Antenna mounting recommendations for flat roof academic building
 

Hi there--

We've been given permission to mount a few antennas on the roof of one
of the buildings at school, with the only caveat being "don't make holes
in the roof."

We're looking at some yagis ( LPDA, about 12 feet long ) for VHF work,
and just need to get the things about 10-20 feet above the roof if possible.

Does anybody have any recommendations/tips on how to handle this? At
work, I've seen large steel mast mounts than lay flat on a roof to
support lightweight/low crosssection antennas... (yes, they're weighted
down with concrete blocks.) Where would I find such a beast? Our
facility manager has NO idea when these mast mounts wound up on the roof
at work.



Thanks.
-bill

(Replies to the group please)

We've always built our own, or rather had the welder do it. Steel tubing,
wall thickness determined by loading, weld an H and put the mast in the
middle of the cross bar. Lots of good outdoor enamel, and 4 or 8 unopened
sacks of ready mix for weights. It conforms to the tubing and roof surface,
and won't slide off like cinder blocks have been known to do. After a few
months in the weather they are solid blocks with just the right shape. Some
of our masts are 20 feet tall, but those are guyed to the tips of the "H".

--
Crazy George
Remove N O and S P A M imbedded in return address
"Bill Blum" wrote in message
m...
Hi there--

We've been given permission to mount a few antennas on the roof of one
of the buildings at school, with the only caveat being "don't make holes
in the roof."

We're looking at some yagis ( LPDA, about 12 feet long ) for VHF work,
and just need to get the things about 10-20 feet above the roof if
possible.

Does anybody have any recommendations/tips on how to handle this? At
work, I've seen large steel mast mounts than lay flat on a roof to
support lightweight/low crosssection antennas... (yes, they're weighted
down with concrete blocks.) Where would I find such a beast? Our
facility manager has NO idea when these mast mounts wound up on the roof
at work.



Thanks.
-bill

(Replies to the group please)

On Thu, 03 Jun 2004 22:33:14 GMT, Bill Blum
wrote:

Hi there--

We've been given permission to mount a few antennas on the roof of one
of the buildings at school, with the only caveat being "don't make holes
in the roof."

Check out this company's flat roof mounting system.

http://www.glenmartin.com/catalog/page155.html

DannY, k6mhe

Bill Blum wrote in message om...
Hi there--

We've been given permission to mount a few antennas on the roof of one
of the buildings at school, with the only caveat being "don't make holes
in the roof." ...
Hi Bill,
some hams use an old tyre as the base. They lay it flat on the roof. A
lumber or sheet-metal circle fills the center of the tyre. An approx.
0,5 m (2 ft) long tube is attached vertically in its center. (Do not
forget a small hole for rain water dripping.) The tyre is filled with
concrete then. When the concrete hardens, you have a heavy and sturdy
base for a tube mast. Only the rubber tyre is in contact with the
roof, so no damage should be done. You can roll the tyre on the roof
if you have to move it.
If you need a bigger mounting, use a tyre from a truck or several
smaller tyres. The same tyre base adopted for a rope or wire can be
used for attaching guy wires / ropes.

73 Ivan OK1SIP

If your school has a vo-tech department fabricating such mounts should be a
no-brainer for them.


"Bill Blum" wrote in message
m...
Hi there--

We've been given permission to mount a few antennas on the roof of one
of the buildings at school, with the only caveat being "don't make holes
in the roof."

We're looking at some yagis ( LPDA, about 12 feet long ) for VHF work,
and just need to get the things about 10-20 feet above the roof if
possible.

Does anybody have any recommendations/tips on how to handle this? At
work, I've seen large steel mast mounts than lay flat on a roof to
support lightweight/low crosssection antennas... (yes, they're weighted
down with concrete blocks.) Where would I find such a beast? Our
facility manager has NO idea when these mast mounts wound up on the roof
at work.



Thanks.
-bill

(Replies to the group please)

Jimmy wrote:
If your school has a vo-tech department fabricating such mounts should be a
no-brainer for them.

Nope-- we're a "liberal arts" university.

Found a few things at a local surplus shop that should work...

Try www.gordtelecom.com they have this product.

"Bill Blum" wrote in message
m...
Hi there--

We've been given permission to mount a few antennas on the roof of one
of the buildings at school, with the only caveat being "don't make holes
in the roof."

We're looking at some yagis ( LPDA, about 12 feet long ) for VHF work,
and just need to get the things about 10-20 feet above the roof if
possible.

Does anybody have any recommendations/tips on how to handle this? At
work, I've seen large steel mast mounts than lay flat on a roof to
support lightweight/low crosssection antennas... (yes, they're weighted
down with concrete blocks.) Where would I find such a beast? Our
facility manager has NO idea when these mast mounts wound up on the roof
at work.



Thanks.
-bill

(Replies to the group please)