Please HELP. GHz vs MHz signals.

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I have an important question that I need help with. Because I'm not too versed in frequency bands, I wanted to post something here. If you have any official documentation, all the better. The question is this... Can a Phantom 4, operating at 2.4 Ghz cause interference to a communications tower, operating at 100-250 Mhz? The tower was 2.3 km away and 60 meters higher than the drone was flying. Do these frequency bands easily overlap and would it be likely for the drone to cause interference?

From my understanding, the GHz bands are not more powerful than the MHz ones, but rather are just in a different spectrum, yes?

Thank you in advance.
 

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From my understanding, the GHz bands are not more powerful than the MHz ones, but rather are just in a different spectrum, yes?
GHz and MHz are an indication of the frequency - not the strength of signal.
I have an important question that I need help with. Because I'm not too versed in frequency bands, I wanted to post something here. If you have any official documentation, all the better. The question is this... Can a Phantom 4, operating at 2.4 Ghz cause interference to a communications tower, operating at 100-250 Mhz? The tower was 2.3 km away and 60 meters higher than the drone was flying. Do these frequency bands easily overlap and would it be likely for the drone to cause interference?
Your Phantom has no effect on anything 2 km away, let alone a communications tower using 100-250 Mhz.
This shows how far apart the frequencies in question are:
 
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Thank you for the info. Would you happen to have any documents to support this? It would be great if I could print off something to present.
 
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Thanks... lol. That's how I feel right now but I need to present something that they can easily understand and grasp.
 
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There has to be some type of article about how the higher bands are not likely to interfere with the lower ones. I've been going through the internet but having a hard time. And yes, I'm being charged with causing interference in a remote country that's not familiar with drones. That's why it needs to be simple.
 
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There are lots of RF signals in the air, but the receiver is tuned to only pick up a certain frequency. If it is interfering with their antenna I'd say something is wrong with their receiver. But I'm definitely no expert.


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Meta4

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Thank you for the info. Would you happen to have any documents to support this? It would be great if I could print off something to present.
Is someone seriously suggesting your Phantom caused a problem?
Your Phantom wouldn't cause interference 20 metres away, let alone 2km away - the idea is laughable.

Do you have any idea how many radio sources there would be within 2 km of the tower?
If Phantoms caused problems at 2km, no-one would ever hear their phone calls because of all the other interference there would be.
But radio doesn't work like that.
That's why the radio spectrum is carefully managed with different uses being allocated their own frequencies.
 
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Yes, I'm outside the USA on a trip and now have this issue to deal with. I understand what you're saying. It's a pretty big headache but I need documentation showing that the 2.4 GHz signal from the P4 is not likely at all to interfere in the 100 MHz frequency spectrum. Something really clear and definitive.
 
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Email DJI , I would be willing to bet they have heard of this before & have an answer for it .
 

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Since
Yes, I'm outside the USA on a trip and now have this issue to deal with. I understand what you're saying. It's a pretty big headache but I need documentation showing that the 2.4 GHz signal from the P4 is not likely at all to interfere in the 100 MHz frequency spectrum. Something really clear and definitive.
It sounds like you are dealing with an idiot and it's unlikely anything would make any difference to them.
If they can't understand that a tiny transmitter putting out less than 0.5 watts (that's the transmitting power) on a frequency miles from the frequency of the tower equipment and at a distance of 2km has zero effect, you won't convince them with documentation.
If the communication system was that sensitive, it would be swamped by everything else out there and wouldn't work at all.

Here's the specs for the radio control.

Remote Controller
Operating Frequency 2.400 - 2.483 GHz and 5.725 - 5.825 GHz
Max Transmission Distance 2.400 - 2.483 GHz (Unobstructed, free of interference)
FCC: 4.3 mi (7 km)
CE: 2.2 mi (3.5 km)
SRRC: 2.5 mi (4 km)
5.725 - 5.825 GHz (Unobstructed, free of interference)
FCC: 4.3 mi (7 km)
CE: 1.2 mi (2 km)
SRRC: 3.1 mi (5 km)
Operating Temperature Range 32° to 104°F (0° to 40°C)
Battery 6000 mAh LiPo 2S
Transmitter Power (EIRP) 2.400 - 2.483 GHz
FCC: 26 dBm
CE: 17 dBm
SRRC: 20 dBm
5.725 - 5.825 GHz
FCC: 28 dBm
CE: 14 dBm
SRRC: 20 dBm
 
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What if I change tactics?

Because I'm in Africa, does my P4 automatically switch to CE mode thus lowering the effective range of the drone? If the drones signal in CE mode is limited to 2 km then me being 2.4 km's away proves I couldn't have interfered with its signal... ??

Thoughts?
 
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Are they holding you captive till you come up with documentation that proves otherwise? I guess what I'm saying is, is giving them the finger and telling them to f*** off not an option?


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Yes, that is exactly my situation. I need input on the CE mode because that could exonerate me.
 
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Contact the American Embassy?

Field test/duplicate problem?

I googled but just found other forums talking about frequencies.


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Meta4

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What if I change tactics?

Because I'm in Africa, does my P4 automatically switch to CE mode thus lowering the effective range of the drone? If the drones signal in CE mode is limited to 2 km then me being 2.4 km's away proves I couldn't have interfered with its signal... ??

Thoughts?
That's not how radio works. It doesn't go some fixed distance.
If the people you are dealing with have such a lack of understanding of how radio works, I wouldn't count on being able to satisfy them.
Tell them your transmitter is tiny .. less than half a watt and the frequency is miles away from the communications system frequency

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It could help to know a little more information about this "communications tower".
Is it commercial, military or other?
Is it a transceiving (transmit and receive) or just a transmitting antenna?

This could be a case where a person is just looking at a spectrum frequency scope and see's a spike at your operating frequency and assumes it's going to interfere. While I don't know the allowable output power levels for ham radio operators in the country you are speaking about, there could easily be a person allowed to transmit up to 5.0 watts (as opposed to 0.5) with a hand held radio that is transmitting on a frequency a LOT closer to their stated frequency.

Random thought, is communications interference the actual problem or do they just not want drone flying? Your own investigation in communications and drone flying regulations in this country would help here.

Just to note, I certainly don't know the laws of this country. You may not have options like we do in the USA. Please be careful.
 
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100 MHz = 0.1 GHz. Wireless routers also work in the 2.4 and 5 GHz band. That means anyone with a wireless router could cause interference if this was the case. My wireless phone also operates around 2.4 GHz yet my Phantom doesn't interfere with it or my WiFi. All these devices work on narrow channels within that band.

If it were possible for a 2.4 GHz signal to cause interference within the 100-250 MHz band then every wireless router and wireless phone in the area would be suspect. I don't know what it is like in your area, but around here I detect more th an 10 wireless networks just around my house.
 
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How could any rational human being think that something emitting a signal with a wavelength measured in centimeters interferes with something emitting a signal with a wavelength measured in meters? This concept is taught in like 7th grade, at least in the US.... maybe refer them to their local middle school's physics teacher?
 

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