Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

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Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
This post was updated on .
I want to know whether there is a way to measure electromagnetic radiation between 1khz and 30mhz with reasonable accuracy without spending a fortune.

AM radio doesn't give me quantities such as microwatt per square meter.

Ideally, I want the lower bound of measurable frequency range to be 1khz. If that's not possible at a reasonable price, I want it to be at least 200khz.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
This post was updated on .
the RF Explorer WSUB1G+ if you can get the proper antennas for it.
these may cost more than the meter itself.
copied from old post :

https://www.hamradio.co.uk/aerials-amateur-antennas-portable-antennas-wonder-portable-antennas/wonder-wand/wonder-wand-widebander-pd-2914.php
plus https://www.hamradio.co.uk/accessories-coax-connectors-and-adaptors/hamradio/cable-cab-so239-sma-65-pd-336.php
In the range from 50 KHz to 2 MHz you need a ferrite bead coil type antenna as well.
I am still looking out for cheap antennas that do the trick well enough for my purposes before getting also this new meter, which looks handy and useful within an important frequency range where most emf-detectors or -analysers do little or nothing.
More info : http://j3.rf-explorer.com/60-rfe/specifications/196-rf-explorer-wsub1g-plus

i found another antenna for it, must search for the model again.

this is the newest rf explorer, from 50 kHz upto 6GHz :
https://www.exp-tech.de/zubehoer/labor/messtechnik/9976/rf-explorer-6g-combo-plus-slim
it looks great for its price ( including european value-added-taxes here, you may get it cheaper ).
do not expect a fast sweep.
with a bunch of additional antennas, it could be useful.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
I'm a bit confused. Can you come back later when you can definitely recommend specific affordable devices?
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
no i can not recommend definitely any affordable meters.
emf-meters are all crap ( to different degrees ) , and the frequency-range between 100 kHz and 100/700 MHz has unfortunatedly been mostly ignored.
others on this forumhave played with several very cheap devices that may be of some use
.
the RF Explorer WSUB1G+ would work with additional antennas that cover the frequency range you want to explore.
for instance :
20 kHz - 300 MHz : https://www.hamradio.co.uk/accessories-by-manufacturer-bonito-accessories/bonito/bonito-boni-whip-active-antenna-20khz-300mhz-pd-7134.php
but you'll need a patch cable from sma male male to bnc male for it.
correction previous post : the patch cable mentioned for the wonderland antenna won't fit to neither of these antennas.
those that are handy ans a bit technical could perhaps produce at home a ferrite bead coil type antenna for the range from 50 KHz to 2 MHz.
antennas should not deliver more than 16 volt dc to the RF-explorer.
the meter could be damaged when exposed to very strong fields ( like within one or two feet of a wifi-modem ), even when the meter is switched off.

the RF Explorer WSUB1G+ gives a spectrum analysis.
it produces emfs on its own, so not recommendable for everyone.
with "slow sweep" i actually meant something else : slow response.

the ME 3851A  from Gigahertz Solutions : 5Hz to 100 kHz ( actually a bit higher upto 500 kHz but than less sensitive ) rather reliable and solid, with ticking warning sound on it is less accurate.

the Esmog Spion :  1Hz - 80kHz + 80 kHz to 3 GHz
certainly some semblance of accuracy .
different sounds help to distinguish between different signals but this does not replace is a spectrum analysis of course.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
This post was updated on .
* On Esmog Spion manual PDF, Esmog Spion was only tested between 3MHz and 3GHz.

* I was considering Safe and Sound Classic. I read test result. It doesn't seem accurate below 800MHz. What is effective measurable range of frequencies of Safe and Sound Classic?

https://www.slt.co/Downloads/Shared/Final-safe_and_Sound_RF_Testing_with_Calibration_Certificates.pdf
https://www.slt.co/Products/RFDetectors/SafeandSoundRFDetector.aspx

I was thinking about having Esmog Spion and Safe and Sound Classic complement each other.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
these tests apply one clean signal of a single frequency at at time.
under real world circumstances the performance is quite another story.
from a distance this "safe and sound" meter looks like expensive garbage to me.
most rf-meters are far from accurate below 700 MHz, whatever may be claimed.
above 3 GHz it is usually not much better.
the rf-explorer gives some value for money including reasonable spectrum analysis.
the sound of the esmog spion helps finding many sources of emfs.
e.g. a central heating boiler may produce a strange peep on the esmog spion.
no other meter that i know off will detect this LF field.
it is an amazing instrument but a bit fragile built.
a new model will be launched in august (!).
https://www.endotronic-gmbh.de/messger%C3%A4te/5g-esmog-spion/
pretty exciting after decennia of beating other new meters with its old model.

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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
This post was updated on .
The latest revision of Safe and Sound Classic and Safe and Sound Pro 2 claims to measure electromagnetic radiation between 400MHz and 7.2GHz with +/- 6dB accuracy.

-6dB means 25% of actual power. 6db means 4 times actual power.

So, it may measure 600MHz and above with some semblance of accuracy if their claim is correct.

Are you sure 5g esmog spion actually measures electromagnetic radiation between 50Hz and 8GHz?
I read that a meter usually has to measure 3 wavelengths away from the source to get accurate measurements.
I want to measure 250khz and 500khz from wacom cintiq. 3 wavelengths for 250khz are about 1200 meters from the source. I'm worried about my arm and my face when I use wacom cintiq.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
the 5g esmog spion is not yet available, but soon we could try it out.
the old esmog spion picks up 50 Hz very well and frequencies in the kHz range certainly too.
no meter will detect all and everything within their specifications, a lot of signals will go unnoticed.
when confronted with a mixture of emfs ( pretty normal outside of testing labs ), the performance gets even much worse.
i think that the esmog spion is not that accurate but misses less important signals than average.
the clear sound output is valuable as it helps to distinguish between different signals.
i've never heard of that 3 wavelengths rule, but at higher frequencies it certainly seem to apply to some extent.
below 1 MHz i guess there is no need to worry about this, the question is also how to define the word "accurate".

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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
I want to know whether 5g esmog spion can actually measure electromagnetic radiation between 1khz and 30mhz(dirty electricity) without gaps.

I'm also interested in frequencies around 250khz and 500khz(wacom cintiq).

Can you submit your test result here after using 5g esmog spion? If you know someone near you who has wacom cintiq, can you also test 5g esmog spion with wacom cintiq?
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
almost certainly no affordable meter is anywhere near reliable.
so you do not need to wait for amateur testresults.
apart from being inaccurate, emf-meters do not show health-effects on an individual level.
to quickly test monitors i often use this : https://www.heliognosis.com/emm.html
way too expensive for what it is, ignore the specifications totally, but it seems responsive in the kHz range.


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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
Are you saying that even Safe and Sound Pro 2 doesn't indicate health effects in the frequency range it claims to measure with +/-6dB accuracy?

Or, are you saying that there is no affordable meter that measures kilohertz range with any accuracy?
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
This post was updated on .
both, by far no such accuracy under real world circumstances in any claimed range.
skip the word "even" related to those Safe & Sound toys.
not even :
https://aaronia.com/spectrum-analyzers/spectran-v4-handheld-sweep-analyzer/
plus
https://aaronia-shop.com/products/portable-isotropic-antenna-pro-version
plus
https://aaronia.com/spectrum-analyzers/spectran-nf-handheld-niederfrequenz
i had the latter years ago and returned it because of some clearly wrong readings

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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
This post was updated on .
What do you recommend, then for measuring all kinds of EMF?

I'm considering

* Safe and Sound Classic for electromagnetic radiation between 400MHz and 7.2Ghz
* Gigahertz Solutions ME3030B for electric field and magnetic field

I have

* TriField TF2 which is good for 3-axis magnetic field measurement. This doesn't measure pulsed electromagnetic radiation.
* TriField EM100 which measures dirty electricity on hot wire between 10khz and 10mhz
* Sony ICF-P26 portable AM radio for listening to electromagnetic radiation between 530khz and 1600khz.

I really don't have a tool that measures electromagnetic radiation between 1khz and 30mhz.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
In reply to this post by earthworm
Ron Frazier suggested that I could measure magnetic field component of electromagnetic radiation in a close distance.
Electric field measurement is unreliable because electric field is blocked by obstacles, but magnetic field is not.

Spectran NF-5030 measures magnetic field between 1Hz and 30MHz.

I don't know whether magnetic field can be converted to dBm, V/m, uW/m^2, etc, ...
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
In reply to this post by earthworm
Have you had any luck with RF Explorer 6G Combo PLUS or RF Explorer WSUB1G PLUS?
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

kara
In reply to this post by earthworm
it's seems difficult to find a reliable meter. I have one for electric and magnetic readings, which seem alright, from Gigahertz (but I'm no expert), but for micro-, radio waves etc, I still have not been able to make up my mind. I did buy 3 years ago the original esmog spion, but honestly I did not understand how to handle/read it, so I returned it. At least concerning my Gigahertz meter, I understand the basics and how to use it.
So what kind of meter would be recommended? It does not need to be super accurate, but show the general picture, and be useful, and relatively easy to read/handle. Thanks for any advice/recommendation. (Btw, I live in Europe, so maybe a brand available here would be easier).
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
In reply to this post by black-sun
just compare the antennas of the Gigahertz and Aaronia RF-meters with a Safe&Sound.
forget about specifications, that's just sales talk and deception.
i appreciate you take measurements seriously.
in the past we had Charles here at the forum, that could have given you better advice.
what i can say is that it ain't easy, even more so in the lower MHz range.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
In reply to this post by black-sun
usually above about 1 MHz one does not distinguish between electrical and magnetic fields.
wether only for practical or also for theoretical reasons, i do not know, but that does not matter for us.
i do not think you can convert milliGauss or nanoTesla into dBm, V/m or uW/m^2.
even if you could, you would be comparing apples with oranges to a too large degree.
every frequency and type of wave form has a different impact.
in addition combinations of fields make for a different outcome.
finally health effects are highly personal(  and even changing with time ), not everyone is affected in the same manner.
therefore, although not reliable either, one's own sensitivity is probably usually the best meter.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

black-sun
In reply to this post by earthworm
It's clear that TriField deceived me with TriField TF2's specifications because TF2 cannot measure 5Ghz WiFi.

I cannot know whether 9CI deceived me with Safe and Sound Classic's specifications unless I have a lab equipment myself or watch a measurement video made by a third party lab.
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Re: Is there any way to measure electromagnetic radiation between 1khz and 30mhz?

earthworm
This post was updated on .
Right.
I like the TF2 though nevertheless, but its RF-detection sucks.
A Cornet is definitely much better at frequencies between 700 MHz and 3 GHz ( but in the Hz and kHz range it is the other way around ).
All meters without decent antennas are to be expected to be very unreliable.
A good picture of it you'll get here ( posted again given this context ) :
https://www.emfanalysis.com/wp-content/uploads/2016/01/German-Test-Report-RF-Meters.pdf
The Safe&Sound is too expensive for a crap-meter.
The Gigahertz HF meters will be much more precise and the Cornets will probably give better value for buck than the Safe&Sound.
For 5 GHz wifi and 5 GHz DECT the new RF Explorer 6G COMBO+ ( slim version ) seems a wiser choice.
It has an antenna for both wifi ranges and antennas for 144-900 MHz, additional antennas can be sought and bought.
Just with its telescopic antenna, although designed to measure below 430 MHz, it will probably yield much better results upto 6 GHz than the Safe&Sound, and i expect it to be far superior in the 5 GHz range with its wifi antenna.
But readings will not be that instant, it is an analyser and sweeps over a preferred range which takes more time but provides more data and likely misses less ( but still some and possibly quite some ) signals if you're a bit patient ( and there will likely be some false or "ghost" readings, as in all meters ).
Also it is less easy to use than most EMF-meters.
https://j3.rf-explorer.com/menu-models
The near field probes may be useful to test above 1 MHz ( to 7 GHz ) at very close distances :
https://statics3.seeedstudio.com/assets/file/bazaar/product/RF_Explorer_NF_Antenn_a_Kit_datasheet.pdf
It is noteworthy that following this info it seems that nearby an EMF source there is also above 1 MHz a distinction to be made between electrical and magnetic fields.




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