lighting works in tandem with Ions. It is solely about positive vs. negative ions. Antennas create ions. They stream them skyward, like a raised arm saying "Pick me!!". They also can build up static charges, which creates lightning on a micro scale. Another reason for good grounding.
I kindly suggest some study on this topic.
@@tahoma6889 most damage is caused by lightning hitting utilities which then follows the path of least resistance right thru your shack.
by the way I learn a lot from you videos nose is and interesting subject..
I did learn some things that I would say noise is another mode of entertainment
7.310 i hear Bucharest Romania on SDR UNO
I just found out my massive noise problem WAS coming from my Direct TV equipment. I went from an S9 down to S4 noise level after dropping Direct TV. I never thought to look at there junk. Carl AB1ZI
We have the same problem with a Comcast modem. I wrapped ours in foil which reduced the noise from S9 to about S3 on 2 meters.
@@kd5you1 Place some beads on the cables!
Outstanding session Dave, thanks so much for all the relevant information. It would be even better if you can record some sample noises that impact us by category. I hear many of these but have no idea what they are! For example, one that I hear often on 40M is what I call a 'slow rise of pink noise" ... a mix of lower frequency noise that is gradually rising up the spectrum. Someone told me it could be CATV interference but I have no idea. Thanks, Greg KJ6ER Silicon Valley
The ARRL has some sample noises at www.arrl.org/sounds-of-rfi
I will send in a sample!
For a fraction of a millisecond lightning even produces gamma rays, called TGF's; they disrupt the entire EM spectrum.
science.sciencemag.org/content/367/6474/183
always check for noise and the level of it befofe you spend big on hf it happened to me could not get rid of it it was the solar panels in the close were I live over s9 level gave up at the end just hiting brick walls and the firms who installed them
I know what you are talking about being struck by it. my mate was looking into my radio room when it struck. My loss was not really bad. I lost and old drake receiver. am only. and I lost a free play radio. it actually smoked it. the antenna that it was a g five r v. it tore down the ladder line. any how the flash in my radio room was very bright to the eye. but lets get to the noise. I was in the living room when it happened. the sound sounded like my mates grandson setting off his black powder gun . it was a real loud noise. any how other than frying that little radio. then it traveled to the living room and fried my mates tower. it by passed the brand new fifty five inch television . it was fine. both of my ham radios were spared. it did not get my 706 and my five ninety ken wood.
Great video, TNX for the upload !
73 N8AUM
Thank you. K0mxe
ignition noise is not rare it exists in most new vehicles
Excellent!
73
wd4dda
Another culprit to look out for is, High Refresh Gaming/Computer Monitors👎
dave tree limbs in power lines .... over year fighting them
Im a CB amateur in Europa. PLC adapters from China are killing the HF band here in Europe. These devices make S9+ noise on the 11 meter band and several amateur bands. Some of these PLC adapters have low pass filters making less noise the amateur bands but, when you use a high gain antenne these filters aren't efficient. I know people who gave up their hobby because of these adapters. Another source of noise are solar panels. Its a sad sad sad situation and authorities don't do anything about it.
Good morning Dave : this is about my message I had left you on your antenna video about say 4 weeks back [[I had ask Dave to help me with these 5 antenna problems and you never bothered to reply back to me NO NO
I am now upset with you England London UK N11