Mofi 4500 with a signal amplifier?

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Gpine
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Mofi 4500 with a signal amplifier?

Post by Gpine »

I recently moved to a rural area with no cable or fiber so I went with fixed wireless. I am surrounded by tall trees with only a couple of areas that are clear. Trying to get above the trees is impractical since I would need at least a 60' pole. I am using a MOFI 4500 modem with a Bolton Long Ranger external antenna on the AT&T network. After playing around with the antenna outside, the best I can get is 3 bars on Band 2. This is good for around 25-30MBps download speed and around 20 MBps upload speed. Would adding a signal amplifier to get a better signal make a difference as far as download speeds go? Also, I am running 150' of low loss coax cable between the router and antenna. Does a cable that long affect the signal?
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Didneywhorl
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Re: Mofi 4500 with a signal amplifier?

Post by Didneywhorl »

Coax cable of any length, with RF signal use, effects signal for sure.

What quality/name cable are you using? This is very important.

Cellular RF is a oscillating frequency signal. This run over a cable creates an inductive reactance that acts like a resistor would in a DC circuit. (basically restricts the strength of the out flow). The longer the cable, the higher the resistance.

At 150 foot length you are basically killing a large amount of signal gain from your high powered antenna.


Examples:

You said you had Band 2 connected. Band two is at approximately 1900MHz.

If you have 150' foot of LMR200 equivalent cable and connected band 2, using the Bolton antenna, you are starting with approximately 24dBi of signal gain at the antennas connector. Over the 150' at 1900Mhz on ~LMR200 coax you will be left with about 2dBi (assume you replaced a set of 3 dBi omnis) leaves you with -1dBi of signal gain ignoring connector losses; which shouldn't be too much by its self. Terrible considering the cost of the antenna plus cabling. The only benefit here is that the antenna is up in the air getting a signal from the open air versus trying to pick it up through your walls.

https://www.timesmicrowave.com/Calculat ... uency=1900

If you have 150' foot of LMR400 equivalent cable and connected band 2, using the Bolton antenna, you are starting with approximately 24dBi of signal gain at the antennas connector. Over the 150' at 1900Mhz on ~LMR400 coax you will be left with about 14dBi (assume you replaced a set of 3 dBi omnis) leaves you with 11dBi of signal gain ignoring connector losses; which shouldn't be too much. Worst case you are left with about 8-10dBi of gain. That's no too bad but its not ~$300 +cable costs per antenna good.

https://www.timesmicrowave.com/Calculat ... uency=1900

If you have 150' foot of LMR600 equivalent cable and connected band 2, using the Bolton antenna, you are starting with approximately 24dBi of signal gain at the antennas connector. Over the 150' at 1900Mhz on ~LMR600 coax you will be left with about ~17dBi (assume you replaced a set of 3 dBi omnis) leaves you with ~14dBi of signal gain ignoring connector losses; which shouldn't be too much. Worst case you are left with about ~12-14dBi of gain. That's better but again its not ~$300 +cable costs per antenna good. Especially since LMR600 at 150' would be VERY EXPENSIVE.

https://www.timesmicrowave.com/Calculat ... uency=1900


If you connect to a higher frequency band the [gain] numbers get worse. Connect to a lower band the numbers improve a little.

Also, if you are using only one antenna you are crippling your modem. It works, but it will work MUCH better with a matched pair of antennas. I would go thiw router before placing $300-$800 in a booster system, which might end up with boosted noise and a low quality, though stronger, connection.

Boosters have a place, but they aren't a cornucopia of solution that the marketing for them would have you believe.
Dr-BroadBand
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Re: Mofi 4500 with a signal amplifier?

Post by Dr-BroadBand »

Would think 🤔 about using PoE
Power over ethernet and an enclosure for the MoFI.

Keep your antenna cable very short and cheap. LMR400

Use cat6a or cat7 cable for the data
Gpine
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Re: Mofi 4500 with a signal amplifier?

Post by Gpine »

I'm using Wilson electronics LMR400 cable. As far as the length of the cable, I don't have much choice there. My house is surrounded on 3 sides with tall trees and the only signal I can get is with the antenna pointing down the road. My house is about 100' from the road. I have tried it on band 12 as well with better signal but the speed is severely reduced.
Dr-BroadBand
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Re: Mofi 4500 with a signal amplifier?

Post by Dr-BroadBand »

Here are two examples of a PoE setup
The advantage of PoE you can keep the antenna wires very short.

The disadvantage is your modem is out in the heat and can overheat.
I have seen clever ways to over come the overheating

Bottom line is an amplifier is NOT going to help, and the length of your cables are going to kill what little signal you have.
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