You need to measure in the right direction, unless you have a three-axis detector that can measure in any direction, or else you will not get the right reading.
【在 t***k 的大作中提到】 : You need to measure in the right direction, unless you have a three-axis : detector that can measure in any direction, or else you will not get the : right reading.
不要图方便,还是买这个吧。毕竟是3轴的,而且可以测0.1 MHz – 2500 MHz。 注意:这个不同于AMAZON上卖的那个! Trifield® BroadBand 100XE Meter Manufactured in the USA by AlphaLab, Inc. The BroadBand Meter is a version of the Trifield ®Meter which has a modified radio/microwave section. (The magnetic and electric sections are identical to the Trifield Meter). The BroadBand Meter is preferred for measuring the field near transmitter antennas to determine whether enough output power is produced to attain a certain signal strength. The BroadBand Meter RF frequency range is 0.1 MHz – 2500 MHz, so it detects an additional frequency band (0.1 MHz – 50 MHz) not covered by the standard Trifield Meter. The BroadBand Meter reads in different units (kV/m or kilovolts per meter), which is the unit usually preferred by transmitter engineers. 这是AMAZON上卖的那个,要测变压器附近的还要BroadBand 100XE Meter Trifield ® Meter Model 100XE Manufactured in the USA by AlphaLab, Inc. ---------------------------------------------------------------------------- ---- Trifield ® Meter measures all three types of electromagnetic field: AC magnetic field, AC electric field, and radio (including microwaves). The magnetic and electric detectors are 3-axis, making the meter easier to use than comparable 1-axis meter (en français). *The Radio/Microwave section of this meter reads most modern radio sources ( 50 MHz - 3 GHz). For lower radio frequencies and/or stronger radio sources ( such as measuring the field near a transmitter), see the Trifield® BroadBand 100XE Meter.
【在 v****g 的大作中提到】 : 不要图方便,还是买这个吧。毕竟是3轴的,而且可以测0.1 MHz – 2500 MHz。 : 注意:这个不同于AMAZON上卖的那个! : Trifield® BroadBand 100XE Meter : Manufactured in the USA by AlphaLab, Inc. : The BroadBand Meter is a version of the Trifield ®Meter which has a : modified radio/microwave section. (The magnetic and electric sections are : identical to the Trifield Meter). The BroadBand Meter is preferred for : measuring the field near transmitter antennas to determine whether enough : output power is produced to attain a certain signal strength. The BroadBand : Meter RF frequency range is 0.1 MHz – 2500 MHz, so it detects an additional
the Earth's magnetic field can be 0.25–0.65 Gausses
s*n
58 楼
The EMF field and its link to human health, especially Child Leukemia has been a very controversial one. So far, there has only been some weak link based on some epidemiology studies. There is no biological or laboratory mechanism. Even 1000 Gauss magnetic field at 60 Hz does not cause cancer on mammal, so I think it's most likely linked to other factors, such as income. People near high voltage wires are usually in the low income class. It could be changing now, but at least it used to be the case when the studies were first published in the early 1980's.
k*g
59 楼
0.1 MHz – 50 MHz 是用来测什么的?
【在 v****g 的大作中提到】 : 关键看你测量的频率范围了。
k*n
60 楼
We have abandoned two properties so far because of its EMF readings. The concern is not only health related but also for future sale. So far the public opinion on this is still not defined. But if in the future everyone agrees that high EMF is not good, then you won't be able to sell your house. Sign, there are some very good properties out there. But if they are at the boundary of the subdivision with couple of electric poles and transformers in the back, the EMF reading is pretty high.
n*a
61 楼
mark
a*0
62 楼
我测了convection oven 的上面digital operated part, and found the EMF number pretty high, although I did not bake or preheat the oven. I tested in front of my microwave oven. even if it's not operating, the EMF number is also high right in front of the microwave oven when it is plugged to the outlet.
s*n
63 楼
Google search John E Moulder about power line EMF (which is 60 Hz frequency) . Note the cell phone tower is different from power line, because it's high frequency, 2.4GHz. Radio Frequency is possible to cause cancer, but ultra-low EMF like that ones generated by power lines are not possible to cause cancer.
f*i
64 楼
请问哪里能买到2.4GHz的cell phone
frequency)
【在 s********n 的大作中提到】 : Google search John E Moulder about power line EMF (which is 60 Hz frequency) : . : Note the cell phone tower is different from power line, because it's high : frequency, 2.4GHz. : Radio Frequency is possible to cause cancer, but ultra-low EMF like that : ones generated by power lines are not possible to cause cancer.