diy Turning an old Satellite dish into a cellphone signal booster

[bob345]

The dish you have is most likely designed for ku band radio, which a WAY out of range of 4g or even standard phone service. it would be like trying to pick up shortwave radio with a wifi antenna, it just wont happen. RF hardware is very often very specialized for only a certain frequency band so there is also a prey high chance that the dish has a built in bandpass filter that only lets ku band radio through.

[knightslugger]

12 hours ago, bob345 said:

The dish you have is most likely designed for ku band radio, which a WAY out of range of 4g or even standard phone service. it would be like trying to pick up shortwave radio with a wifi antenna, it just wont happen. RF hardware is very often very specialized for only a certain frequency band so there is also a prey high chance that the dish has a built in bandpass filter that only lets ku band radio through.

have you ever tried it?

[bob345]

On 4/14/2018 at 10:46 AM, knightslugger said:

have you ever tried it?

No need, like I said, rf hardware is very specialized for it's intended band. A highly directional dish meant for 10-12 GHz ku band is not going to work with 4glte which is around 1900mhz. 

[knightslugger]

Just now, bob345 said:

No need, like I said, rf hardware is very specialized for it's intended band. A highly directional dish meant for 10-12 GHz ku band is not going to work with 4glte which is around 1900mhz. 

it's a parabolic reflector, not a radiator.

 

i would however like you to explain why a reflector used for 10GHz doesn't work for other frequencies. Because i know for a fact (and in practice) that it does...

[Scheer]

5 hours ago, knightslugger said:

it's a parabolic reflector, not a radiator.

 

i would however like you to explain why a reflector used for 10GHz doesn't work for other frequencies. Because i know for a fact (and in practice) that it does...

@bob345 Mentioned filter, so he is likely thinking OP is trying to use the feedhorn of the dish as well, and if that was the case he is correct in saying it will not work as they only allow the set frequencies through.

 

[knightslugger]

2 hours ago, Scheer said:

@bob345 Mentioned filter, so he is likely thinking OP is trying to use the feedhorn of the dish as well, and if that was the case he is correct in saying it will not work as they only allow the set frequencies through.

 

I think ...i just had a stroke...

 

The OP is talking about taking a DISH, a regular roof/wall mounted metal parabolic reflector, strapping his cellphone to the focus, and tapping that hot-spot button.

 

Honestly, i have no idea how you'd even get the feeder to come even remotely close to working. i mean unless you're talking about external boosters as we were a LONG time ago...

[bob345]

11 hours ago, knightslugger said:

it's a parabolic reflector, not a radiator.

 

i would however like you to explain why a reflector used for 10GHz doesn't work for other frequencies. Because i know for a fact (and in practice) that it does...

Because your gain will be pure garbage and you would be better off on just using a proper antenna by itself. beam width is something that you actually have to pay attention to. parabolic reflectors are not mirrors. We're talking up to a 26bd drop in gain on a 20 inch dish here because the reflector was NOT designed for these lower frequencies. You want more sensitivity at a lower frequency, you need a larger antenna. Same goes for parabolic reflectors. Sure, it might "work" as in you can pickup and transmit a signal, but you just threw your sensitivity out the window. Get your hands on a spectrum analyzer and see for yourself if it was really working so well for you.

[knightslugger]

11 hours ago, bob345 said:

We're talking up to a 26bd drop in gain on a 20 inch dish here because the reflector was NOT designed for these lower frequencies.

And how did you arrive at that number? What elements of a parabola make it ill suited for one frequency vs. another?

[bob345]

30 minutes ago, knightslugger said:

And how did you arrive at that number? What elements of a parabola make it ill suited for one frequency vs. another?

Take the size of a typical satellite TV dish and plug that into your typical beamwidth calculation formula. Wavelength vs size is what makes one more suitable for one job than the other. It's just basic antenna design. 

[knightslugger]

2 hours ago, bob345 said:

Take the size of a typical satellite TV dish and plug that into your typical beamwidth calculation formula. Wavelength vs size is what makes one more suitable for one job than the other. It's just basic antenna design. 

i'm confused. are you making an academic argument, or do you really believe that the wifi connection i have at my property using a nanostation M5 and a parabolic reflector that is over 5 miles long doesn't actually work?

[bob345]

7 hours ago, knightslugger said:

i'm confused. are you making an academic argument, or do you really believe that the wifi connection i have at my property using a nanostation M5 and a parabolic reflector that is over 5 miles long doesn't actually work?

Given the spec of the nanostation m5 and it being a 5ghz connection, I don't doubt that it works as Loss in gain will be much less at that frequency and you might even gain a few db over a standard 5ghz antenna, but that is a MUCH different application using a completely different kind of modulation. Like I said before, parabolic reflectors are NOT mirrors. There is allot of engineering and modeling that goes into designing rf electronics, it's not as simple as just putting an antenna in front of a dish.

[knightslugger]

16 minutes ago, bob345 said:

Given the spec of the nanostation m5 and it being a 5ghz connection, I don't doubt that it works as Loss in gain will be much less at that frequency and you might even gain a few db over a standard 5ghz antenna, but that is a MUCH different application using a completely different kind of modulation. Like I said before, parabolic reflectors are NOT mirrors. There is allot of engineering and modeling that goes into designing rf electronics, it's not as simple as just putting an antenna in front of a dish.

i can make a cw radio that can be heard almost around the globe from radioshack parts bins in an altoids tin and a clothesline. don't tell me there's a lot of engineering and modeling that goes into RF electronics...

[bob345]

13 minutes ago, knightslugger said:

i can make a cw radio that can be heard almost around the globe from radioshack parts bins in an altoids tin and a clothesline. don't tell me there's a lot of engineering and modeling that goes into RF electronics...

Yet again comparing apples to oranges. Analog continuous wave hf radio  is in no way similar to high data rate digital uhf connections used by phone companies. Just because you can scream loud enough to be heard miles away does not mean you can carry on a conversation at that distance. If its so easy you should just make your own router or cell tower.

 

[knightslugger]

23 minutes ago, bob345 said:

Yet again comparing apples to oranges. Analog continuous wave hf radio  is in no way similar to high data rate digital uhf connections used by phone companies. Just because you can scream loud enough to be heard miles away does not mean you can carry on a conversation at that distance. If its so easy you should just make your own router or cell tower.

 

the comparison was lost on you. while it is not a PERFECTLY ENGINEERED SOLUTION, it does in fact WORK. what we are talking about IN THIS THREAD is not a perfectly executed act of engineering.

[bob345]

6 minutes ago, knightslugger said:

what we are talking about IN THIS THREAD is not a perfectly executed act of engineering.

I am well aware, the fact still stands that a using a satellite tv dish as a reflector WILL NOT work as well as just using the proper standalone antenna in the first place which is what i have been saying. There is "working" and then there is just plain hopeless, dont mix up the two.