Railfan Technology > Radio Tower for potential web feed

We're looking at finding a new site (preferably up on a hill) to put a new radio feed for the area at. We've had pretty good success sitting on the hill and receiving 25+ miles in each direction without a problem. I'd like to put up a collapsible tower (50+ foot high total, pulley system to swing top side down in case of maintenance or other issues) with a cabinet mounted to the base for the radio equipment and such. Anyone have some info on where to get started with a project like this? I know a lot of rail fans also double as amateur radio operators too (Well, most of you are older guys, haha) so I would say someone has played with the idea before. And if I do do it, I definitely want to do it the right way.

http://www.kwindustries.com/LoginMenu.asp

This is a light pole manufacturer. Look @ their tapered hinged steel poles. 40 ft is their max but reasonable.

You have to register to view their on-line catalog but it's worth it.

RailNet802, over

There are 2 basic forms available:

"Crank-up" towers such as http://www.ustower.com/

"Fold-over" towers such as http://glenmartin.com/products-2/telecom-towers/fold-over-towers

Some considerations.

The equipment box and tower will be attacked by rodents both 4 and 2 legged, the latter with intent to steal or destroy.

You may incur liability related to the tower as an "attractive nuisance."

Your plans may require FCC approval, even if the tower is not used for transmitting, if it can be determined it may change the
antenna pattern of any existing stations.

You may also have the unparalleled delight of dealing with the FAA if the tower is close enough to an airport landing path.

Locating a tower will involve the local municipality and the agenda-driven political hacks on various permitting panels. Prepare yourself
for the onslaught of the "tin foil hat" - conspiracy - NIMBY crowd at public meetings.

Prepare to hire a professional engineer (PE) to go over the plans and affix his or her stamp. Bring your checkbook.


An alternative would be to locate an amateur radio repeater site and see if they will let you use their facilities for your radio and antenna.

This will require filters on your equipment as the 2 meter ham radio band is close enough that a station transmitting from the same facility
would interfere with RR band receivers.


Getting a place on an existing commercial tower may involve hiring a licensed, bonded, insured, certified tower climber. Permission from your cardiologist may be required before getting a quote for this work. Then there is the monthly tower rent and a litany of fees and charges.

Be Well,

Tim Colbert K3HX

Celebrating 50 years in amateur radio.

30+ years in the 2-way radio business.



Edited 1 time(s). Last edit at 01/21/15 09:35 by K3HX.

If you can receive well on the hill already, an extra 50' of tower isn't needed at all.

K3HX Wrote:
-------------------------------------------------------
> The equipment box and tower will be attacked by
> rodents both 4 and 2 legged, the latter with
> intent to steal or destroy.
>
> You may incur liability related to the tower as an
> "attractive nuisance."

Yep. That's why I never erected the 60 ft. crank-up tower I bought at a good price. About the same time some yo-yo had climbed a similar tower & hanged himself.

RailNet802, out
de KK5OL

Agree with K3HX 's comments. A friend found out the hard way, including a few more government entities due to complaints from neighbors. Eventually reduced his tower height substantially and his project worked just fine. For monitoring a hilltop works great anyways, additional height may not be advantageous, also as stated above.

You said you were on a hilltop to begin with but you didn't say anything about how high that hilltop was above average terrain. There is a fairly simple formula to "estimate" coverage based on distance to the horizon. It's a good ballpark guestimater.
Distance in miles is = SQR(1.5 x height in feet)

If you were on a hill 100 feet above average terrain your coverage might be about 12 miles but if you went up another 100 feet you might expect it to increase to about 17 miles, about a 40% improvement. (BTW, I'm talking about the distance to the horizon. The height of the other antenna is also part of the equation. Other propagation factors will also effect your range.)

If the hill is 500 feet above average terrain, you coverage would be about 27 miles. If you increase the height by 100 feet you coverage would increase to about 30 miles. about an 11% improvement. There would be another thing to consider with that increased height, the additional loss in the coaxial feedline.

Lets run this in case you are already on a really tall hill, say 2000 feet. Your distance to the horizon would be nearly 55 miles. Add another 250 feet and the horizon is now 58 miles out, an increase of 2%, minus the feedline losses.

If you already have decent coverage on the hilltop, I might go up 20 feet on a piece of "fence toprail" to get away from any clutter that seems to hover around the ground but unless you really need the extra coverage, I probably wouldn't spend $500 or $1000 or more to gain an additional 50 feet.

John