I have found some LEDs are noisy around HIFI gear

Various LED light bulbs and even smaller LEDs on portable Hard Drives

I can pick them up on FM radio, also various switch mode power supplies can wipe out the radio.

I was wondering if there are any standards for computers, wifi modems, switch mode power supplies and LEDs for producing noise

Maybe give all products a noise rating like the 5 star energy rating system.

Create a 5 star rated noise standard and apply it to all electronic devices.

I’d like to be able to buy low noise LED and low noise power supplies and see their noise rating.

Tau.Neutrino said:

I have found some LEDs are noisy around HIFI gear

Various LED light bulbs and even smaller LEDs on portable Hard Drives

I can pick them up on FM radio, also various switch mode power supplies can wipe out the radio.

I was wondering if there are any standards for computers, wifi modems, switch mode power supplies and LEDs for producing noise

Maybe give all products a noise rating like the 5 star energy rating system.

Create a 5 star rated noise standard and apply it to all electronic devices.

I’d like to be able to buy low noise LED and low noise power supplies and see their noise rating.

Have a look here. http://www.premierltg.com/what-makes-an-led-bulb-flicker-how-to-solve-led-flicker/

If the LED is fed a constant direct current then that may fix it. Perhaps?

“How to solve LED flickering issues?”

“LED flickering can be tied back to the driver component within the lamp. The essential purpose of the LED driver design is to rely on a simple circuit to control output current, but without altering the frequency, the LED becomes likely to show visible flicker. However, this can be fixed by using constant current drivers, which remove the peaks of the sine wave.”

Yes there are standards that products are required to conform to so that they can be sold in Australia. See:

http://www.techintl.com/australia.cfm

If you think that most of the chineseium products that land on these shores actually comply then I may have a bridge going cheap.

mollwollfumble said:

Tau.Neutrino said:

I have found some LEDs are noisy around HIFI gear

Various LED light bulbs and even smaller LEDs on portable Hard Drives

I can pick them up on FM radio, also various switch mode power supplies can wipe out the radio.

I was wondering if there are any standards for computers, wifi modems, switch mode power supplies and LEDs for producing noise

Maybe give all products a noise rating like the 5 star energy rating system.

Create a 5 star rated noise standard and apply it to all electronic devices.

I’d like to be able to buy low noise LED and low noise power supplies and see their noise rating.

Have a look here. http://www.premierltg.com/what-makes-an-led-bulb-flicker-how-to-solve-led-flicker/

If the LED is fed a constant direct current then that may fix it. Perhaps?

“How to solve LED flickering issues?”

“LED flickering can be tied back to the driver component within the lamp. The essential purpose of the LED driver design is to rely on a simple circuit to control output current, but without altering the frequency, the LED becomes likely to show visible flicker. However, this can be fixed by using constant current drivers, which remove the peaks of the sine wave.”

that wont help my problem

one LED is in a portable Hard Drive, its the read write indicator

the other LED is a 240 volt 8 watt LED for a desk lamp

I know various noisy switch mode power supplies can be replaced with better ones that produce less noise, I have some noisy headphone amplifier power supplies that came with the amplifier that also wipe out the FM radio.

sibeen said:

Yes there are standards that products are required to conform to so that they can be sold in Australia. See:

http://www.techintl.com/australia.cfm

If you think that most of the chineseium products that land on these shores actually comply then I may have a bridge going cheap.

That part of the industry needs a clean up.

Noisy electronics are a problem.

No one is doing much about it.

I have a noisy dc motor that my turntable cartridge picks up

Would a piece of aluminum foil under the record mat stop the stylus from picking up the hum?

Or is there another way to stop stylus picking up the DC motor hum?

sibeen said:

Yes there are standards that products are required to conform to so that they can be sold in Australia. See:

http://www.techintl.com/australia.cfm

If you think that most of the chineseium products that land on these shores actually comply then I may have a bridge going cheap.

Could the c tick be extended to a 5 star noise rating system?

>I was wondering if there are any standards for computers

certainly are.

fairly much anything with fast risetime pulses generates radio noise, and anything that switches fast does that, and fast switching times are often good for a few reasons, like during transitions a semiconductor is neither off or on, and consequently quite a bit of heat is lost there, across the junction, sort of IxV= W, to simplify. Switch it fast at a continuous rate and you have an oscillator, which will generate EMR on a/or particular frequency/ies, + sidebands, harmonics, spurious whatever.

my old computer, you could change it to spread spectrum, clocking of the bus I guess, so for countries where noise EMR requirements were tighter, well, it’d pass the test.

Tau.Neutrino said:

sibeen said:

Yes there are standards that products are required to conform to so that they can be sold in Australia. See:

http://www.techintl.com/australia.cfm

If you think that most of the chineseium products that land on these shores actually comply then I may have a bridge going cheap.

That part of the industry needs a clean up.

Noisy electronics are a problem.

No one is doing much about it.

I wouldn’t say that. Noises from computers and other electronic devices are very much less than they were 20 years ago.

I’m wondering if there are special low noise computers for sale now. It wouldn’t surprise me.

Checks web – golly there are a huge number of useless quack shielding devices out there. Can’t see anything better than a Faraday cage yet.

mollwollfumble said:

Tau.Neutrino said:

sibeen said:

Yes there are standards that products are required to conform to so that they can be sold in Australia. See:

http://www.techintl.com/australia.cfm

If you think that most of the chineseium products that land on these shores actually comply then I may have a bridge going cheap.

That part of the industry needs a clean up.

Noisy electronics are a problem.

No one is doing much about it.

I wouldn’t say that. Noises from computers and other electronic devices are very much less than they were 20 years ago.

I’m wondering if there are special low noise computers for sale now. It wouldn’t surprise me.

Wouldn’t say they are special but you can get some low powered computers that don’t make a sound, mainly because the have no active cooling i.e. a fan.

mollwollfumble said:

Tau.Neutrino said:

sibeen said:

Yes there are standards that products are required to conform to so that they can be sold in Australia. See:

http://www.techintl.com/australia.cfm

If you think that most of the chineseium products that land on these shores actually comply then I may have a bridge going cheap.

That part of the industry needs a clean up.

Noisy electronics are a problem.

No one is doing much about it.

I wouldn’t say that. Noises from computers and other electronic devices are very much less than they were 20 years ago.

I’m wondering if there are special low noise computers for sale now. It wouldn’t surprise me.

Checks web – golly there are a huge number of useless quack shielding devices out there. Can’t see anything better than a Faraday cage yet.

Low noise computers would be good to research.

Tau.Neutrino said:

mollwollfumble said:

Tau.Neutrino said:

That part of the industry needs a clean up.

Noisy electronics are a problem.

No one is doing much about it.

I wouldn’t say that. Noises from computers and other electronic devices are very much less than they were 20 years ago.

I’m wondering if there are special low noise computers for sale now. It wouldn’t surprise me.

Checks web – golly there are a huge number of useless quack shielding devices out there. Can’t see anything better than a Faraday cage yet.

Low noise computers would be good to research.

Agree.

mollwollfumble said:

Tau.Neutrino said:

mollwollfumble said:

I wouldn’t say that. Noises from computers and other electronic devices are very much less than they were 20 years ago.

I’m wondering if there are special low noise computers for sale now. It wouldn’t surprise me.

Checks web – golly there are a huge number of useless quack shielding devices out there. Can’t see anything better than a Faraday cage yet.

Low noise computers would be good to research.

Agree.

Cooling fans don’t have to be as big and noisy these days. Electrc motors are smaller smoother and quieter now.

roughbarked said:

mollwollfumble said:

Tau.Neutrino said:

Low noise computers would be good to research.

Agree.

Cooling fans don’t have to be as big and noisy these days. Electric motors are smaller smoother and quieter now.

Its more EMF noise than audible fan noise, audible fan noise is a problem as well, yes, one can buy reasonably quiet cpu fans now.

I know fan less cpu designs are available, but the cpu itself can generate emf noise, ideally this should be shielded, Ive discovered various monitors generate EMF noise as well, if not the monitor itself, then its the noisy switch mode power supply that comes with it.

then there’s the power supply of the computer itself

computer power supplies use a rating system of 80 plus

https://en.wikipedia.org/wiki/80_Plus

80 Plus (trademarked 80 PLUS) is a voluntary certification program intended to promote efficient energy use in computer power supply units (PSUs). Launched in 2004 by Ecos Consulting, it certifies products that have more than 80% energy efficiency at 20%, 50% and 100% of rated load, and a power factor of 0.9 or greater at 100% load. Such PSUs waste 20% or less electric energy as heat at the specified load levels, reducing electricity use and bills compared to less efficient PSUs.

80 plus
80 plus Bronze
80 plus Silver
80 plus Gold
80 plus Platinum
80 plus Titanium

How does it address noise levels ?

Tau.Neutrino said:

roughbarked said:

mollwollfumble said:

Agree.

Cooling fans don’t have to be as big and noisy these days. Electric motors are smaller smoother and quieter now.

Its more EMF noise than audible fan noise, audible fan noise is a problem as well, yes, one can buy reasonably quiet cpu fans now.

I know fan less cpu designs are available, but the cpu itself can generate emf noise, ideally this should be shielded, Ive discovered various monitors generate EMF noise as well, if not the monitor itself, then its the noisy switch mode power supply that comes with it.

then there’s the power supply of the computer itself

computer power supplies use a rating system of 80 plus

https://en.wikipedia.org/wiki/80_Plus

80 Plus (trademarked 80 PLUS) is a voluntary certification program intended to promote efficient energy use in computer power supply units (PSUs). Launched in 2004 by Ecos Consulting, it certifies products that have more than 80% energy efficiency at 20%, 50% and 100% of rated load, and a power factor of 0.9 or greater at 100% load. Such PSUs waste 20% or less electric energy as heat at the specified load levels, reducing electricity use and bills compared to less efficient PSUs.

80 plus
80 plus Bronze
80 plus Silver
80 plus Gold
80 plus Platinum
80 plus Titanium

How does it address noise levels ?

Generally supplies that have high efficiency will also have a reasonably low noise, as many of the techniques used to gain efficiency, zero volt switching and the like, also remove some of the noise producing components. With modern semiconductors and control silicon you’d actually be hard pressed to build a supply that has lower than 80% efficiency when above 25% load; although many really cheap chineseium supplies actually manage it.