Topics

Follow up on RF Quiet UPS *** Updated ***

Simon Brown
 

Well,

 

Today I powered the house down quickly, determined that my UPS is the prime source of noise. There’s a small amount from the video cards in my two computers, but it’s that UPS what’s doing it. This coming week I’ll put a few plugs on things and run without the UPS, then eliminate any further noise, then buy a new UPS.

 

Will report back.

 

Also, it’s so very dry here and being next to the cost the insulators on the 11kV feed a few fields away are breaking down, HF is unusable. Will report to the electricity people next week.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike German via Groups.Io
Sent: 24 June 2019 11:30
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Follow up on RF Quiet UPS

 

Hallo Simon,
Back in 2017 you asked the group about recommendations for a quiet UPS.  I'm interested in what you decided on and what your experience has been with it in terms of reliability and and noise.

Mike

Stephen Matthias
 

Your UPS must have a chopper - switching power supply.  I have limited knowledge of electronics.


On Sun, Jul 7, 2019 at 2:08 PM Simon Brown <simon@...> wrote:

Well,

 

Today I powered the house down quickly, determined that my UPS is the prime source of noise. There’s a small amount from the video cards in my two computers, but it’s that UPS what’s doing it. This coming week I’ll put a few plugs on things and run without the UPS, then eliminate any further noise, then buy a new UPS.

 

Will report back.

 

Also, it’s so very dry here and being next to the cost the insulators on the 11kV feed a few fields away are breaking down, HF is unusable. Will report to the electricity people next week.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike German via Groups.Io
Sent: 24 June 2019 11:30
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Follow up on RF Quiet UPS

 

Hallo Simon,
Back in 2017 you asked the group about recommendations for a quiet UPS.  I'm interested in what you decided on and what your experience has been with it in terms of reliability and and noise.

Mike

Simon Brown
 

It does!

 

Chucks out noise through all connected cables, can’t remove the noise so I will replace the UPS.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Stephen Matthias
Sent: 08 July 2019 04:49
To: SDR Console <main@sdr-radio.groups.io>
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***

 

Your UPS must have a chopper - switching power supply.  I have limited knowledge of electronics.

 

On Sun, Jul 7, 2019 at 2:08 PM Simon Brown <simon@...> wrote:

Well,

 

Today I powered the house down quickly, determined that my UPS is the prime source of noise. There’s a small amount from the video cards in my two computers, but it’s that UPS what’s doing it. This coming week I’ll put a few plugs on things and run without the UPS, then eliminate any further noise, then buy a new UPS.

 

Will report back.

 

Also, it’s so very dry here and being next to the cost the insulators on the 11kV feed a few fields away are breaking down, HF is unusable. Will report to the electricity people next week.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike German via Groups.Io
Sent: 24 June 2019 11:30
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Follow up on RF Quiet UPS

 

Hallo Simon,
Back in 2017 you asked the group about recommendations for a quiet UPS.  I'm interested in what you decided on and what your experience has been with it in terms of reliability and and noise.

Mike

Allan Isaacs
 

I did this about 6 months ago Simon, looking for specific noise but found as you did when I turned off the incoming mains supply and armed with a portable radio that the noise level, instead of disappearing got a lot stronger.

I’m just about to buy a UPS for a customer and noticed a new, larger version of my own that now says it has pure sinewave operation and full time EMI/RFI noise suppression.

This is the Powercool Smart UPS 2000VA 1600W. The case style has been changed from the earlier versions and this is a V2.

They are a little over £160 which is excellent for that size.

I’m afraid all UPS equipments use much the same chopper circuitry in their innards, but I guess the closer to a sinewave output the lower will be conducted noise level.

I suppose you could use a beefy isolation transformer in the mains input to the UPS to improve matters further, but I haven’t tried this.

 

Unfortunately the reliability of mains supplies here is poor and mine kicks in quite often.

On one occasion the interruptions came several times one after another and the UPS died. This is an early 1500VA model. I fitted a couple of new transistors and two new batteries and all was well. After a lot of resistance Scottish and Southern paid up £40 to cover the cost of parts.

I always enjoy their response when I suggest the reason for the breakdown in mains in the New Forest is due to it coming all the way from Scotland.

Allan G3PIY


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Simon Brown
Sent: 07 July 2019 19:08
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***

 

Well,

 

Today I powered the house down quickly, determined that my UPS is the prime source of noise. There’s a small amount from the video cards in my two computers, but it’s that UPS what’s doing it. This coming week I’ll put a few plugs on things and run without the UPS, then eliminate any further noise, then buy a new UPS.

 

Will report back.

 

Also, it’s so very dry here and being next to the cost the insulators on the 11kV feed a few fields away are breaking down, HF is unusable. Will report to the electricity people next week.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike German via Groups.Io
Sent: 24 June 2019 11:30
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Follow up on RF Quiet UPS

 

Hallo Simon,
Back in 2017 you asked the group about recommendations for a quiet UPS.  I'm interested in what you decided on and what your experience has been with it in terms of reliability and and noise.

Mike

 

Graeme Zimmer
 

I’m afraid all UPS equipments use much the same chopper circuitry in their innards, but I guess the closer to a sinewave output the lower will be conducted noise level.

Actually no.

The simple square-wave inverters use a relatively low switching speed, so filtering their harmonics is not too difficult.

However the so-called "Sine Wave" inverters use high-frequency Pulse-Width-Modulation switching which is much harder to filter.

Whether or not it is free of radio interference depends entirely on how much effort the designers have gone to. Unless you buy an expensive military grade UPS it will have "consumer grade" filtering.

Unfortunately the domestic EMC regulations have been so watered down by industry lobbyists that they are almost useless from a radio interference perspective.

Much of the imported gear has fake compliance certificates, and there is essentially zero government compliance checking.


..........Zim

Allan Isaacs
 

Hi Zim
Do you know of a 1.5 to 2KVA UPS that uses LF switching?
I would assume it would have a fairly standard mains transformer for battery
charging and the same or much larger transformer for output. Pretty heavy if
a microwave oven transformer runs at 1KVA.
Many years ago there was a plug-in ISA card that could hold up the
motherboard voltages whilst automatically backing up work. I wonder if a
modern version of these is available.
Allan G3PIY

-----Original Message-----
From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf
Of Graeme Zimmer
Sent: 08 July 2019 16:43
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***


I'm afraid all UPS equipments use much the same chopper circuitry in
their innards, but I guess the closer to a sinewave output the lower
will be conducted noise level.

Actually no.

The simple square-wave inverters use a relatively low switching speed,
so filtering their harmonics is not too difficult.

However the so-called "Sine Wave" inverters use high-frequency
Pulse-Width-Modulation switching which is much harder to filter.

Simon Brown
 

Anyway,

 

Did quite some tidying-up of cables.

 

Noise came from:

 

  • UPS, now removed, and
  • NetSDR which was HORRIBLE! It was radiating from the ethernet cable, this requires further investigation.
  • Still got noise coming from somewhere but these changes had made a big difference to 2m / Band II.

 

Toodles,

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via Groups.Io
Sent: 08 July 2019 05:07
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***

 

It does!

 

Chucks out noise through all connected cables, can’t remove the noise so I will replace the UPS.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Stephen Matthias
Sent: 08 July 2019 04:49
To: SDR Console <main@sdr-radio.groups.io>
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***

 

Your UPS must have a chopper - switching power supply.  I have limited knowledge of electronics.

 

On Sun, Jul 7, 2019 at 2:08 PM Simon Brown <simon@...> wrote:

Well,

 

Today I powered the house down quickly, determined that my UPS is the prime source of noise. There’s a small amount from the video cards in my two computers, but it’s that UPS what’s doing it. This coming week I’ll put a few plugs on things and run without the UPS, then eliminate any further noise, then buy a new UPS.

 

Will report back.

 

Also, it’s so very dry here and being next to the cost the insulators on the 11kV feed a few fields away are breaking down, HF is unusable. Will report to the electricity people next week.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Mike German via Groups.Io
Sent: 24 June 2019 11:30
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Follow up on RF Quiet UPS

 

Hallo Simon,
Back in 2017 you asked the group about recommendations for a quiet UPS.  I'm interested in what you decided on and what your experience has been with it in terms of reliability and and noise.

Mike

jdow
 

The APC Matrix 5000 builds a "sine wave" in some three steps so the switching speed is low. Nonetheless it radiates like a summabitch into high HF and even VHF. It would be nice to find a 20 A plus EMI filter to put on the beastie. (And that leaves the solar array which may or may not be "sane" wrt EMI.

Note that the low switching speed merely means the generated noise spikes are closer together.

{^_^}

On 20190708 09:01:59, Allan Isaacs wrote:
Hi Zim
Do you know of a 1.5 to 2KVA UPS that uses LF switching?
I would assume it would have a fairly standard mains transformer for battery
charging and the same or much larger transformer for output. Pretty heavy if
a microwave oven transformer runs at 1KVA.
Many years ago there was a plug-in ISA card that could hold up the
motherboard voltages whilst automatically backing up work. I wonder if a
modern version of these is available.
Allan G3PIY
-----Original Message-----
From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf
Of Graeme Zimmer
Sent: 08 July 2019 16:43
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***

I'm afraid all UPS equipments use much the same chopper circuitry in
their innards, but I guess the closer to a sinewave output the lower
will be conducted noise level.
Actually no.
The simple square-wave inverters use a relatively low switching speed,
so filtering their harmonics is not too difficult.
However the so-called "Sine Wave" inverters use high-frequency
Pulse-Width-Modulation switching which is much harder to filter.

David McAnally
 

One person's solution to "fix" UPS RF noise.


It's too bad manufacturers don't include something like this as a built-in option or model upgrade.  I suspect there's to much liability to put this out as an aftermarket filter modification product.

David M.
WD5M


On Mon, Jul 8, 2019 at 3:31 PM jdow <jdow@...> wrote:
The APC Matrix 5000 builds a "sine wave" in some three steps so the switching
speed is low. Nonetheless it radiates like a summabitch into high HF and even
VHF. It would be nice to find a 20 A plus EMI filter to put on the beastie. (And
that leaves the solar array which may or may not be "sane" wrt EMI.

Note that the low switching speed merely means the generated noise spikes are
closer together.

{^_^}

Oidar
 
Edited

Another completely different and more drastic solution might be to use DC, like this:



As is shown here. Then the UPS can be replaced with a charger and a big string of batteries.

~10 years ago i was on a seminar where one speaker claimed that it would be better to use 350 VDC as household power since most equipment already used switching technology, and these power supplies will happily accept DC instead of AC. DC is obviously a lot easier to store and distribute than AC, and it could challenge the power companies oligopoly as the household energy peaks could be spread out over 24hr, one phase 230VAC 10A supply would be sufficient for the whole house.

My first thought was that he was insane, however it is tested in this project.

//Mats

Gert Gremmen
 

DC also needs 400/12/19/13V down-switchers to obtain low voltages, and its the cabling that emits any

interferences, regardless if  carries DC or AC.

Feeding your shack with battery backed up supplied 12/24/48 V that in turn is charged by solar panels where the charge electronics and battery are in a faraday cage of fine metal mesh with  filters on both IN (solar and mains) and out for 12/24/48 V would give a better solution. Then finally at the load side connect only trusted equipment, preferably with analog supplies. That is quiet a challenge.

Gert


On 9-7-2019 9:25, Oidar wrote:
Another completely and more drastic solution might be to use DC, like this:



As is shown here.

//Mats
-- 
Independent Expert on CE marking 
Harmonised Standards (HAS-) Consultant @ European Commission for RED and EMC
EMC Consultant
Electrical Safety Consultant

Oidar
 

On Tue, Jul 9, 2019 at 09:57 AM, Gert Gremmen wrote:

DC also needs 400/12/19/13V down-switchers to obtain low voltages, and its the cabling that emits any

interferences, regardless if  carries DC or AC.

But it's not the cabling that generates the unwanted emessions, the cabling is only an antenna for it.
The root cause are the low quality (and cheap) power supplies.

//Mats

Allan Isaacs
 

I imagine that all electrical equipment in that not-so-Smart building would end up by generating RF, not to mention the controller handling the solar panel output.

The only saving in each item would be the mains rectifier and smoothing capacitor and a shock from that distributed 400VDC might be lethal.

 

Pure sine wave output from a UPS. If you’d like to see how this is done in a very expensive UPS read this link.

It does go some way into explaining the power level associated with RF noise.

http://www.radiomuseum.co.uk/KDC3000.html

 

RF noise is not new….I remember many years ago, in the days before switching power supplies, dealing with Tempest requirements.

Using a battery powered TV set some 50 feet away in the road outside the research labs you could tune the TV to an RF noise peak at say 50MHz and resolve a picture from a VDU operating in the building. At the time, our boss had let some programmers get involved with the design of some equipment for NATO and they had employed a young electronics engineer to design the circuitry (not me). The equipment was to be designed to meet Tempest requirements and it failed miserably.

Alas the programmers had seen the word Tempest and made the equipment waterproof.

 

Allan G3PIY

 


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Gert Gremmen
Sent: 09 July 2019 08:57
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***

 

DC also needs 400/12/19/13V down-switchers to obtain low voltages, and its the cabling that emits any

interferences, regardless if  carries DC or AC.

Feeding your shack with battery backed up supplied 12/24/48 V that in turn is charged by solar panels where the charge electronics and battery are in a faraday cage of fine metal mesh with  filters on both IN (solar and mains) and out for 12/24/48 V would give a better solution. Then finally at the load side connect only trusted equipment, preferably with analog supplies. That is quiet a challenge.

Gert

 

On 9-7-2019 9:25, Oidar wrote:

Another completely and more drastic solution might be to use DC, like this:



As is shown here.

//Mats

-- 
Independent Expert on CE marking 
Harmonised Standards (HAS-) Consultant @ European Commission for RED and EMC
EMC Consultant
Electrical Safety Consultant

 

Brendan Wahl
 

Tempest requires water-proofing? Damn, all that Tempest-level gear I used 40 years ago was fake then...

{A former Tempest-boat anchor operator here...}

Troy - K4JDA
 

Sooo ... any recommendations on a UPS?  I need to buy one.  Looking at these two:

APC Sine Wave UPS Battery Backup & Surge Protector, 1500VA, APC Back-UPS Pro (BR1500MS) https://www.amazon.com/dp/B0779LDRWZ/ref=cm_sw_r_cp_api_i_KW1LDbZJ80J71

CyberPower CP1500PFCLCD PFC Sinewave UPS System, 1500VA/900W, 10 Outlets, AVR, Mini-Tower https://www.amazon.com/dp/B00429N19W/ref=cm_sw_r_cp_api_i_tX1LDb9JGZJS6

Allan Isaacs
 

Look at this one Troy. There’s probably a US supplier if you’re an ex-colonial?

I bought one a few months ago for a customer. More battery capacity.

Allan G3PIY

 

https://www.cclonline.com/product/222331/PC-2000VA-V2/UPS-Battery-Backup/Powercool-Smart-UPS-2000VA-2-x-UK-Plug-4-x-IEC-RJ45-x-2-USB-LCD-Display/UPS0254/?gclid=EAIaIQobChMI1ZnipaiP5AIVw4XVCh1SiwBEEAQYAiABEgKlS_D_BwE

 


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of Troy Davis
Sent: 04 October 2019 15:51
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Follow up on RF Quiet UPS *** Updated ***

 

Sooo ... any recommendations on a UPS?  I need to buy one.  Looking at these two:

APC Sine Wave UPS Battery Backup & Surge Protector, 1500VA, APC Back-UPS Pro (BR1500MS) https://www.amazon.com/dp/B0779LDRWZ/ref=cm_sw_r_cp_api_i_KW1LDbZJ80J71

CyberPower CP1500PFCLCD PFC Sinewave UPS System, 1500VA/900W, 10 Outlets, AVR, Mini-Tower https://www.amazon.com/dp/B00429N19W/ref=cm_sw_r_cp_api_i_tX1LDb9JGZJS6

_._,_._,_

 

JAP
 

RFI filter is a good idea. I have myself installed RFI filter before and after my UPS.

Jean.