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Plasma TV radiation ?

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Nofear4xjs

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Hello, anyone know what it is that makes my bettery operated am radio act like a ranging Baboon on a bad dose of crack?

Explaination : I tune in my am radio between station frequencies and at the lowest frequency I can then turn on my plasma 42 inch TV and it starts screammmming untill I get about 10 feet away. WTF is this just static electricity or something else?
 
A plasma TV makes radio frequency noise.
Any digital circuit makes radio frequency noise.
Switching power supplies like the one in you TV makes radio frequency noise.

With your radio tuned to 'no station' it will find any noise on that frequency.
 
For a product to be sold to consumers they must pass strict tests. (RF radiation) There is a big difference between one product and another. There are different levels depending if the product is for a hospital or a home use.
 
An AM radio picks up all kinds of interference. An FM radio rejects most interference.
 
Thanks for the replies, but you have not addressed the question. It`s radio frequency noise or radio frequency interference or Electromagnetic polution...

No kidding it`s interference come on seriously... Can anyone give a more detailed explaination of what is causing the interference, what exactly is causing it?

I have an RF meter but it only reads down to 50 mhz and up to 3.5 Ghz so no luck with that the readings did not change when the TV was power on. I have an AC milligauss meter but when I back away from the TV the reading goes way down and is consistant with the reads of my whole place at about 1 foot away.

I ground my multimeter and touch the other probe and get no change in voltage standing or even touching the TV, when I touch my lamp pole I get about 6 to 10 volt reading or when I touch an extention chored same thing I get an instant reading of 6 to 8 volts.


Thanks again for your replies, I`m just looking for more thought through or knowledgeable answers.

Cheers, or eat some healthy food if thats your thing :]

Tenmars TM-195 RF meter 50MHZ to 3.5GHZ
Alpha Lab UHS2 milligauss meter for AC magnetic feilds 13HZ-75KHZ
 
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The plasma TV produces amplitude changes with harmonics at radio frequencies. Its wiring is the transmitting antenna.
An AM radio picks up amplitude changes because AM is Amplitude Modulation. An AM radio picks up 540kHz to 1.6MHz.

Your multimeter might be designed to be sensitive only to the 50Hz or 60Hz of AC electricity then it will not pickup radio frequencies.
 
Ok thanks for the detailed reply.
So if I understand correctly that am radio would not be screaming with interfernece if it was below or above the 540kHz to 1.6MHz range ?

So My gauss meter is not picking up anything so it must be above 75,000 HZ range and the RF meter only reads above 50MHZ so the interference must be between 75,000 hz & 50,000,000 hz, correct?

EDIT; Ok I don`t know how this slipped by me but I`m sure my TV is 600hz the power source is still 60hz of course...

Thanks again for your time, I`m doing online searches but when it comes to fusion and plasma I`m lost...
 
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With the TV on and playing the new Star trek blueray the reading I got against the screen fluctuates from abour 20mg up to 70+ milligauss the darker the screen the lower the mg, from about 1 foot away and it reads 0.20 to 0.18 so no harmfull magnetic interference when sitting far away from the screen.

Not so sure about the RF & electric radiation but it`s enough to make my plants grow scrawny and tall as appose to the normal short and stalky way they grow normally.
 
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As others have mentioned, the AM radio is responding to electromagnetic radiation from the TV. Well, in fact, it is mainly responding to magnetic radiation as a result of the antenna in the AM radio being a loop type ferrite bar antenna. The AM radio is a tuned receiver, able to receive only a little 10KHz slice of spectrum at any one time, at whatever frequency it is tuned to. You will find that the AM radio will probably pick up noise when you bring it close to your PC, your tablet computer, your cellphone, your cordless phone, compact flourescent and LED lightbulbs, your TV, your stereo, your wireless router, your microwave oven, your coffee maker and pretty much anything else electronic that is switched on at the time. This is because all of these devices nowadays use digital electronics of some sort to do their thing and digital electronics tend to generate radio noise.


The reason that they are doing this is fundamental to the way they operate. Digital electronics relies on digital logic. In digital logic, the electrical signals are binary, that is they are either at one voltage or another. Logic circuits and computers compute things sequentially, and as a result, the logic signals inside them are constantly changing at high speed between one voltage and another. To work correctly, they must go from the one voltage to the other as quickly as possible and herein lies the core reason why RF is generated. When you force a voltage in a circuit to change very quickly, you are also causing a rapid change in current flow (ohm's law must hold), so in fact you are causing a rapid change in power. It is a fact of physics that such a rapid change is done by involving a large range of spectrum. What this means to the non-physics person is that a broad spectrum of harmonics are generated, in which there is significant power. All electronic logic must generate harmonic energy in order to function, and it is the hope of the designer of each product that he can keep that energy inside his circuits, and not let it get out. But this hope does not often translate to result. Because of sloppy design, and/or because it is so blasted difficult to keep the radio frequency power inside one's circuit, the harmonic power finds its way out via radiation. You will find that of the many different kinds of receivers you might have handy, the AM radio will be hit the hardest by this. This is for a couple of reasons. One is that it is receiving relatively low frequencies, like 500KHz for example. It is a fact of physics that the harmonic energy generated in electronic devices tends to be strongest at the lowest frequencies and tends to die down as the frequency goes up, although this is not a rule you can apply in all cases. AM radio is listening to a very low frequency indeed, so it gets the worst of it. The other reason is that it is AM radio, making it sensitive to changes in RF amplitude, and it is RF amplitude that is jumping up and down a lot in the radiation from digital logic, so the AM radio is designed to hear the worst of digital emissions. This is unlike, say, your FM radio which is typically not very sensitive to AM, and unlike your cellphone or your wireless router, or for that matter, your TV remote control which are operating at much higher frequencies.
 
Thank you for the detailed reply you have explained alot I did not understand.
The below stated is for anyone who might stumble accross this thread and get interested in EMF polution.

Looks like I have some more research to do on harmonics, I already know that harmonics can be dangerous as they can add to the harmonic radiation already present in your house wiring due to the transformers inside appliances and electronic gadgets, when these transformers change the power source from AC to DC it causes harmonics and a very high magnetic field around it.

My digital alarm clock pulses from 337 to 367 milligauss with the meter on top of it and 2 milligauss at 10 inches away, anything above 1 milligauss is a small risk of serious heath affects, especially for children & anything above 5 mg is considered high risk of serious heath affects as stated by emwatch.com
RF harmonics also add to the power frequency harmonics it`s all very crazy the further you dig the crazier the world is. Look up dirty electricity is just nuts and stray voltage and cows WTF this is insane.
 
Thank you for the detailed reply you have explained alot I did not understand.
The below stated is for anyone who might stumble accross this thread and get interested in EMF polution.

Looks like I have some more research to do on harmonics, I already know that harmonics can be dangerous as they can add to the harmonic radiation already present in your house wiring due to the transformers inside appliances and electronic gadgets, when these transformers change the power source from AC to DC it causes harmonics and a very high magnetic field around it.

My digital alarm clock pulses from 337 to 367 milligauss with the meter on top of it and 2 milligauss at 10 inches away, anything above 1 milligauss is a small risk of serious heath affects, especially for children & anything above 5 mg is considered high risk of serious heath affects as stated by emwatch.com
RF harmonics also add to the power frequency harmonics it`s all very crazy the further you dig the crazier the world is. Look up dirty electricity is just nuts and stray voltage and cows WTF this is insane.

The only 'nuts' thing around here is you - your crazy theories have no place on any sensible forum :p
 
A technical explanation:
There are two kinds of interference you may be suffering from.
1. In band.
The Plasma TV is radiating signals that fall into the AM band. These are probably from the switching power supplies used for the screen. AM is very susceptible to noise from such devices. Even a small calculator can emit in band interference at sufficient levels to interfere. There is nothing you can do apart from moving it away from the TV as these signals are seen as possible radio signals within the AM band.

2. Out of band.
Problems caused by out of band signals are caused by the radio. An AM radio will generally be made of cheap components for the mass market and may contain little or no filtering on the radio's front end amplifiers. As a result out of band signals, if strong enough can overdrive the electronic amplifiers in the radio causing non-linear products and end up producing in band interference.

In the days of CB radio, it was known as "bleed over" where someone on an adjacent channel with a strong signal could produce a signal albeit outside your filter bandwidth, but of sufficient level to overcome the filter's performance (the interfering signal is above the stop band attentuation of your filter). Hence the demodulator would try and demodulate their signal as well as your own thus reducing the general sensitivity of your receiver...and you would hear their conversation too.

As already said, There are very strict guidelines put on manufacturers on the amount of unwanted radiation they can emit. However tied down this may be, a cheap AM radio will still get interference.
 
I was interested in translating your milligauss meter readings to values that I am more familiar with, mainly watts per square meter and I find that the conversion is not simple and requires a bit more effort than I was prepared to offer. However, I have a higher level concern here that bears discussion. You appear to be concerned about affects of electric and magnetic fields on your health. You need to understand that this is a highly politicized topic, and in such cases, the information that you will find on casual survey of the web will be a huge range of facts, misunderstandings, misinformation, propaganda, lies, truths, and wisdom. You must be very skeptical of every claim, no matter if the claim supports or refutes a position, no matter the apparent credentials of the one stating the claim. It is my understanding that the scientific community is still working on this topic, so even the best minds do not necessarily have all the facts. However, I would be more inclined to believe the results of good science more than anything else. Good science is also difficult to find these days as its seems that any layman with an opinion has access to the same voice as the genuine scientist, whether that be through the internet, television, magazines, or the street corner. It is difficult indeed, these days, to find the truth. Your view of this all may be crazy because, it is as if you are viewing a building worksite through a fence in which your entire view is through a half inch hole in the fence. And this worksite has thousands of labourers bumping in to each other and chattering loudly. Its no wonder it appears crazy.
 
This is an old topic, but it’s something I worked on not too long ago. I have a plasma TV and I am a ham operator with many receivers, mostly vintage tube type AM ones, but plasma radiation also interferes with the other modes such as SSB and CW.

What I found is most of the radiation is coming right from the plasma displays themselves more than it is coming from any connected cables. The radiation harmonics change as the picture changes. It’s mostly due to the plasma ionization process (discharge) and the interference changes (moves around in frequency) with the display rate (discharge rate).

There is not a whole lot you can do about it and if the TV is in close proximity to your antenna or receiver then you are screwed, even if it’s your neighbor a house or two away. If it’s still close enough you will hear it. It’s mainly coming from the plasma display itself though.
 
A plasma set, unlike a LCD, requires relatively high voltage to turn the pixels on and off (rather like a neon bulb) and this is occurring at the refresh rate of the TV. This generates significant wideband interference due to the harmonics from this high voltage switching.
 
A plasma set, unlike a LCD, requires relatively high voltage to turn the pixels on and off (rather like a neon bulb) and this is occurring at the refresh rate of the TV. This generates significant wideband interference due to the harmonics from this high voltage switching.
Yes, plasma TV supplies require higher voltages than LCD's, but it's the ionization process itself (the constant discharging) that's causing the EMF radiation and it the strongest within the MF and HF bands segments.

I think what alludes a lot of people is that Plasma TV’s work because an actual nuclear reaction is occurring. When they say plasma they mean plasma for real. It’s coming mainly from the displays themselves. Sure, the HV is in fact driving that reaction, but the reaction itself is the main source of the EMF. It is so strong that it does also get induced on the ground system and will appear as common mode on the cables, but what’s coming from the displays themselves is much strong than anything coming from the cables.

Hope that helps…
 
I moved from a suburban neighborhood to a rural setting about three years ago. During the five years I lived in the previous place, the ambient noise level on 40meters gradually went from S5 to S9+ to where I couldn't maintain a long standing radio schedule. I moved mostly to get away from the racket.

I attribute the increase in RFI to switching power supplies, plasma TV, CFLs, Electronic ballasts in florescent fixtures, LED lighting, etc. At my new digs, the noise level is S1 or less, and I intend to keep it that way (I shoot switchers with my rifle or shotgun, and I use real incandescent lamps). I can hear stuff on 40meters that I never even knew existed.
 
A plasma set, unlike a LCD, requires relatively high voltage to turn the pixels on and off (rather like a neon bulb) and this is occurring at the refresh rate of the TV.

No, it's at a considerably higher frequency - plasma displays can only be ON or OFF (it's a binary display) - in order to give variable brightness the display is fired multiple times per field, normally 256 times.

This is the main source of the RF emissions, but it also comes from the high power 'switch mode' X-SUS and Y-SUS boards, plus of course a much smaller amount from the SMPSU (although even this is a lot higher than an LCD set due to the greater power consumption.

But certainly Plasma TV's generate massive amounts of interference, I don't see how they ever got approval?.
 
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