(OT) - Unplanned Discovery
Locked
 
|
Most people on this Reflector are well educated and intelligent.
Apparently, I'm the exception because this one got by me. I'm only owning up to this in the hope that it might help someone else on the Reflector. For the last couple of years I've been bothered by a high background noise level. It happened on my K1, K2, K3, KX2 and KX3. I attributed this to the fact that my antenna has been in my attic for the last fifteen years and propagation hasn't been good lately. I just got official permission from the HOA to install an end fed wire outside. I was thrilled. I put it up. The darn thing wasn't any better than the attic doublet. Noisy as heck! What a letdown! So I'm laying in bed last night reflecting on how my little KX1 was the only Elecraft radio that never had noise problems and seemed to have a receiver quieter than my K3. Whoa! The KX1 always ran on batteries...could it be????? I just took delivery on a brand new Kx33 Low RFI power supply a couple days ago. It was advertised in the last QST. Previous to that, I've been using a Samlex 1235M. For the heck of it, I connected my K2 to an SLA battery and the noise was still there. But when I disconnected the Kx33 power supply from the wall, the noise level dropped dramatically. Then I switched to the Samlex and the noise came back. Back on the battery, the noise dropped again as long as the power supplies were unplugged and dead. I have a laptop next to the computer. When I pulled the plug on the laptop supply, the rest of the noise went away. I was down to S0/S1 and CW signals were popping out all over the band again. Running the computer on its internal battery did NOT contribute any noise. It was the computer power supply. Now that I am totally on batteries, I also appear to be immune from both the gas furnace and the dishwasher motor both of which caused me problems when using the AC supplies. YES, I HAD CHOKES ON ALL SUPPLIES, CABLES, WIRE. I've been on the air all day with my new outside antenna, on battery power, making contacts near and far and I feel like I've hit the jackpot. Since I'm totally QRP and CW, being limited to batteries is not an issue. If you're going to check your own supplies out, remember they've got to be OFF/UNPLUGGED from the wall. Just disconnecting them from the radio/computer isn't enough. It's RF. 73, Stan WB2LQF 1 ______________________________________________________________ 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] |
|
Administrator
|
Great story, Stan. Now you know why the K3/K3S/KX2/KX3 all have data modes you can use without a computer :)
73, Wayne N6KR > On Nov 19, 2017, at 4:23 PM, stan levandowski <[hidden email]> wrote: > > Most people on this Reflector are well educated and intelligent. Apparently, I'm the exception because this one got by me. I'm only owning up to this in the hope that it might help someone else on the Reflector. > > For the last couple of years I've been bothered by a high background noise level. It happened on my K1, K2, K3, KX2 and KX3. I attributed this to the fact that my antenna has been in my attic for the last fifteen years and propagation hasn't been good lately. > > > I just got official permission from the HOA to install an end fed wire outside. I was thrilled. I put it up. The darn thing wasn't any better than the attic doublet. Noisy as heck! What a letdown! > > > So I'm laying in bed last night reflecting on how my little KX1 was the only Elecraft radio that never had noise problems and seemed to have a receiver quieter than my K3. > > > Whoa! The KX1 always ran on batteries...could it be????? > > > I just took delivery on a brand new Kx33 Low RFI power supply a couple days ago. It was advertised in the last QST. Previous to that, I've been using a Samlex 1235M. For the heck of it, I connected my K2 to an SLA battery and the noise was still there. But when I disconnected the Kx33 power supply from the wall, the noise level dropped dramatically. Then I switched to the Samlex and the noise came back. Back on the battery, the noise dropped again as long as the power supplies were unplugged and dead. > > > I have a laptop next to the computer. When I pulled the plug on the laptop supply, the rest of the noise went away. I was down to S0/S1 and CW signals were popping out all over the band again. Running the computer on its internal battery did NOT contribute any noise. It was the computer power supply. > > > Now that I am totally on batteries, I also appear to be immune from both the gas furnace and the dishwasher motor both of which caused me problems when using the AC supplies. YES, I HAD CHOKES ON ALL SUPPLIES, CABLES, WIRE. > > > I've been on the air all day with my new outside antenna, on battery power, making contacts near and far and I feel like I've hit the jackpot. Since I'm totally QRP and CW, being limited to batteries is not an issue. > > > If you're going to check your own supplies out, remember they've got to be OFF/UNPLUGGED from the wall. Just disconnecting them from the radio/computer isn't enough. It's RF. > > > 73, Stan WB2LQF > > > > > > > 1 > > ______________________________________________________________ > 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) - Unplanned Discovery
|
|
In reply to this post by stan levandowski
Wow.
Going to try that. Thanks for this great post. On Sun, Nov 19, 2017 at 19:23 stan levandowski <[hidden email]> wrote: > Most people on this Reflector are well educated and intelligent. > Apparently, I'm the exception because this one got by me. I'm only > owning up to this in the hope that it might help someone else on the > Reflector. > > For the last couple of years I've been bothered by a high background > noise level. It happened on my K1, K2, K3, KX2 and KX3. I attributed > this to the fact that my antenna has been in my attic for the last > fifteen years and propagation hasn't been good lately. > > > I just got official permission from the HOA to install an end fed wire > outside. I was thrilled. I put it up. The darn thing wasn't any > better than the attic doublet. Noisy as heck! What a letdown! > > > So I'm laying in bed last night reflecting on how my little KX1 was the > only Elecraft radio that never had noise problems and seemed to have a > receiver quieter than my K3. > > > Whoa! The KX1 always ran on batteries...could it be????? > > > I just took delivery on a brand new Kx33 Low RFI power supply a couple > days ago. It was advertised in the last QST. Previous to that, I've > been using a Samlex 1235M. For the heck of it, I connected my K2 to an > SLA battery and the noise was still there. But when I disconnected the > Kx33 power supply from the wall, the noise level dropped dramatically. > Then I switched to the Samlex and the noise came back. Back on the > battery, the noise dropped again as long as the power supplies were > unplugged and dead. > > > I have a laptop next to the computer. When I pulled the plug on the > laptop supply, the rest of the noise went away. I was down to S0/S1 and > CW signals were popping out all over the band again. Running the > computer on its internal battery did NOT contribute any noise. It was > the computer power supply. > > > Now that I am totally on batteries, I also appear to be immune from both > the gas furnace and the dishwasher motor both of which caused me > problems when using the AC supplies. YES, I HAD CHOKES ON ALL SUPPLIES, > CABLES, WIRE. > > > I've been on the air all day with my new outside antenna, on battery > power, making contacts near and far and I feel like I've hit the > jackpot. Since I'm totally QRP and CW, being limited to batteries is > not an issue. > > > If you're going to check your own supplies out, remember they've got to > be OFF/UNPLUGGED from the wall. Just disconnecting them from the > radio/computer isn't enough. It's RF. > > > 73, Stan WB2LQF > > > > > > > 1 > > ______________________________________________________________ > 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] -- --- 72, Rich Hurd / WC3T / DMR: 3142737 PA Army MARS, Northampton County RACES, EPA-ARRL Public Information Officer for Scouting Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) Grid: *FN20is* ______________________________________________________________ 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] |
|
|
I'm really surprised you had an issue with the KX33 supply.
- JT On Sun, Nov 19, 2017 at 7:31 PM, rich hurd WC3T <[hidden email]> wrote: > Wow. > > Going to try that. Thanks for this great post. > > On Sun, Nov 19, 2017 at 19:23 stan levandowski <[hidden email]> wrote: > >> Most people on this Reflector are well educated and intelligent. >> Apparently, I'm the exception because this one got by me. I'm only >> owning up to this in the hope that it might help someone else on the >> Reflector. >> >> For the last couple of years I've been bothered by a high background >> noise level. It happened on my K1, K2, K3, KX2 and KX3. I attributed >> this to the fact that my antenna has been in my attic for the last >> fifteen years and propagation hasn't been good lately. >> >> >> I just got official permission from the HOA to install an end fed wire >> outside. I was thrilled. I put it up. The darn thing wasn't any >> better than the attic doublet. Noisy as heck! What a letdown! >> >> >> So I'm laying in bed last night reflecting on how my little KX1 was the >> only Elecraft radio that never had noise problems and seemed to have a >> receiver quieter than my K3. >> >> >> Whoa! The KX1 always ran on batteries...could it be????? >> >> >> I just took delivery on a brand new Kx33 Low RFI power supply a couple >> days ago. It was advertised in the last QST. Previous to that, I've >> been using a Samlex 1235M. For the heck of it, I connected my K2 to an >> SLA battery and the noise was still there. But when I disconnected the >> Kx33 power supply from the wall, the noise level dropped dramatically. >> Then I switched to the Samlex and the noise came back. Back on the >> battery, the noise dropped again as long as the power supplies were >> unplugged and dead. >> >> >> I have a laptop next to the computer. When I pulled the plug on the >> laptop supply, the rest of the noise went away. I was down to S0/S1 and >> CW signals were popping out all over the band again. Running the >> computer on its internal battery did NOT contribute any noise. It was >> the computer power supply. >> >> >> Now that I am totally on batteries, I also appear to be immune from both >> the gas furnace and the dishwasher motor both of which caused me >> problems when using the AC supplies. YES, I HAD CHOKES ON ALL SUPPLIES, >> CABLES, WIRE. >> >> >> I've been on the air all day with my new outside antenna, on battery >> power, making contacts near and far and I feel like I've hit the >> jackpot. Since I'm totally QRP and CW, being limited to batteries is >> not an issue. >> >> >> If you're going to check your own supplies out, remember they've got to >> be OFF/UNPLUGGED from the wall. Just disconnecting them from the >> radio/computer isn't enough. It's RF. >> >> >> 73, Stan WB2LQF >> >> >> >> >> >> >> 1 >> >> ______________________________________________________________ >> 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] > > -- > --- > 72, > Rich Hurd / WC3T / DMR: 3142737 > PA Army MARS, Northampton County RACES, EPA-ARRL Public Information Officer > for Scouting > Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) Grid: > *FN20is* > ______________________________________________________________ > 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 rich hurd WC3T
Rich,
You just discovered the problem with switching power supplies. I'm unaware of any computer power supply that isn't a switcher, but for most 12 volt needs an analog supply should fix the problem. The only downside that I can see is weight; analog supplies can be a bunch heavier, but they are RF quiet. There some quiet switchers out there. You just need to do some research to discover those. One that is quiet is the Tentec. It is actually an Astron that Tentec did some work on. I think the one Elecraft sells is quiet. Bit, you really need to investigate before buying a switcher. 73, Barry K3NDM ------ Original Message ------ From: "rich hurd WC3T" <[hidden email]> To: "stan levandowski" <[hidden email]> Cc: [hidden email] Sent: 11/19/2017 7:31:48 PM Subject: Re: [Elecraft] (OT) - Unplanned Discovery >Wow. > >Going to try that. Thanks for this great post. > >On Sun, Nov 19, 2017 at 19:23 stan levandowski <[hidden email]> >wrote: > >>Most people on this Reflector are well educated and intelligent. >>Apparently, I'm the exception because this one got by me. I'm only >>owning up to this in the hope that it might help someone else on the >>Reflector. >> >>For the last couple of years I've been bothered by a high background >>noise level. It happened on my K1, K2, K3, KX2 and KX3. I >>attributed >>this to the fact that my antenna has been in my attic for the last >>fifteen years and propagation hasn't been good lately. >> >> >>I just got official permission from the HOA to install an end fed wire >>outside. I was thrilled. I put it up. The darn thing wasn't any >>better than the attic doublet. Noisy as heck! What a letdown! >> >> >>So I'm laying in bed last night reflecting on how my little KX1 was >>the >>only Elecraft radio that never had noise problems and seemed to have a >>receiver quieter than my K3. >> >> >>Whoa! The KX1 always ran on batteries...could it be????? >> >> >>I just took delivery on a brand new Kx33 Low RFI power supply a couple >>days ago. It was advertised in the last QST. Previous to that, I've >>been using a Samlex 1235M. For the heck of it, I connected my K2 to >>an >>SLA battery and the noise was still there. But when I disconnected >>the >>Kx33 power supply from the wall, the noise level dropped dramatically. >>Then I switched to the Samlex and the noise came back. Back on the >>battery, the noise dropped again as long as the power supplies were >>unplugged and dead. >> >> >>I have a laptop next to the computer. When I pulled the plug on the >>laptop supply, the rest of the noise went away. I was down to S0/S1 >>and >>CW signals were popping out all over the band again. Running the >>computer on its internal battery did NOT contribute any noise. It was >>the computer power supply. >> >> >>Now that I am totally on batteries, I also appear to be immune from >>both >>the gas furnace and the dishwasher motor both of which caused me >>problems when using the AC supplies. YES, I HAD CHOKES ON ALL >>SUPPLIES, >>CABLES, WIRE. >> >> >>I've been on the air all day with my new outside antenna, on battery >>power, making contacts near and far and I feel like I've hit the >>jackpot. Since I'm totally QRP and CW, being limited to batteries is >>not an issue. >> >> >>If you're going to check your own supplies out, remember they've got >>to >>be OFF/UNPLUGGED from the wall. Just disconnecting them from the >>radio/computer isn't enough. It's RF. >> >> >>73, Stan WB2LQF >> >> >> >> >> >> >>1 >> >>______________________________________________________________ >>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] > >-- >--- >72, >Rich Hurd / WC3T / DMR: 3142737 >PA Army MARS, Northampton County RACES, EPA-ARRL Public Information >Officer >for Scouting >Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) >Grid: >*FN20is* >______________________________________________________________ >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) - Unplanned Discovery
|
|
In reply to this post by JT Croteau-3
Yeah, me too. I bought it because I thought it would be "super clean"
and really small. But its contribution to my problem was pretty much unarguable: Plug it in and I hear noise. Unplug it and I don't hear noise. The instructions that came with it specifically stated that the Kx33 should be placed the full length of the DC plug/cord away from the transceiver. I did that but it didn't work for me. I tried different outlets around the house too. I put chokes on it. No joy. My post is not a complaint about the Kx33 mfgr, or the Samlex Corporation or anyone else. Maybe it's my transceiver, maybe it's my equipment, maybe it's my utility service.....I'm not qualified to say or knowledgeable to analyze. I simply wanted to suggest to others in the Elecraft family that if they have "noise" it might be right under their nose and worth checking out vs. blaming propagation or the next door neighbor ;-) P.S. - My "noise problem" is about two years old and coincides with the purchase of my first switch mode power supply. I had a perfectly good linear supply made by Astron but I deemed it too big and klutzy and dumped it. Another one of my great decisions.... 73, Stan WB2LQF Nov 19, 2017 at 08:05 PM, JT Croteau wrote: > I'm really surprised you had an issue with the KX33 supply. > > - JT ______________________________________________________________ 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 stan levandowski
Hi Stan,
You're far from the only one, but I've been preaching this for many years. Take a look at this piece that I wrote for National Contest Journal a year or two ago. http://k9yc.com/KillingReceiveNoise.pdf An important first move is to search out and destroy every switching power supply you can find. Chances are there are dozens in your home, and dozens more in the homes of all of your neighbors. 73, Jim K9YC On 11/19/2017 4:23 PM, stan levandowski wrote: > Apparently, I'm the exception because this one got by me. ______________________________________________________________ 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) - Unplanned Discovery
|
|
In reply to this post by Barry K3NDM
Hi Barry,
I wasn't the one who experienced the epiphany; have to lay that at Stan's feet. :) Frankly, it's not a big problem for me. However, it did connect a couple dots in that I was at my brother-in-law's house operating on the battery whilst visiting. I remarked that the noise floor was very low and just attributed it to his QTH. Never connected the fact that perhaps it was just the local noise sources and I should be less concerned about QRM from the neighbors and neighboring rooms, and more about what I was feeding the rig and the other sources in the room. I will now be spending some time rearranging things to try this out and get my noise floor down even further. On Sun, Nov 19, 2017 at 20:39 Barry <[hidden email]> wrote: > Rich, > You just discovered the problem with switching power supplies. I'm > unaware of any computer power supply that isn't a switcher, but for most > 12 volt needs an analog supply should fix the problem. The only downside > that I can see is weight; analog supplies can be a bunch heavier, but > they are RF quiet. > > There some quiet switchers out there. You just need to do some > research to discover those. One that is quiet is the Tentec. It is > actually an Astron that Tentec did some work on. I think the one > Elecraft sells is quiet. Bit, you really need to investigate before > buying a switcher. > > 73, > Barry > K3NDM > > ------ Original Message ------ > From: "rich hurd WC3T" <[hidden email]> > To: "stan levandowski" <[hidden email]> > Cc: [hidden email] > Sent: 11/19/2017 7:31:48 PM > Subject: Re: [Elecraft] (OT) - Unplanned Discovery > > >Wow. > > > >Going to try that. Thanks for this great post. > > > >On Sun, Nov 19, 2017 at 19:23 stan levandowski <[hidden email]> > >wrote: > > > >>Most people on this Reflector are well educated and intelligent. > >>Apparently, I'm the exception because this one got by me. I'm only > >>owning up to this in the hope that it might help someone else on the > >>Reflector. > >> > >>For the last couple of years I've been bothered by a high background > >>noise level. It happened on my K1, K2, K3, KX2 and KX3. I > >>attributed > >>this to the fact that my antenna has been in my attic for the last > >>fifteen years and propagation hasn't been good lately. > >> > >> > >>I just got official permission from the HOA to install an end fed wire > >>outside. I was thrilled. I put it up. The darn thing wasn't any > >>better than the attic doublet. Noisy as heck! What a letdown! > >> > >> > >>So I'm laying in bed last night reflecting on how my little KX1 was > >>the > >>only Elecraft radio that never had noise problems and seemed to have a > >>receiver quieter than my K3. > >> > >> > >>Whoa! The KX1 always ran on batteries...could it be????? > >> > >> > >>I just took delivery on a brand new Kx33 Low RFI power supply a couple > >>days ago. It was advertised in the last QST. Previous to that, I've > >>been using a Samlex 1235M. For the heck of it, I connected my K2 to > >>an > >>SLA battery and the noise was still there. But when I disconnected > >>the > >>Kx33 power supply from the wall, the noise level dropped dramatically. > >>Then I switched to the Samlex and the noise came back. Back on the > >>battery, the noise dropped again as long as the power supplies were > >>unplugged and dead. > >> > >> > >>I have a laptop next to the computer. When I pulled the plug on the > >>laptop supply, the rest of the noise went away. I was down to S0/S1 > >>and > >>CW signals were popping out all over the band again. Running the > >>computer on its internal battery did NOT contribute any noise. It was > >>the computer power supply. > >> > >> > >>Now that I am totally on batteries, I also appear to be immune from > >>both > >>the gas furnace and the dishwasher motor both of which caused me > >>problems when using the AC supplies. YES, I HAD CHOKES ON ALL > >>SUPPLIES, > >>CABLES, WIRE. > >> > >> > >>I've been on the air all day with my new outside antenna, on battery > >>power, making contacts near and far and I feel like I've hit the > >>jackpot. Since I'm totally QRP and CW, being limited to batteries is > >>not an issue. > >> > >> > >>If you're going to check your own supplies out, remember they've got > >>to > >>be OFF/UNPLUGGED from the wall. Just disconnecting them from the > >>radio/computer isn't enough. It's RF. > >> > >> > >>73, Stan WB2LQF > >> > >> > >> > >> > >> > >> > >>1 > >> > >>______________________________________________________________ > >>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] > > > >-- > >--- > >72, > >Rich Hurd / WC3T / DMR: 3142737 > >PA Army MARS, Northampton County RACES, EPA-ARRL Public Information > >Officer > >for Scouting > >Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) > >Grid: > >*FN20is* > >______________________________________________________________ > >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] > > -- 72, Rich Hurd / WC3T / DMR: 3142737 PA Army MARS, Northampton County RACES, EPA-ARRL Public Information Officer for Scouting Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) Grid: *FN20is* ______________________________________________________________ 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) - Unplanned Discovery
|
|
In reply to this post by Barry K3NDM
Don't put all switching power supplies in the same bucket. There are
very good ones that ARE QUIET, and then there are those that generate noise. Just because it has the side or back posted with all types of certifications basically says "they met specs at one time". I have 3 Astron switching supplies that are quiet. I have personally performed conducted and radiated emissions testing on those supplies. However, I've repaired several linear supplies an one switcher where the 3 pin AC ground wire was insulated from the chassis by their beautiful paint job. Those did create issues until the cause was discovered and corrected. 73 Bob, K4TAX On 11/19/2017 7:39 PM, Barry wrote: > Rich, > You just discovered the problem with switching power supplies. I'm > unaware of any computer power supply that isn't a switcher, but for > most 12 volt needs an analog supply should fix the problem. The only > downside that I can see is weight; analog supplies can be a bunch > heavier, but they are RF quiet. > > There some quiet switchers out there. You just need to do some > research to discover those. One that is quiet is the Tentec. It is > actually an Astron that Tentec did some work on. I think the one > Elecraft sells is quiet. Bit, you really need to investigate before > buying a switcher. > > 73, > Barry > K3NDM > > ------ Original Message ------ > From: "rich hurd WC3T" <[hidden email]> > To: "stan levandowski" <[hidden email]> > Cc: [hidden email] > Sent: 11/19/2017 7:31:48 PM > Subject: Re: [Elecraft] (OT) - Unplanned Discovery > >> Wow. >> >> Going to try that. Thanks for this great post. >> >> On Sun, Nov 19, 2017 at 19:23 stan levandowski <[hidden email]> >> wrote: >> >>> Most people on this Reflector are well educated and intelligent. >>> Apparently, I'm the exception because this one got by me. I'm only >>> owning up to this in the hope that it might help someone else on the >>> Reflector. >>> >>> For the last couple of years I've been bothered by a high background >>> noise level. It happened on my K1, K2, K3, KX2 and KX3. I >>> attributed >>> this to the fact that my antenna has been in my attic for the last >>> fifteen years and propagation hasn't been good lately. >>> >>> >>> I just got official permission from the HOA to install an end fed wire >>> outside. I was thrilled. I put it up. The darn thing wasn't any >>> better than the attic doublet. Noisy as heck! What a letdown! >>> >>> >>> So I'm laying in bed last night reflecting on how my little KX1 was the >>> only Elecraft radio that never had noise problems and seemed to have a >>> receiver quieter than my K3. >>> >>> >>> Whoa! The KX1 always ran on batteries...could it be????? >>> >>> >>> I just took delivery on a brand new Kx33 Low RFI power supply a couple >>> days ago. It was advertised in the last QST. Previous to that, I've >>> been using a Samlex 1235M. For the heck of it, I connected my K2 >>> to an >>> SLA battery and the noise was still there. But when I disconnected the >>> Kx33 power supply from the wall, the noise level dropped dramatically. >>> Then I switched to the Samlex and the noise came back. Back on the >>> battery, the noise dropped again as long as the power supplies were >>> unplugged and dead. >>> >>> >>> I have a laptop next to the computer. When I pulled the plug on the >>> laptop supply, the rest of the noise went away. I was down to S0/S1 >>> and >>> CW signals were popping out all over the band again. Running the >>> computer on its internal battery did NOT contribute any noise. It was >>> the computer power supply. >>> >>> >>> Now that I am totally on batteries, I also appear to be immune from >>> both >>> the gas furnace and the dishwasher motor both of which caused me >>> problems when using the AC supplies. YES, I HAD CHOKES ON ALL >>> SUPPLIES, >>> CABLES, WIRE. >>> >>> >>> I've been on the air all day with my new outside antenna, on battery >>> power, making contacts near and far and I feel like I've hit the >>> jackpot. Since I'm totally QRP and CW, being limited to batteries is >>> not an issue. >>> >>> >>> If you're going to check your own supplies out, remember they've got to >>> be OFF/UNPLUGGED from the wall. Just disconnecting them from the >>> radio/computer isn't enough. It's RF. >>> >>> >>> 73, Stan WB2LQF >>> >>> >>> >>> >>> >>> >>> 1 >>> >>> ______________________________________________________________ >>> 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] >> >> -- >> --- >> 72, >> Rich Hurd / WC3T / DMR: 3142737 >> PA Army MARS, Northampton County RACES, EPA-ARRL Public Information >> Officer >> for Scouting >> Latitude: 40.761621 Longitude: -75.288988 (40°45.68' N 75°17.33' W) >> Grid: >> *FN20is* >> ______________________________________________________________ >> 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] |
|
|
Most, if not all of those certifications are for safety, not emissions. Further, I'm not at all convinced that compliance with FCC/CISPR standards ensures no RFI to a ham station. Especially if your interests are weak signal, EME, etc.
73, Josh W6XU Sent from my mobile device > Just because it has the side or back posted with all types of certifications basically says "they met specs at one time". > ______________________________________________________________ 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] |
|
|
Josh,
You are quite correct. The usual CISPR standards limits for many SMPS designs are typically set to 50dBuV across the HF spectrum, that translates to roughly 5/9+17dB. These standards are there to protect your old analog TV and commercial FM radio being messed up not your local Ham operator unfortunately. 73 Matthew VK5ZM On 20 November 2017 at 13:25, Josh <[hidden email]> wrote: > Most, if not all of those certifications are for safety, not emissions. > Further, I'm not at all convinced that compliance with FCC/CISPR standards > ensures no RFI to a ham station. Especially if your interests are weak > signal, EME, etc. > > 73, > Josh W6XU > > Sent from my mobile device > > > Just because it has the side or back posted with all types of > certifications basically says "they met specs at one time". > > > > ______________________________________________________________ > 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) - Unplanned Discovery
|
|
In reply to this post by stan levandowski
I have often wondered if the noise from a switching power supply would vary in intensity or other characteristics as the load changes. For example, during transmitting. In a single transmitter environment the user would probably not notice but in a multi-transmitter or SO2R station one just might.
Changes in noise floor might not always be “phase noise” from the other transmitter — could it be different emissions from a switching power supply under full load? 73, Doug, W7KF http://www.w7kf.com <http://www.w7kf.com/> > On Nov 19, 2017, at 6:42 PM, stan levandowski <[hidden email]> wrote: > > Yeah, me too. I bought it because I thought it would be "super clean" and really small. But its contribution to my problem was pretty much unarguable: Plug it in and I hear noise. Unplug it and I don't hear noise. The instructions that came with it specifically stated that the Kx33 should be placed the full length of the DC plug/cord away from the transceiver. I did that but it didn't work for me. I tried different outlets around the house too. I put chokes on it. No joy. > ______________________________________________________________ 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] |
|
|
Noise can absolutely change with load. At light load the SMPS may enter a pulse skipping mode. Some keep pulse width constant and vary switching frequency with load to effectively change duty cycle. Most (all?) will continuously modulate the switching frequency over a small range to spread out the pulse energy. This makes it much easier to come in under required limits, but also by the time you're looking at harmonics up in our bands it's a big smudge of noise.
73, Josh W6XU Sent from my mobile device > On Nov 20, 2017, at 12:58 PM, Doug Smith <[hidden email]> wrote: > > I have often wondered if the noise from a switching power supply would vary in intensity or other characteristics as the load changes. For example, during transmitting. In a single transmitter environment the user would probably not notice but in a multi-transmitter or SO2R station one just might. > > Changes in noise floor might not always be “phase noise” from the other transmitter — could it be different emissions from a switching power supply under full load? > > 73, > Doug, W7KF > http://www.w7kf.com <http://www.w7kf.com/> > > >> On Nov 19, 2017, at 6:42 PM, stan levandowski <[hidden email]> wrote: >> >> Yeah, me too. I bought it because I thought it would be "super clean" and really small. But its contribution to my problem was pretty much unarguable: Plug it in and I hear noise. Unplug it and I don't hear noise. The instructions that came with it specifically stated that the Kx33 should be placed the full length of the DC plug/cord away from the transceiver. I did that but it didn't work for me. I tried different outlets around the house too. I put chokes on it. No joy. >> ______________________________________________________________ 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 stan levandowski
Just a note to comment on my experiences with RV 'converters'/battery chargers. I've had to put an AC switch in the input line to disable the "converters' noise. That solved the problem but sometimes an adjacent RV will provide me with noise. Gil W7GIL ______________________________________________________________ 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] |
|
|
How much noise from "warts" enters the antenna depends on the antenna. Close
and low antenna will pick up more and high and far will pick up less or nothing. Also, balanced or with a good balun will pick up less than unbalanced or where KX3 is a counterpoise. Ignacy, NO9E -- Sent from: http://elecraft.365791.n2.nabble.com/ ______________________________________________________________ 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 Gil Drynan
I don't RV anymore but when I did my 5th wheel came with a charger made by Todd
Engineering, fortunately now out of business. It was simply awful in terms of RFI. In the analog TV days the RV parked outside the garage would interfere with low-band TV. I replaced it with one made by a local company, IOTA Engineering. https://iotaengineering.com/power.htm I found it to be very quiet. (Although I once moonlighted at another company founded by the same guys as IOTA I have no association with this company other than as a satisfied customer). Wes N7WS On 11/20/2017 7:54 AM, Gil Drynan wrote: > Just a note to comment on my experiences with RV 'converters'/battery > chargers. I've had to put an AC switch in the input line to disable the > "converters' noise. That solved the problem but sometimes an adjacent RV > will provide me with noise. > > > Gil > W7GIL > ______________________________________________________________ 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 |