OT 20M Moving QRM (Video)
Locked
 
|
Does anyone recognize this moving QRM? Last evening 6:30pm. Band is dead. Ambient noise pretty calm. But notice the slowly moving noise bumps on the K3S SVGA display. Might this be weather radar? https://vimeo.com/157616344
David A., KK6DA, LA David Ahrendts [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
|
|
Google "Ionospheric sounder". There are lots of them around the world that
operate 24/7 and this may be one of them. 73 Ken Kopp - K0PP On Mar 3, 2016 11:06 AM, "David Ahrendts" <[hidden email]> wrote: > Does anyone recognize this moving QRM? Last evening 6:30pm. Band is dead. > Ambient noise pretty calm. But notice the slowly moving noise bumps on the > K3S SVGA display. Might this be weather radar? > https://vimeo.com/157616344 > > David A., KK6DA, LA > > > > David Ahrendts [hidden email] > > > > > ______________________________________________________________ > 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 > Message delivered to [hidden email] > 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 Message delivered to [hidden email] |
|
|
In reply to this post by David Ahrendts
On Thu,3/3/2016 10:05 AM, David Ahrendts wrote:
> Does anyone recognize this moving QRM? Last evening 6:30pm. Band is dead. Ambient noise pretty calm. But notice the slowly moving noise bumps on the K3S SVGA display. Might this be weather radar? https://vimeo.com/157616344 Nope. It's a switch-mode power supply, the sort of thing that powers almost anything we buy nowadays -- it's in the wall warts for all sorts equipment, battery chargers, computers, even built into home electronics. 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 Message delivered to [hidden email] |
|
|
In reply to this post by David Ahrendts
Hi,
I do not but I have the exact same sounding QRM, and it is spread out as well... If you ever find out what it is, please let me know... I have had this for years, and always wondered... -- 73's, and thanks, Dave (NK7Z) For software/hardware reviews see: http://www.nk7z.net For MixW support see: https://groups.yahoo.com/neo/groups/mixw/info For SSTV help see: http://groups.yahoo.com/neo/groups/MM-SSTV/info On Thu, 2016-03-03 at 10:05 -0800, David Ahrendts wrote: > Does anyone recognize this moving QRM? Last evening 6:30pm. Band is > dead. Ambient noise pretty calm. But notice the slowly moving noise > bumps on the K3S SVGA display. Might this be weather radar? https:/ > /vimeo.com/157616344 > > David A., KK6DA, LA > > > > David Ahrendts [hidden email] > > > > > ______________________________________________________________ > 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 > Message delivered to [hidden email] 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 Message delivered to [hidden email] |
|
|
In reply to this post by Ken G Kopp
That is not an ionosonde... They are a pure carrier moving at a steady
speed, and they sweep MUCH faster than that. -- 73's, and thanks, Dave (NK7Z) For software/hardware reviews see: http://www.nk7z.net For MixW support see: https://groups.yahoo.com/neo/groups/mixw/info For SSTV help see: http://groups.yahoo.com/neo/groups/MM-SSTV/info On Thu, 2016-03-03 at 11:16 -0700, Ken G Kopp wrote: > Google "Ionospheric sounder". There are lots of them around the > world that > operate 24/7 and this may be one of them. > > 73 > > Ken Kopp - K0PP > On Mar 3, 2016 11:06 AM, "David Ahrendts" <[hidden email]> > wrote: > > > Does anyone recognize this moving QRM? Last evening 6:30pm. Band is > > dead. > > Ambient noise pretty calm. But notice the slowly moving noise bumps > > on the > > K3S SVGA display. Might this be weather radar? > > https://vimeo.com/157616344 > > > > David A., KK6DA, LA > > > > > > > > David Ahrendts [hidden email] > > > > > > > > > > ______________________________________________________________ > > 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 > > Message delivered to [hidden email] > > > ______________________________________________________________ > 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 > Message delivered to [hidden email] 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 Message delivered to [hidden email] |
|
|
In reply to this post by Jim Brown-10
Thank you Jim, I have always thought it might be, but I have never been
able to actually unplug one, and have it go away... There is one in the area, that covers several blocks my self and another ham have been looking for for a few years now... -- 73's, and thanks, Dave (NK7Z) For software/hardware reviews see: http://www.nk7z.net For MixW support see: https://groups.yahoo.com/neo/groups/mixw/info For SSTV help see: http://groups.yahoo.com/neo/groups/MM-SSTV/info On Thu, 2016-03-03 at 10:22 -0800, Jim Brown wrote: > On Thu,3/3/2016 10:05 AM, David Ahrendts wrote: > > Does anyone recognize this moving QRM? Last evening 6:30pm. Band is > > dead. Ambient noise pretty calm. But notice the slowly moving noise > > bumps on the K3S SVGA display. Might this be weather radar? https > > ://vimeo.com/157616344 > > Nope. It's a switch-mode power supply, the sort of thing that powers > almost anything we buy nowadays -- it's in the wall warts for all > sorts > equipment, battery chargers, computers, even built into home > electronics. > > 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 > Message delivered to [hidden email] 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 Message delivered to [hidden email] |
|
|
In reply to this post by NK7Z
I too have this all over the place on the lower bands (80 and 40 mostly) at home. I've always thought it was noise from the Faraday cage my indoor antennas have to be inside of causing it. When I'm /P in the hills outside of of town I never hear this...
73, LS W5QD |
|
|
In reply to this post by NK7Z
I'd guess that the average home has at least a couple of dozen
switch-mode power supplies. 73, Jim K9YC On Thu,3/3/2016 12:18 PM, Dave Cole wrote: > Thank you Jim, I have always thought it might be, but I have never been > able to actually unplug one, and have it go away... There is one in > the area, that covers several blocks my self and another ham have been > looking for for a few years now... > -- ______________________________________________________________ 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 Message delivered to [hidden email] |
|
|
Is there any way to easily determine if a wall wart is a SMPS? Most probably are but are there any that are not?
David K0LUM > On Mar 3, 2016, at 4:39 PM, Jim Brown <[hidden email]> wrote: > > I'd guess that the average home has at least a couple of dozen switch-mode power supplies. > > 73, Jim K9YC > > On Thu,3/3/2016 12:18 PM, Dave Cole wrote: >> Thank you Jim, I have always thought it might be, but I have never been >> able to actually unplug one, and have it go away... There is one in >> the area, that covers several blocks my self and another ham have been >> looking for for a few years now... >> -- > > ______________________________________________________________ > 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 > Message delivered to [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: OT 20M Moving QRM (Video)
|
|
> On Mar 3, 2016, at 5:53 42PM, David Christ <[hidden email]> wrote: > > Is there any way to easily determine if a wall wart is a SMPS? Weigh it. Bud, W2RU ______________________________________________________________ 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 Message delivered to [hidden email] |
|
|
In reply to this post by David Ahrendts
Thanks, everyone, for weighing in. I’m armed with $95 of ferrite snap ons and chokes and two MFJ heavy duty AC filters! Saturday I plan to carefully re-design all of the AC wiring in my office/shack which is, admittedly, a hodgepodge of extension cords and power strips with at least 5 wall warts. I suspect the offending switching PS runs the brand new LG display used with the K3S SVGA. It’s a small, light little thing. Runs very hot. Most likely will be replacing it with a linear wall wart or something cleaner.
I found this article that explains the differences between linear and switching power supplies: http://www.clever4hire.com/special-articles/home/ac-dc-power-supplies---using-wall-warts Will report back. David A., KK6DA > On Mar 3, 2016, at 10:05 AM, David Ahrendts <[hidden email]> wrote: > > Does anyone recognize this moving QRM? Last evening 6:30pm. Band is dead. Ambient noise pretty calm. But notice the slowly moving noise bumps on the K3S SVGA display. Might this be weather radar? https://vimeo.com/157616344 > > David A., KK6DA, LA > > > > David Ahrendts [hidden email] > > > > > ______________________________________________________________ > 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 > Message delivered to [hidden email] David Ahrendts [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
|
|
In reply to this post by W2RU - Bud Hippisley
On Thu,3/3/2016 2:57 PM, W2RU - Bud Hippisley wrote:
>> Is there any way to easily determine if a wall wart is a SMPS? > Weigh it. Yes -- switch-mode supplies are a lot lighter for the same power rating. Another way -- tune a portable AM radio to the high end of the AM band and listen for noise as you hold the ferrite loopstick antenna next to the unit. Linear supplies will be dead quiet, SMPS units will be noisy. I use a Kenwood TH-F6A, which uses a ferrite loopstick in the base below 10 MHz, and I tune it to about 2 MHz. 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 Message delivered to [hidden email] |
|
|
In reply to this post by David Christ
Weigh it. Most small wall warts are also very light. I've got a couple
of heavy larger ones in the junk box and the difference is hard to miss. The cable from it is the radiator of course, a BC band radio tuned to a clear spot [preferably at the high end] will usually show a distinct increase in noise as you move it up the cable. I was choking a 4 A feed to the wireless equipment and used a couple of 3 1/2" OD [or so] toroids that N6XI gave me. Consulting the K9YC recipe, I wound 12 turns of Radio Shack red-black pair on one, and as many turns as I could get in one layer on the other, wired them in series and then stacked them using zip ties. My theory was that the one with lots of turns would get the 160-80 m stuff and the 12 turns would get 40-30-20. They went right at the Chinese RPOJ power supply in the 24 VDC cable. I don't know the mix but I think probably 34 or 43, I think they were part of a group buy by the contest club. My experience with the small clamp-ons has been poor, unless you get several turns of the cable through it, and even then I don't think there's enough permeability in the magnetic circuit to do much. It's pretty hard to find linear wall warts these days. 73, Fred K6DGW - Northern California Contest Club - CU in the Cal QSO Party 1-2 Oct 2016 - www.cqp.org On 3/3/2016 2:53 PM, David Christ wrote: > Is there any way to easily determine if a wall wart is a SMPS? Most > probably are but are there any that are not? > > David K0LUM ______________________________________________________________ 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 Message delivered to [hidden email] |
|
|
On Thu,3/3/2016 4:13 PM, Fred Jensen wrote:
> Weigh it. Most small wall warts are also very light. I've got a > couple of heavy larger ones in the junk box and the difference is hard > to miss. The cable from it is the radiator of course, a BC band radio > tuned to a clear spot [preferably at the high end] will usually show a > distinct increase in noise as you move it up the cable. > > I was choking a 4 A feed to the wireless equipment and used a couple > of 3 1/2" OD [or so] toroids that N6XI gave me. Consulting the K9YC > recipe, I wound 12 turns of Radio Shack red-black pair on one, For the record, ALL zip cord, including the red/black stuff and the glorified zip cord sold as super exotic speaker wire, is TERRIBLE for RFI. Twisted pair is FAR superior, and should always be used in any situation where there is RFI. This has been well known for at least a century -- in the early days of telephony when the only noise source was 50/60 Hz power and telephone wiring often ran on the same poles as power wiring, the only crosstalk prevention was a crossover of the telephone pair at every other pole. > and as many turns as I could get in one layer on the other, wired them > in series and then stacked them using zip ties. My theory was that > the one with lots of turns would get the 160-80 m stuff and the 12 > turns would get 40-30-20. Max possible turns is about right for 160M on #31, 8 turns is about right for 40-30-20. This is for a 2.4-in o.d. toroid. > They went right at the Chinese RPOJ power supply in the 24 VDC cable. > I don't know the mix but I think probably 34 or 43, I think they were > part of a group buy by the contest club. All our group buys have been #31. > > My experience with the small clamp-ons has been poor, unless you get > several turns of the cable through it, and even then I don't think > there's enough permeability in the magnetic circuit to do much. It's > pretty hard to find linear wall warts these days. Right. A choke without enough wound turns is a waste of time and money. BUT inductance is proportional to the length of the cable path through the ferrite, and the clamp-ons are much longer than the toroid, so fewer turns are "right" with clamp-ons as compared to toroids. Roughly half the number of turns is a good rule of thumb. 5 turns is a good starting point for a #31 clamp that's about 1-inch long for 40M - 10M. 2 turns is about right for 6M, with several of these 2-turn cores in series along the coax. I'm currently working on a step-by-step tutorial on chasing noise, and with some detail about different noise sources. First publication will be in the next issue of NCJ. 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 Message delivered to [hidden email] |
|
|
This is DEFINTELY something I'll be ready to read and heed. :)
On 3/4/2016 11:01 AM, Jim Brown wrote: > > I'm currently working on a step-by-step tutorial on chasing noise, and > with some detail about different noise sources. First publication will > be in the next issue of NCJ. > ______________________ Clay Autery, KG5LKV MONTAC Enterprises (318) 518-1389 ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: OT 20M Moving QRM (Video)
|
Banned User
|
Me too. Please let us know when it is available!
Ramon, NQ9V > On Mar 4, 2016, at 12:29 PM, Clay Autery <[hidden email]> wrote: > > This is DEFINTELY something I'll be ready to read and heed. :) > > On 3/4/2016 11:01 AM, Jim Brown wrote: >> >> I'm currently working on a step-by-step tutorial on chasing noise, and >> with some detail about different noise sources. First publication will >> be in the next issue of NCJ. >> > ______________________ > Clay Autery, KG5LKV > MONTAC Enterprises > (318) 518-1389 > > ______________________________________________________________ > 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 > Message delivered to [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
«
Return to Elecraft
|
1 view|%1 views
| Free forum by Nabble | Edit this page |