Correction P3 Noise Gremlins
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I am talking about noise gremlins that move slowly across the P3
I know that it could be generated by a Power Supply but I inadvertently called the P3 a PS. 73, Phil K3TUF ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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On 12/4/2011 11:09 AM, Phil Theis wrote:
> I am talking about noise gremlins that move slowly across the P3 > I know that it could be generated by a Power Supply but I inadvertently > called the P3 a PS. No problem, I knew you meant P3, "S" and "3" are moderately close on the keyboard. Regarding the "noise gremlins": What do they look like? Are they sort of broad-bandish [a technical term]? How fast do the gremlins move? [KHz/sec or something like that] Where do you set your Ref Lvl? What is the Scale setting? Occasionally, I'll see: 1. A group of very narrow noise pulses, not terribly strong, run through the display at maybe 5 or so KHz/sec, usually from high to low frequency. I might have heard them once or twice, generally there's no audio indication. I disconnect my antennas when I'm not using the radio but leaving it on, and I've never seen them then. 2. A more broadband, bump in the reference level runs across the screen, maybe 20-25 KHz/sec, again usually down in frequency but not always. It's definitely some sort of broadbandish signal coming in on the antenna. I've never heard anything as it goes by. I'm about 25 mi from Beale AFB with the PAVE PAWS radar and numerous other electronic systems the USAF never talks about. I'm a bit suspicious, but it's certainly not a problem. 3. Right after P3 build, my baseline would "wander" upwards as if there was an increase in noise in some range on the screen. I heard nothing as this happened. Putting my hand flat on top of the P3 restored the straight baseline. Taking the case apart and shining up the paint-masked places where the screws go and making sure all the screws are tight seems to have fixed it. It seems the entire radio spectrum is suffused with man-made signals of all types. Try listening on 443.920 for awhile. Many of the noises there would get a little boy in trouble if he made them. :-) 73, Fred K6DGW - Northern California Contest Club - CU in the 2012 Cal QSO Party 6-7 Oct 2012 - www.cqp.org ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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It's not coming through your antenna. I see the same thing here in north
Texas, especially if there's not much in the way of received signals and often at power-up. It doesn't seem to matter which band the radio's tuned to. It's definitely some kind of pickup within the P3 box, probably from an internal switching power supply. When it shows up I can move it around and make it come and go by putting some pressure on the top of the enclosure and flexing it a bit. I've always intended to crack the case and see if I could get the noise to appear and maybe fool with cable dress to see if that's the cause. It's not enough of a problem to get me to put it at the top of my agenda. 73... Randy, W8FN > 2. A more broadband, bump in the reference level runs across the > screen, maybe 20-25 KHz/sec, again usually down in frequency but not > always. It's definitely some sort of broadbandish signal coming in on > the antenna. I've never heard anything as it goes by. I'm about 25 mi > from Beale AFB with the PAVE PAWS radar and numerous other electronic > systems the USAF never talks about. I'm a bit suspicious, but it's > certainly not a problem. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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On 12/4/2011 2:15 PM, Randy Farmer wrote:
> When it shows up I can > move it around and make it come and go by putting some pressure on the > top of the enclosure and flexing it a bit. I'm pretty sure we're talking about two different things. The sort of broadband "hump" [maybe 6-10 KHz wide] I see moves all by itself, usually from high to low frequency, and at a very stable, constant rate. It just makes a pass through the screen, and I've never seen it with no antenna. If I'm in a contest and thus on the air fairly steadily, I might see it about once every 90 minutes on average. The PP at Beale AFB is a phased-array radar and looks all over the place in milliseconds. It's not far above sea level, we're at 1,800 feet, and I hear it on 70 cm every now and then. I don't think that's the source of the above, however. As I mentioned, my P3 is somewhat "case-sensitive." Getting good contact at all the screws, and tight screws, seems to be important. The paint masking on mine looked really good, so I skipped the "sand off the paint mask points" instruction. In my defense, it seemed like a good idea at the time. I do wish there was a grounding screw on the back of the P3 that I could bond to my single-point safety ground. Other than that, it is working super and has added several new ones to my DXCC total. 73, Fred K6DGW - Northern California Contest Club - CU in the 2012 Cal QSO Party 6-7 Oct 2012 - www.cqp.org ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: Correction P3 Noise Gremlins
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In reply to this post by k6dgw
On 12/4/2011 1:08 PM, Fred Jensen wrote:
> A group of very narrow noise pulses, not terribly strong, run > through the display at maybe 5 or so KHz/sec, usually from high to low > frequency. I might have heard them once or twice, generally there's no > audio indication. I disconnect my antennas when I'm not using the radio > but leaving it on, and I've never seen them then. Signals like this are quite common here in northern California. I don't know their source, don't know if they are intentionally "signals" .or unintentionally radiated noise. I find that I can often hear this stuff in my headphones. > > 2. A more broadband, bump in the reference level runs across the > screen, maybe 20-25 KHz/sec, again usually down in frequency but not > always. It's definitely some sort of broadbandish signal coming in on > the antenna. I've never heard anything as it goes by. I'm about 25 mi > from Beale AFB with the PAVE PAWS radar and numerous other electronic > systems the USAF never talks about. I'm a bit suspicious, but it's > certainly not a problem. This sounds like typical trash from electronics equipment and their switching power supplies. Can be anything from battery chargers to 12V switching PSUs for low voltage lighting to computers to various microprocessor-based equipment of all sorts. The fact that stuff like this is not audible is largely due to AGC smoothing out the increased noise level when we tune across it. 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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One of the interesting things about having a panadaptor is being able to
"see" rather than just "hear" what's going on in a small spectral region. I see all kinds of things racing across the screen, noise-floor bumps, etc. But, now that I can "see," I'd never willingly give it up. I can find holes in wall-to-wall contest-related signals to plop down and run Qs, I can see activity level in a 50 KHz segment of a band and move from signal to signal instead of slowly tuning through the dead air from one to another. I hope I never get jaded by it :-). Rob K6RB > On 12/4/2011 1:08 PM, Fred Jensen wrote: >> A group of very narrow noise pulses, not terribly strong, run >> through the display at maybe 5 or so KHz/sec, usually from high to low >> frequency. I might have heard them once or twice, generally there's no >> audio indication. I disconnect my antennas when I'm not using the radio >> but leaving it on, and I've never seen them then. > > Signals like this are quite common here in northern California. I don't > know their source, don't know if they are intentionally "signals" .or > unintentionally radiated noise. I find that I can often hear this stuff > in my headphones. > >> >> 2. A more broadband, bump in the reference level runs across the >> screen, maybe 20-25 KHz/sec, again usually down in frequency but not >> always. It's definitely some sort of broadbandish signal coming in on >> the antenna. I've never heard anything as it goes by. I'm about 25 mi >> from Beale AFB with the PAVE PAWS radar and numerous other electronic >> systems the USAF never talks about. I'm a bit suspicious, but it's >> certainly not a problem. > > This sounds like typical trash from electronics equipment and their > switching power supplies. Can be anything from battery chargers to 12V > switching PSUs for low voltage lighting to computers to various > microprocessor-based equipment of all sorts. The fact that stuff like > this is not audible is largely due to AGC smoothing out the increased > noise level when we tune across it. > > 73, Jim K9YC > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: Correction P3 Noise Gremlins
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I have to agree. It's interesting to see how what I formerly thought was 'just QRN' is
sometimes a localized (in frequency) burst of RF. There are all kinds of phenomena that I had no idea existed which have become visible. It's also helpful to identify the stations with key clicks -- maybe I should apply for an OO appointment so I can send notices to these guys! The P3 has added so much to my enjoyment, not to mention my ability to spot and break through pileups. I recently obtained a 23" monitor that I intend to use for the P3 display as soon as the VGA output becomes available. On 12/5/2011 8:49 AM, [hidden email] wrote: > One of the interesting things about having a panadaptor is being able to > "see" rather than just "hear" what's going on in a small spectral region. > I see all kinds of things racing across the screen, noise-floor bumps, > etc. But, now that I can "see," I'd never willingly give it up. I can find > holes in wall-to-wall contest-related signals to plop down and run Qs, I > can see activity level in a 50 KHz segment of a band and move from signal > to signal instead of slowly tuning through the dead air from one to > another. I hope I never get jaded by it :-). > > Rob K6RB > > >> On 12/4/2011 1:08 PM, Fred Jensen wrote: >>> A group of very narrow noise pulses, not terribly strong, run >>> through the display at maybe 5 or so KHz/sec, usually from high to low >>> frequency. I might have heard them once or twice, generally there's no >>> audio indication. I disconnect my antennas when I'm not using the radio >>> but leaving it on, and I've never seen them then. >> Signals like this are quite common here in northern California. I don't >> know their source, don't know if they are intentionally "signals" .or >> unintentionally radiated noise. I find that I can often hear this stuff >> in my headphones. >> >>> 2. A more broadband, bump in the reference level runs across the >>> screen, maybe 20-25 KHz/sec, again usually down in frequency but not >>> always. It's definitely some sort of broadbandish signal coming in on >>> the antenna. I've never heard anything as it goes by. I'm about 25 mi >>> from Beale AFB with the PAVE PAWS radar and numerous other electronic >>> systems the USAF never talks about. I'm a bit suspicious, but it's >>> certainly not a problem. >> This sounds like typical trash from electronics equipment and their >> switching power supplies. Can be anything from battery chargers to 12V >> switching PSUs for low voltage lighting to computers to various >> microprocessor-based equipment of all sorts. The fact that stuff like >> this is not audible is largely due to AGC smoothing out the increased >> noise level when we tune across it. >> >> 73, Jim K9YC >> >> >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[hidden email] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> >> > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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