Forums

RF Quiet Wall warts

Started by Martin Riddle August 24, 2017
It's been a year or two since I listend to AM Radio, and in that time
theres a new Roku box and linksys router.  Well, I couldn't hear
anything  on the AM band when I checked a week ago. So the quest was
to find the culprits. Its these SMPS wall warts, they literly wipe out
the entire AM band, and also some chinese LED lights( 15w equiv
Grimaldi's ).
Tossing the led lights are easy, the wall warts not so.
I found the old DSL modem transformer wall wart and that is quiet.
Perusing the Innernet, I see some mention Apple supplies and the
Powerstream SMPS supplies are quiet too, any one here with experiance
with them? 

Cheers
Martin Riddle <martin_ridd@verizon.net> wrote:

> It's been a year or two since I listend to AM Radio, and in that time > theres a new Roku box and linksys router. Well, I couldn't hear > anything on the AM band when I checked a week ago. So the quest was > to find the culprits. Its these SMPS wall warts, they literly wipe out > the entire AM band, and also some chinese LED lights( 15w equiv > Grimaldi's ). > Tossing the led lights are easy, the wall warts not so. > I found the old DSL modem transformer wall wart and that is quiet. > Perusing the Innernet, I see some mention Apple supplies and the > Powerstream SMPS supplies are quiet too, any one here with experiance > with them?
> Cheers
Same problem here, except we have flourescent lights with solid-state ballasts, and the line noise is something to behold. The noise blankets everything up to about 10MHz. The only solution here is to take the radio 100 yards out in the middle of a field. There is still a lot of noise, but at least you can pick up some stations. I bought a very nice synthesized receiver to listen to the ham and broadcast bands. To my dismay, I found that most of the shortwave stations have shut down, since they have switched to the internet. About the only ones still operating were the religious nuts trying to get donations. The ham bands were down a lot also. I guess the old guys have died off, and amateur radio doesn't have the same appeal as google. Electronics seems to be following the same route as the vacuum tube. But there are very active local clubs into Arduinos and robotics, so there is some hope for the future.
On Friday, 25 August 2017 02:54:36 UTC+1, Steve Wilson  wrote:
> Martin Riddle <martin_ridd@verizon.net> wrote: > > > It's been a year or two since I listend to AM Radio, and in that time > > theres a new Roku box and linksys router. Well, I couldn't hear > > anything on the AM band when I checked a week ago. So the quest was > > to find the culprits. Its these SMPS wall warts, they literly wipe out > > the entire AM band, and also some chinese LED lights( 15w equiv > > Grimaldi's ). > > Tossing the led lights are easy, the wall warts not so. > > I found the old DSL modem transformer wall wart and that is quiet. > > Perusing the Innernet, I see some mention Apple supplies and the > > Powerstream SMPS supplies are quiet too, any one here with experiance > > with them? > > > Cheers > > Same problem here, except we have flourescent lights with solid-state > ballasts, and the line noise is something to behold. The noise blankets > everything up to about 10MHz. The only solution here is to take the radio > 100 yards out in the middle of a field. There is still a lot of noise, but > at least you can pick up some stations. > > I bought a very nice synthesized receiver to listen to the ham and > broadcast bands. To my dismay, I found that most of the shortwave stations > have shut down, since they have switched to the internet. About the only > ones still operating were the religious nuts trying to get donations. The > ham bands were down a lot also. I guess the old guys have died off, and > amateur radio doesn't have the same appeal as google. > > Electronics seems to be following the same route as the vacuum tube. But > there are very active local clubs into Arduinos and robotics, so there is > some hope for the future.
Short wave had its day. It was a hard way to do a fraction of what the net does now. AM ie MW/LW likewise really. The only thing of interest on SW was the nutty & the politically iffy stations, now we got 1000s times as many online. Has the OP set up a big outdoor aerial? NT
tabb...@gmail.com wrote:

----------------------------
> > > Short wave had its day. It was a hard way to do a fraction of what the > net does now. AM ie MW/LW likewise really. The only thing of interest > on SW was the nutty & the politically iffy stations, now we got 1000s > times as many online. >
** SW was ( still is ?) heavily used for news and propaganda - anyone with a modest SW receiver could listen to the megawatt stations. Such listening was ( is still ? ) illegal within many totalitarian regimes and transmissions were jammed where possible. I understand China and North Korea heavily censor the internet - but what happens with SW these days ? .... Phil
Steve Wilson <no@spam.com> wrote:
> I bought a very nice synthesized receiver to listen to the ham and > broadcast bands. To my dismay, I found that most of the shortwave stations > have shut down, since they have switched to the internet. About the only > ones still operating were the religious nuts trying to get donations. The > ham bands were down a lot also. I guess the old guys have died off, and > amateur radio doesn't have the same appeal as google.
This is also the reason why nobody cares about the interference from wall warts. The AM (HF) bands are no longer used by the public. Besides, there is interference from almost any technology in use today, not only switched-mode power supplies. There is ethernet over powerline, DSL, wireless charging, RFID, and the list goes on and on. It is better to throw the towel and give up on receiving AM.
Rob wrote:

-------------

> > This is also the reason why nobody cares about the interference from > wall warts. The AM (HF) bands are no longer used by the public. >
** Some still do, anyone more than 25 yards from a SMPS or dodgy WW.
> Besides, there is interference from almost any technology in use today, > not only switched-mode power supplies. There is ethernet over powerline, > DSL, wireless charging, RFID, and the list goes on and on. >
** No, fools like you go on and on.
> It is better to throw the towel and give up on receiving AM.
** Absurd bollocks. .... Phil
On Thursday, August 24, 2017 at 9:35:20 PM UTC-4, Martin Riddle wrote:
> It's been a year or two since I listend to AM Radio, and in that time > theres a new Roku box and linksys router. Well, I couldn't hear > anything on the AM band when I checked a week ago. So the quest was > to find the culprits. Its these SMPS wall warts, they literly wipe out > the entire AM band, and also some chinese LED lights( 15w equiv > Grimaldi's ). > Tossing the led lights are easy, the wall warts not so. > I found the old DSL modem transformer wall wart and that is quiet. > Perusing the Innernet, I see some mention Apple supplies and the > Powerstream SMPS supplies are quiet too, any one here with experiance > with them? > > Cheers
Do you know if the interference is radiated or conducted? (Tin foil hat (copper tape) for one, a ferrite choke thing for the other?) George H.
On Fri, 25 Aug 2017 01:54:28 GMT, Steve Wilson <no@spam.com> wrote:

>Martin Riddle <martin_ridd@verizon.net> wrote: > >> It's been a year or two since I listend to AM Radio, and in that time >> theres a new Roku box and linksys router. Well, I couldn't hear >> anything on the AM band when I checked a week ago. So the quest was >> to find the culprits. Its these SMPS wall warts, they literly wipe out >> the entire AM band, and also some chinese LED lights( 15w equiv >> Grimaldi's ). >> Tossing the led lights are easy, the wall warts not so. >> I found the old DSL modem transformer wall wart and that is quiet.
Most likely DSL supply was an old style iron core transformer operating on 50 or 60 Hz. These iron core wall warts are heavier than the SMPS wall warts, so a quick check is easy to do, Just replace the noisy SMPS with an iron core wall wart. Check the output voltage and is it AC or DC and get a similar iron core model. It doesn't have to be a wall wart, one with a mains core works OK.
>> Perusing the Innernet, I see some mention Apple supplies and the >> Powerstream SMPS supplies are quiet too, any one here with experiance >> with them? > >> Cheers > >Same problem here, except we have flourescent lights with solid-state >ballasts, and the line noise is something to behold. The noise blankets >everything up to about 10MHz. The only solution here is to take the radio >100 yards out in the middle of a field. There is still a lot of noise, but >at least you can pick up some stations.
The same problem all over the world in urban areas. For this reason, some hams use a remote controlled receiver at their (quiet) summer cottage and transfer the received audio over the internet to their apartment. Some also have remote controlled transmitters at the summer cottage. An other alternative is to use some shared wide band receivers to tune in individual stations over the net. Take a look at http://www.websdr.org/
> >I bought a very nice synthesized receiver to listen to the ham and >broadcast bands. To my dismay, I found that most of the shortwave stations >have shut down, since they have switched to the internet. About the only >ones still operating were the religious nuts trying to get donations.
There are still some news and/or propaganda stations.
>The >ham bands were down a lot also. I guess the old guys have died off, and >amateur radio doesn't have the same appeal as google.
The number of CW or SSB speech transmissions has dropped drastically. A large group has moved to various digital modes. Check the waterfall display of a ham band to see the number of digital transmissions.
> >Electronics seems to be following the same route as the vacuum tube. But >there are very active local clubs into Arduinos and robotics, so there is >some hope for the future.
On Fri, 25 Aug 2017 06:25:49 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

>On Thursday, August 24, 2017 at 9:35:20 PM UTC-4, Martin Riddle wrote: >> It's been a year or two since I listend to AM Radio, and in that time >> theres a new Roku box and linksys router. Well, I couldn't hear >> anything on the AM band when I checked a week ago. So the quest was >> to find the culprits. Its these SMPS wall warts, they literly wipe out >> the entire AM band, and also some chinese LED lights( 15w equiv >> Grimaldi's ). >> Tossing the led lights are easy, the wall warts not so. >> I found the old DSL modem transformer wall wart and that is quiet. >> Perusing the Innernet, I see some mention Apple supplies and the >> Powerstream SMPS supplies are quiet too, any one here with experiance >> with them? >> >> Cheers > >Do you know if the interference is radiated or conducted? >(Tin foil hat (copper tape) for one, a ferrite choke thing for the >other?) > >George H.
Probably Conducted=> then radiated by the power lines. The Favorite Fairite Bead does very little on the DC output lead. I could try an Isobar power tap, to see. I have a Netgear Gbit switch that the smps Wall wart is pretty quiet in comparision. As well as a Logitech speake rsmps wallwart. Cheers Cheers
Phil Allison <pallison49@gmail.com> wrote:
>> Besides, there is interference from almost any technology in use today, >> not only switched-mode power supplies. There is ethernet over powerline, >> DSL, wireless charging, RFID, and the list goes on and on. >> > > ** No, fools like you go on and on.
You are welcome to stick your head in the sand! I am a radio amateur myself, but fortunately only active on VHF/UHF/SHF. The HF amateurs are complaining all the time about those technologies and trying to get them abolished so they can continue their hobby, but realistically it is just a very small group compared to users of modern technology.