Not exactly ham radio...but close

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Recently my Verizon DSL went out and even though its back its far slower than before and I'm pretty sick of it. I have come up with a hair brained scheme to get broadband without DSL.

[The plan]
Put a cell modem on the top of a nearby hill and create a point to point link to my house.

[Background]
This morning I hiked to the top of the hill that is 1212ft elevation. With my iPhone I have confirmed that I can get 35/10MB bandwidth over LTE. Distance from this location to my house is roughly 1800ft. My house is at 1003ft elevation. The top of the hill has been recently logged but still has quite a lot of tree cover. Since the hill drops 200ft the tree cover is not solid for the entire 1800ft. There will be some trees on the way then open air and then trees on my property. I can play with the location of the receiving radio to bypass some tree cover.

[A possible solution]
Cell modem connected to a Ubiquiti NanoBeam with a second NanoBeam at the house. These come in 2.4 and 5ghz (2.4 most likely due to trees). Power required would be less than 20 watts. I can run 1800ft of low voltage landscape lighting "over the river and thru the woods". If I pump 36v down the wire and filter it with a buck/boost DC/DC converter I should be able to make a clean 12vdc.

This is a "stealth" installation so PV panels are out.

Any thoughts, ideas on cheaper equipment, etc etc?
 
If you're going to drag power all that way, why not pull fiber and eliminate the PtP Wireless. You'll get better throughput and won't have to worry about line of sight.
 
2000' of 16 awg is about 16 ohms (4 ohms/1000') round trip
You will need to crank the voltage up to at least 40v which will allow a surge up to about 25 watts - 48 volts would be best

2000' of 14 awg - 10 ohms: Will support a surge up to 32 watts at 36 volts
 
The skywire guys started out doing what I am proposing. Putting wireless gear at the tops of hills and beaming signals to and fro. I think they now have fiber on lots of hilltops now. I was at Lopstick this summer and was seeing 10M down consistently...they use Skywire.

I'm not sure on the fiber idea. I think its awfully expensive. I'm just gonna run cables across the forest floor and a fiber that is somewhat ruggedized is pretty expensive. If low voltage lighting cable gets cut who cares, fiber its a pain in the ass.

Pastera, looking at the price of wire I'm thinking smaller wire and higher voltage will be the way to go. A 36-48 volt power supply with a quality dc/dc converter at the business end I think will be fine. The cell modem and wifi radio will be using 20 watts max....some losses but manageable.

For the wifi link I'm thinking about using these: NanoBeam 2AC 13

For the modem this looks good (expensive tho): Pepwave MAX BR1 Mini with Cat 6 LTE Advanced Modem
 
In northern NH, we have an ISP called Skywire TCC that provides direct wireless even out in the boonies.
How are they? Charter's website says they can give us service, but (a) no gear on the poles, and (b) when I asked at the office in town, they said flat-out NO.
 
What are you doing to prevent a hilltop lightning strike from
channeling down the (copper vapor of the former) power wires
and burning your house to the ground?

Because the second you turn your back on the setup,
it'll totally do that, you know.

I have to wonder whether it's safe to unroll 600 yards of wire
in leaf litter. Hikers caught above tree-line in a thunderstorm
are told to squat with their feet together so that if there's a
discharge running over the surface of the ground, to minimize
the chance that a fraction of the current will divert up one leg,
through their heart, and back down the other leg. Don't know
whether that can happen or whether squatting with your feet
together minimizes the risk, but it's a tale handed out all the time.

If a stroke was dissipating along the ground and encountered
your insulated power cable, what are the odds it would
bang a left at Albuquerque and zap your house?
=====
Over a decade ago I read the story of some ham outside of LA
who got broadband before his street was wired.

He lived up one of those canyons carved into the side of the hills overlooking the basin.
He could see the twinkling lights of the houses down on the flats (who had broadband),
and realized that he could establish a radio link to them. So he used a telescope to identify
the specific houses that were line-of-sight, and then started knocking on doors.
Told the homeowners, "let me wire a radio repeater on your chimney pointed up the hill,
and I'll pay half your broadband bill every month".

It wasn't long before he found a taker for the offer.
Worked like a charm.


Sorry for the negative vibes, but Zeus don't play games.

My Elmer's house in Chatham suffered a strike
that blew up everything attached to his wired Ethernet.
(And nothing else).
Including an HF rig priced in the high 4-figures.

At least it didn't burn the house down,
but I suspect losing that radio
dwarfed any damage to computers or smart TVs.
 
In VT, one can get 'over the air' WIFI at a low cost. It isn't the regular LTE. It is a different frequency and travels further. It works well at our remote camp (LTE service is sketchy). Anyway, there might be an alternate solution available to you depending on your area.
 
How are they? Charter's website says they can give us service, but (a) no gear on the poles, and (b) when I asked at the office in town, they said flat-out NO.
Friends who use them have had mixed results, but once they get it running right (and they do bust ass to make it right), they're great.

I'm in the village on Spectrum cable (TWC). From what I've read, Skywire is mostly north of US-2.
 
I'm with the others.. if ya gotta run power anyway, just run a wire too. That's a long haul for copper, but marginally doable cheap. It's a trivial run for fiber.

You can probably do it using some multimode/single mode converters and dirt cheap fiber using 2005 era kit surplussed off eBay for way under any of the modern wireless beam tech gizmos.

I'd have to look it up again, but I think you can still get 100mbps over cat6 at that distance.

Edited: fine I looked it up.

Utp and coax are options. I think in your case I would run coax. Not sure why, but it feels less iky:

LRP-101C-KIT 1-Port Long Reach PoE over coax Extender would get you where ya need to go.
 
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I was looking something like that.....was thinking I would need to roll my own. I am also considering a PV panel surge arrestor at the power supply (pretty beefy piece)...I have one sitting in a junk box someplace.

All the power is being fed into a dc/dc converter that is isolated, it should sacrifice itself and protect the electronics....$60 is better than $500.

 
I have not seen any fiber that can handle being run across the forest floor for less than $2/ft. Can you point me to something suitable? I have never done any work with fiber.

I was up on the hill this afternoon taking signal readings. I do have concerns about getting a 2.4 ghz signal thru the trees. The actual distance is only 1/4 mile. The top of the hill has thin tree cover since its been logged recently, however I cannot see any point on my property. I'm guessing that I have about 200ft of fairly thin tree cover and the signal will be clear until it gets to the bank of tree in front of my house. I may run a cat5/6 to the edge of the road and mount the receiver dish there. This might be a little finicky...

OTOH, if I can find ~1800ft of fiber cheap enough I have no issues going that route either!

If the fiber is cheap enough I suppose it could be ruggedized by running it thru plastic air hose?

I'm with the others.. if ya gotta run power anyway, just run a wire too. That's a long haul for copper, but marginally doable cheap. It's a trivial run for fiber.

You can probably do it using some multimode/single mode converters and dirt cheap fiber using 2005 era kit surplussed off eBay for way under any of the modern wireless beam tech gizmos.

I'd have to look it up again, but I think you can still get 100mbps over cat6 at that distance.
 
Max range for POE is 100M.

600M is way too far for DC IMO, especially a low current application. Usually people run as high a voltage and current as possible for long runs to keep efficiency up. Voltage drop is proportional to current running through it. Remember, 600M of DC provides 1200M of voltage drop.

By my calculation you would need 9 gauge cable to make 1A at 12V available, and still have a 1.2V and 1.1A drop at that range. 8GA 2 conductor OUTDOOR!!! wire is $1.65 a foot or so, so you're looking at $3k in wire alone. You can get cheapo Chinese stuff for about half of that, but I had a bad experience so do what you will. You could push it and run 12AWG, have more voltage drop, still $1.20 a foot. You'd need a 13.5V PSU with 6A available to be able to handle startup load for 1A safely. And DC is pretty sensitive to temp changes too.

And PTP wifi links are all kind of wonky in bad weather. If you were a commercial client, I'd have to recommend 600M of legal subterranean AC, and a good PTP uplink. Since you're not commercial, it may or may not even work, just please be safe and avoid any electrical code SNAFUs. It might work, but the startup draw of a cold device on cold wire is beyond my ability to calculate at that range. Maybe Kim could help?
 
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Actually the power consumption is 20W @ 24vdc max (modem and wifi transmitter). Plan would be to run it from a 48v DC power supply that feeds a really nice DC/DC converter.

Using 16 awg landscape wire the resistance would be somewhere around 12 ohms. The current down the wire would be 410mA and you should see less than 10 volts loss across the wire. The DC/DC converter is a buck/boost style and should be able to handle some pretty poor input power (think its rated 12-72vdc input and 24v output).

I did a bunch of reading on the fiber thing again and I'm still not convinced its a good idea. The wifi radios are $99 I which is cheap enough to try out.

My backup plan If I cant get thru the trees is a series of short haul PTP links using cheap mesh network devices. I know for sure that I can go the first 1000-1200ft using the nanobeam (perfect LOS). From there its 600ft down the hill thru the woods. Three cheap mesh network devices should be able to span 200ft each. Maybe attach them about 10ft up on pine trees or something.

By my calculation you would need 9 gauge cable to make 1A at 12V available, and still have a 1.2V and 1.1A drop at that range. 8GA 2 conductor OUTDOOR!!! wire is $1.65 a foot or so, so you're looking at $3k in wire alone. You can get cheapo Chinese stuff for about half of that, but I had a bad experience so do what you will. You could push it and run 12AWG, have more voltage drop, still $1.20 a foot. You'd need a 13.5V PSU with 6A available to be able to handle startup load for 1A safely. And DC is pretty sensitive to temp changes too.
 
Actually the power consumption is 20W @ 24vdc max (modem and wifi transmitter). Plan would be to run it from a 48v DC power supply that feeds a really nice DC/DC converter.

Using 16 awg landscape wire the resistance would be somewhere around 12 ohms. The current down the wire would be 410mA and you should see less than 10 volts loss across the wire. The DC/DC converter is a buck/boost style and should be able to handle some pretty poor input power (think its rated 12-72vdc input and 24v output).

You know, I don't normally think solar power for anything because I'm a cheapskate and I loathe the thought of buying in to some particular tech. two months before we hit the knee in the efficiency curve. I don't want to be in the situation where what was the new hotness last month is now old and busted because solar cell design has made One Weird Change that now results in power "too cheap to meter".

But are your hilltop power requirements low enough that a solar panel and a deep discharge truck battery will get the job done with no electrical wiring needed through the woods? Who cares if a $250 system this month is $10 next month if it obviates $500 in wiring (and means you can't burn your house down as long as you use fiber or wireless for the data link).
 
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I ran the calculations (Off Grid System Calculator) and its a 250watt PV panel and a 250AH battery bank which gets me 2 days of reserve in winter.

I do have 200w of PV and 200ah golf cart batteries in my barn collecting dust. It turns this into a not so stealthy install...an option for sure. Many WISP's have remote nodes that are solar powered.

You know, I don't normally think solar power for anything because I'm a cheapskate and I loathe the thought of buying in to some particular tech. two months before we hit the knee in the efficiency curve. I don't want to be in the situation where what was the new hotness last month is now old and busted because solar cell design has made One Weird Change that now results in power "too cheap to meter".

But are your hilltop power requirements low enough that a solar panel and a deep discharge truck battery will get the job done with no electrical wiring needed through the woods? Who cares if a $250 system this month is $10 next month if it obviates $500 in wiring (and means you can't burn your house down if you use fiber or wireless).
 
I ran the calculations (Off Grid System Calculator) and its a 250watt PV panel and a 250AH battery bank which gets me 2 days of reserve in winter.

I do have 200w of PV and 200ah golf cart batteries in my barn collecting dust. It turns this into a not so stealthy install...an option for sure. Many WISP's have remote nodes that are solar powered.
Between preppers storing all their ammo underneath their back yard,
and the insane lengths our ham club's fox hunters through to bury
their transmitters in hollow trees bermed with tick-infested forest duff,
I'm sure you could hide the controller and battery just fine.

The panel - well, your mileage may vary.
Certainly paint any aluminum borders with flat brown paint.
 
I do agree its an option.

I will cross the bridge of how to power it once I see it working.

Between preppers storing all their ammo underneath their back yard,
and the insane lengths our ham club's fox hunters through to bury
their transmitters in hollow trees bermed with tick-infested forest duff,
I'm sure you could hide the controller and battery just fine.

The panel - well, your mileage may vary.
Certainly paint any aluminum borders with flat brown paint.
 
I used to run a number of mesh APs with PV panels and deep cycle batteries. This will not be a stealth install. 3'x3' panel that needs clear sunlight most of the day and the battery will get you about 18 hours, provided the other 6 are good clear sunlight with no shadows. This isn't a theoretical numbers thing, this is real world mesh network with Ruckus APs (21 solar in the system).
 
Actually the power consumption is 20W @ 24vdc max (modem and wifi transmitter). Plan would be to run it from a 48v DC power supply that feeds a really nice DC/DC converter.

Using 16 awg landscape wire the resistance would be somewhere around 12 ohms. The current down the wire would be 410mA and you should see less than 10 volts loss across the wire. The DC/DC converter is a buck/boost style and should be able to handle some pretty poor input power (think its rated 12-72vdc input and 24v output).

I did a bunch of reading on the fiber thing again and I'm still not convinced its a good idea. The wifi radios are $99 I which is cheap enough to try out.

My backup plan If I cant get thru the trees is a series of short haul PTP links using cheap mesh network devices. I know for sure that I can go the first 1000-1200ft using the nanobeam (perfect LOS). From there its 600ft down the hill thru the woods. Three cheap mesh network devices should be able to span 200ft each. Maybe attach them about 10ft up on pine trees or something.

if you need 20 watts at 24 volts -> assuming worst case IR drop leaves you with only 24 volts at the converter so the current is 0.833 amps
2000' of wire is 4000' of IR drop (16 awg is 4 ohms/1k') - 0.833 amps * 16 ohms = 13.333 volts of IR drop

The minimum voltage you can run is ( 24v + 13.3v) = 37.33 volts (you need to up the voltage for start up surge and regulator drop out)
 
Sounds about right. The DC/DC converter will tolerate less than 24 volts on the input. The 20 watt figure is probably 20% higher than actual. The 48 volt supply can be tweaked up to 54. The 2000ft wire run is likely to be more like 1500.

I think there is plenty of margin if I need it. My fallback position can be to supply the thing with 60 volts if for some reason I need to power something else.

if you need 20 watts at 24 volts -> assuming worst case IR drop leaves you with only 24 volts at the converter so the current is 0.833 amps
2000' of wire is 4000' of IR drop (16 awg is 4 ohms/1k') - 0.833 amps * 16 ohms = 13.333 volts of IR drop

The minimum voltage you can run is ( 24v + 13.3v) = 37.33 volts (you need to up the voltage for start up surge and regulator drop out)
 
Sounds about right. The DC/DC converter will tolerate less than 24 volts on the input. The 20 watt figure is probably 20% higher than actual. The 48 volt supply can be tweaked up to 54. The 2000ft wire run is likely to be more like 1500.

I think there is plenty of margin if I need it. My fallback position can be to supply the thing with 60 volts if for some reason I need to power something else.

You can't load side boost your way out of an IR drop problem but @ 60v supply, 12 ohms line resistance into a 24v load you can get 3 amps or 72 watts
 
More research sparked on by the calls to try fiber posted here. I have been reading into ethernet extenders. In short there are magic boxes that convert ethernet into VDSL and you can run 3000ft to something like a cell phone modem. Here is a place that makes them here in the US: Ethernet Extender PoE Extender Industrial Coax Custom Secure Enable-IT.

I have also been looking into the cable I will need to power this thing. It seems Cat5 direct bury cable is the nearly same price as low voltage landscape lighting. The 23awg variety is 20.3 ohms/K, using 4 pairs would net 5 ohms/K, and 3 pairs would net 6.8ohms/k. 16 awg landscape lighting is 4 ohms/k.

Using cat5 cable gives me the option to switch over to an ethernet extender if the wifi beam is not reliable. The ethernet extender has the added advantage of being a very stealthy installation. The location of the cell modem is not very critical...pretty much a camo box attached 12ft up a tree. I bet most people would not even notice it.
 
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