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  #11   Report Post  
Old May 4th 04, 03:29 PM
Crazy George
 
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Default

Bill:

You need to enlist a little geometry and mechanical engineering. We like to
keep our top guys at 45 degrees or less (ground up to guy) where space
permits. The down force on the mast for each guy is then .707 of the guy
tension. As the guys get steeper, the down force on the mast becomes a
larger and larger portion of the total tension. So for a smaller
'footprint' with the guys near straight up, any side force on the guy from
wind or antenna tension becomes a larger down force on the mast. I need to
make drawings to clarify that point, so find someone mechanically inclined
to wave their hands and draw lines and make calculations for you.

As far as the stepladder on the roof, consider the average male is just
under 6' tall, with an 18" up reach. So he has to stand only 4 feet above
the mounting level of the base of the mast to erect it. A 5 foot stepladder
straddling the peak of most roofs is relatively stable if you are young,
limber and agile. Having the first (bottom) section SOLIDLY guyed is a
must. At least that's what I remember from the middle of the last century.

--
Crazy George
Remove N O and S P A M imbedded in return address
"zeno" wrote in message ...
Hi John,

For a 50' tall mast, what would you say would be the minimum acceptible

square
dimensions from vertices (on a flat plane with the base) of the guy wire

anchor
points?

Bill K6TAJ

John Moriarity wrote:

"zeno" wrote in message

...
How the heck did those TV crews of yesteryear erect 40+ foot
telescoping antenna masts sitting atop pointed roofs? Its not
exactly like you can set up a step ladder on such a roof to
get up the first 10 foot to pull up the rest of the sections.


That's exactly what we did! When you are
young and fearless and believe in your
personal immortality, it's amazing what
you can do ;-)

73, John - K6QQ




  #12   Report Post  
Old May 4th 04, 04:16 PM
Gary V. Deutschmann, Sr.
 
Posts: n/a
Default

Hi Bill

After a serious fall a number of years ago, I am now terrified of
heights like you wouldn't believe.

Yet I am still able to put up 50 foot towers, push-ups and even
sectional guyed poles by myself with no problems.

On push-up poles, I lay them on the ground first, open them up, make
point to point guy ring measurements, mark the poles for their maximum
safe expansion and close the assembly back up and haul it up to the
roof.

The main body is guyed and finished off prior to doing anything else.
Using the formula to find the hypoteneuse the guys are marked for full
length, then remarked for each lifting stage of the operation.

The antenna or antennas are affixed to the innermost or highest part
of the mast, which is only extended at this time long enough to do
this operation. The ladder to reach them is set on the roof and tied
to the now rigid base mast section.

Before lifting, the guys for section one are clamped at their first
set of markings, which allows a little slack or you couldn't lift it
to the proper fixed height. After the clamps are in place, as you
lift the first section, the guys slide through the eyes until they
near the clamp. The mast is only lifted about 2 feet at a time and
the standoffs for the ladder line are installed or the coax affixed to
the mast with ties. Again it is lifted another 2 feet and a standoff
or tie or both are installed. Repeated until you reach your 10 foot
marking and this top section is then locked down solid.

Now clamps are installed to the guys for section two to the first
marking, the clamps for section one are loosened and clamps installed
on the second marking for the upper guys.
Here is where it helps to have 3 or 4 extra helpers to feed guys and
keep them fairly taught. But if you don't have them, the pole is not
going to fall further than the next set of clamps on the guys, or
about a 2 to 3 foot lean at this early stage, the lean gets less as
the guys get longer.

The second mast is pushed up, usually by bouncing it so the first
clamps of the section one guys can slide on the cables but still have
enough tension to hold the antenna upright for you.
Again, working in 2 foot increments, the standoffs and/or ties are
installed.

By the time you get section two up to maximum height, you will not be
able to lift the remaining sections by hand. It's not the weight,
it's the tension on the guys and floating clamps that are your enemy.
If your familiar with how a Pony clamp set works, I had a similar tool
made for lifting push-pole sections. A clamp is affixed to pole two
and to the main mast in two places. I simply turn the handle to lift
the pole about 8 inches, then lock it down, crank the tool back down,
let it catch the pole and unlock the mast and crank it up another 8
inches and repeat until I get to the two foot point. Then I install
the standoffs and/or ties or both. Then repeat again.

Once the whole assembly is at full height, the guys are then tensioned
to their proper rating. If your guys are NOT equal distance from the
tower, you will have to make adjustments to the tension settings to
maintain a perfectly vertical pole.

Many of your guys themselves can be used as antennas if you plan for
this before setting up the system.

I put up an 80 foot vertical single handedly using only 1 inch 10 foot
sections of interconnecting pipes. We had intended going up 100 feet,
but the pipe was not strong enough to hold itself without telescoping
and splitting, so we halted at 80 feet. It stood for 9 years
untouched and without problems. Taking it down was really simple.
One hit to the lower pipe with a baseball bat and the whole thing came
straight down on itself and finally stopped dropping at about 15 feet
of height and leaned over, the antenna did not touch the ground and
was salvagable.

TTUL
Gary

  #13   Report Post  
Old May 4th 04, 05:46 PM
deje a lector guardarse
 
Posts: n/a
Default

I installed a Hy-Gain TH-3 Jr and an Alliance TV rotor on a 20 foot TV mast
on a 2 story house -- used a heavy duty antenna tripod for a base-- total
height 42 feet.

The drill was with 5 "Amateurs":
1. Under the roof -- installed 4 by 4's to take lag bolts from the Tripod
base
2. Bolted down the tripod mount to roof and 4x4's -- under the roof added
sealant to prevent water entering.
3. Raised collapsed TV mast with antenna rotor and 4 guy wires --secured in
tripod
4. Guyed the 10 foot section with the 4 guy wires
5. Set step ladder next to 10 foot guyed section -- secured ladder with rope
to mast
6. Stong buddy also held ladder against mast
7. Tall guy (me) ascends ladder. Had rope around my waist in case I nose
dived off of the ladder
8. Horsed the collapsed section with 4 more guy wires attached -- up to 20
feet - secured guy wires (Total 8 guy wires)
9. Fed all hands Pizza and beer.
10. Antenna stayed up there thru storms winds et al for 15 years before I
moved.

Your installation may vary -- this is just the way we did it -- but we were
are not professional installers, so caveat installer. I take no
responsibility for your installation.

You should contact professional TV antenna installers for their approval --
or better yet -- let them install it.


--
deje a lector guardarse

Amateur Radio is the best back-up
communications system in the world,
and that's the way it is. Walter Cronkite





"John Moriarity" wrote in message
...
How did you secure a step ladder on the peak of a roof?


Well, If you're still somewhat chicken,
you can enlist another person to foot
the ladder ;-)

73, John - K6QQ




  #14   Report Post  
Old May 4th 04, 05:57 PM
zeno
 
Posts: n/a
Default

Hi George,

A 45 degree angled guy from the top of a 50' tall mast will be out 50' from the
base of the mast. That would suggest that the "square" made from the four
anchor points is 100' on a side. I will have to look at the site and see if
that is possible.

Bill

Crazy George wrote:

Bill:

You need to enlist a little geometry and mechanical engineering. We like to
keep our top guys at 45 degrees or less (ground up to guy) where space
permits. The down force on the mast for each guy is then .707 of the guy
tension. As the guys get steeper, the down force on the mast becomes a
larger and larger portion of the total tension. So for a smaller
'footprint' with the guys near straight up, any side force on the guy from
wind or antenna tension becomes a larger down force on the mast. I need to
make drawings to clarify that point, so find someone mechanically inclined
to wave their hands and draw lines and make calculations for you.

As far as the stepladder on the roof, consider the average male is just
under 6' tall, with an 18" up reach. So he has to stand only 4 feet above
the mounting level of the base of the mast to erect it. A 5 foot stepladder
straddling the peak of most roofs is relatively stable if you are young,
limber and agile. Having the first (bottom) section SOLIDLY guyed is a
must. At least that's what I remember from the middle of the last century.

--
Crazy George
Remove N O and S P A M imbedded in return address
"zeno" wrote in message ...
Hi John,

For a 50' tall mast, what would you say would be the minimum acceptible

square
dimensions from vertices (on a flat plane with the base) of the guy wire

anchor
points?

Bill K6TAJ

John Moriarity wrote:

"zeno" wrote in message

...
How the heck did those TV crews of yesteryear erect 40+ foot
telescoping antenna masts sitting atop pointed roofs? Its not
exactly like you can set up a step ladder on such a roof to
get up the first 10 foot to pull up the rest of the sections.

That's exactly what we did! When you are
young and fearless and believe in your
personal immortality, it's amazing what
you can do ;-)

73, John - K6QQ



  #15   Report Post  
Old May 4th 04, 06:07 PM
zeno
 
Posts: n/a
Default

Hi Gary,

Thanks for the thorough instructions. I am not sure I understand the pony
clamp, but I agree that I can see a problem trying to lift up the
combined weight of the last 4 of the 5 sections after the first 10 foot
section is in place. Where can I see an image of such a "pony clamp"? I
have two people trying to pull it up maybe it can be done by hand.

Bill

"Gary V. Deutschmann, Sr." wrote:

Hi Bill

After a serious fall a number of years ago, I am now terrified of
heights like you wouldn't believe.

Yet I am still able to put up 50 foot towers, push-ups and even
sectional guyed poles by myself with no problems.

On push-up poles, I lay them on the ground first, open them up, make
point to point guy ring measurements, mark the poles for their maximum
safe expansion and close the assembly back up and haul it up to the
roof.

The main body is guyed and finished off prior to doing anything else.
Using the formula to find the hypoteneuse the guys are marked for full
length, then remarked for each lifting stage of the operation.

The antenna or antennas are affixed to the innermost or highest part
of the mast, which is only extended at this time long enough to do
this operation. The ladder to reach them is set on the roof and tied
to the now rigid base mast section.

Before lifting, the guys for section one are clamped at their first
set of markings, which allows a little slack or you couldn't lift it
to the proper fixed height. After the clamps are in place, as you
lift the first section, the guys slide through the eyes until they
near the clamp. The mast is only lifted about 2 feet at a time and
the standoffs for the ladder line are installed or the coax affixed to
the mast with ties. Again it is lifted another 2 feet and a standoff
or tie or both are installed. Repeated until you reach your 10 foot
marking and this top section is then locked down solid.

Now clamps are installed to the guys for section two to the first
marking, the clamps for section one are loosened and clamps installed
on the second marking for the upper guys.
Here is where it helps to have 3 or 4 extra helpers to feed guys and
keep them fairly taught. But if you don't have them, the pole is not
going to fall further than the next set of clamps on the guys, or
about a 2 to 3 foot lean at this early stage, the lean gets less as
the guys get longer.

The second mast is pushed up, usually by bouncing it so the first
clamps of the section one guys can slide on the cables but still have
enough tension to hold the antenna upright for you.
Again, working in 2 foot increments, the standoffs and/or ties are
installed.

By the time you get section two up to maximum height, you will not be
able to lift the remaining sections by hand. It's not the weight,
it's the tension on the guys and floating clamps that are your enemy.
If your familiar with how a Pony clamp set works, I had a similar tool
made for lifting push-pole sections. A clamp is affixed to pole two
and to the main mast in two places. I simply turn the handle to lift
the pole about 8 inches, then lock it down, crank the tool back down,
let it catch the pole and unlock the mast and crank it up another 8
inches and repeat until I get to the two foot point. Then I install
the standoffs and/or ties or both. Then repeat again.

Once the whole assembly is at full height, the guys are then tensioned
to their proper rating. If your guys are NOT equal distance from the
tower, you will have to make adjustments to the tension settings to
maintain a perfectly vertical pole.

Many of your guys themselves can be used as antennas if you plan for
this before setting up the system.

I put up an 80 foot vertical single handedly using only 1 inch 10 foot
sections of interconnecting pipes. We had intended going up 100 feet,
but the pipe was not strong enough to hold itself without telescoping
and splitting, so we halted at 80 feet. It stood for 9 years
untouched and without problems. Taking it down was really simple.
One hit to the lower pipe with a baseball bat and the whole thing came
straight down on itself and finally stopped dropping at about 15 feet
of height and leaned over, the antenna did not touch the ground and
was salvagable.

TTUL
Gary




  #16   Report Post  
Old May 4th 04, 08:06 PM
Dave Shrader
 
Posts: n/a
Default

Only three guys are needed. Your 100 foot number may be in error.

How about 75 feet between anchors in a three guy wire system?

zeno wrote:

Hi George,

A 45 degree angled guy from the top of a 50' tall mast will be out 50' from the
base of the mast. That would suggest that the "square" made from the four
anchor points is 100' on a side. I will have to look at the site and see if
that is possible.

Bill

Crazy George wrote:


Bill:

You need to enlist a little geometry and mechanical engineering. We like to
keep our top guys at 45 degrees or less (ground up to guy) where space
permits. The down force on the mast for each guy is then .707 of the guy
tension. As the guys get steeper, the down force on the mast becomes a
larger and larger portion of the total tension. So for a smaller
'footprint' with the guys near straight up, any side force on the guy from
wind or antenna tension becomes a larger down force on the mast. I need to
make drawings to clarify that point, so find someone mechanically inclined
to wave their hands and draw lines and make calculations for you.

As far as the stepladder on the roof, consider the average male is just
under 6' tall, with an 18" up reach. So he has to stand only 4 feet above
the mounting level of the base of the mast to erect it. A 5 foot stepladder
straddling the peak of most roofs is relatively stable if you are young,
limber and agile. Having the first (bottom) section SOLIDLY guyed is a
must. At least that's what I remember from the middle of the last century.

--
Crazy George
Remove N O and S P A M imbedded in return address
"zeno" wrote in message ...

Hi John,

For a 50' tall mast, what would you say would be the minimum acceptible


square

dimensions from vertices (on a flat plane with the base) of the guy wire


anchor

points?

Bill K6TAJ

John Moriarity wrote:


"zeno" wrote in message


...

How the heck did those TV crews of yesteryear erect 40+ foot
telescoping antenna masts sitting atop pointed roofs? Its not
exactly like you can set up a step ladder on such a roof to
get up the first 10 foot to pull up the rest of the sections.

That's exactly what we did! When you are
young and fearless and believe in your
personal immortality, it's amazing what
you can do ;-)

73, John - K6QQ



  #17   Report Post  
Old May 4th 04, 10:57 PM
Jim Kelley
 
Posts: n/a
Default



Dave Shrader wrote:

Only three guys are needed. Your 100 foot number may be in error.


100 feet would be the correct number if it was a two guy wire system.
Right? :-)

73, ac6xg

How about 75 feet between anchors in a three guy wire system?

zeno wrote:

Hi George,

A 45 degree angled guy from the top of a 50' tall mast will be out 50' from the
base of the mast. That would suggest that the "square" made from the four
anchor points is 100' on a side. I will have to look at the site and see if
that is possible.

Bill

Crazy George wrote:


Bill:

You need to enlist a little geometry and mechanical engineering. We like to
keep our top guys at 45 degrees or less (ground up to guy) where space
permits. The down force on the mast for each guy is then .707 of the guy
tension. As the guys get steeper, the down force on the mast becomes a
larger and larger portion of the total tension. So for a smaller
'footprint' with the guys near straight up, any side force on the guy from
wind or antenna tension becomes a larger down force on the mast. I need to
make drawings to clarify that point, so find someone mechanically inclined
to wave their hands and draw lines and make calculations for you.

As far as the stepladder on the roof, consider the average male is just
under 6' tall, with an 18" up reach. So he has to stand only 4 feet above
the mounting level of the base of the mast to erect it. A 5 foot stepladder
straddling the peak of most roofs is relatively stable if you are young,
limber and agile. Having the first (bottom) section SOLIDLY guyed is a
must. At least that's what I remember from the middle of the last century.

--
Crazy George
Remove N O and S P A M imbedded in return address
"zeno" wrote in message ...

Hi John,

For a 50' tall mast, what would you say would be the minimum acceptible

square

dimensions from vertices (on a flat plane with the base) of the guy wire

anchor

points?

Bill K6TAJ

John Moriarity wrote:


"zeno" wrote in message

...

How the heck did those TV crews of yesteryear erect 40+ foot
telescoping antenna masts sitting atop pointed roofs? Its not
exactly like you can set up a step ladder on such a roof to
get up the first 10 foot to pull up the rest of the sections.

That's exactly what we did! When you are
young and fearless and believe in your
personal immortality, it's amazing what
you can do ;-)

73, John - K6QQ


  #18   Report Post  
Old May 4th 04, 11:59 PM
zeno
 
Posts: n/a
Default

With four guys the distance between any two 180 degree opposing guys will be 100' at
the base level. That is why I said that four guys at 45 degree angle at the top of a
50' mast will make a square at the four anchor points and that square at the base
level is 100' on each side. I am thinking that 30 degrees at the top might be fine for
my project in which case a smaller square.

Bill - K6TAJ


Jim Kelley wrote:

Dave Shrader wrote:

Only three guys are needed. Your 100 foot number may be in error.


100 feet would be the correct number if it was a two guy wire system.
Right? :-)

73, ac6xg

How about 75 feet between anchors in a three guy wire system?

zeno wrote:

Hi George,

A 45 degree angled guy from the top of a 50' tall mast will be out 50' from the
base of the mast. That would suggest that the "square" made from the four
anchor points is 100' on a side. I will have to look at the site and see if
that is possible.

Bill

Crazy George wrote:


Bill:

You need to enlist a little geometry and mechanical engineering. We like to
keep our top guys at 45 degrees or less (ground up to guy) where space
permits. The down force on the mast for each guy is then .707 of the guy
tension. As the guys get steeper, the down force on the mast becomes a
larger and larger portion of the total tension. So for a smaller
'footprint' with the guys near straight up, any side force on the guy from
wind or antenna tension becomes a larger down force on the mast. I need to
make drawings to clarify that point, so find someone mechanically inclined
to wave their hands and draw lines and make calculations for you.

As far as the stepladder on the roof, consider the average male is just
under 6' tall, with an 18" up reach. So he has to stand only 4 feet above
the mounting level of the base of the mast to erect it. A 5 foot stepladder
straddling the peak of most roofs is relatively stable if you are young,
limber and agile. Having the first (bottom) section SOLIDLY guyed is a
must. At least that's what I remember from the middle of the last century.

--
Crazy George
Remove N O and S P A M imbedded in return address
"zeno" wrote in message ...

Hi John,

For a 50' tall mast, what would you say would be the minimum acceptible

square

dimensions from vertices (on a flat plane with the base) of the guy wire

anchor

points?

Bill K6TAJ

John Moriarity wrote:


"zeno" wrote in message

...

How the heck did those TV crews of yesteryear erect 40+ foot
telescoping antenna masts sitting atop pointed roofs? Its not
exactly like you can set up a step ladder on such a roof to
get up the first 10 foot to pull up the rest of the sections.

That's exactly what we did! When you are
young and fearless and believe in your
personal immortality, it's amazing what
you can do ;-)

73, John - K6QQ



  #19   Report Post  
Old May 5th 04, 02:24 AM
Dave Shrader
 
Posts: n/a
Default

Jim Kelley wrote:


Dave Shrader wrote:

Only three guys are needed. Your 100 foot number may be in error.



100 feet would be the correct number if it was a two guy wire system.
Right? :-)

73, ac6xg


Yep! And the guys would provide an unconditionally unstable system.

  #20   Report Post  
Old May 5th 04, 02:30 AM
Dave Shrader
 
Posts: n/a
Default

Bill, that's correct. But, most guying systems are only 3 wires on a 120
degree spread at 45 degrees from the anchor on the tower/mast. That
requires only 75 feet. A three wire system is a STABLE solution. A four
wire system is also a stable system.

BTW, I used to have a Rohn 25 system at 50 feet. Rohn recommended double
guying. First level at the 30 foot height. Second level just below the
rotator platform. Point I'm making is that one set of guys at the 50
foot level may not meet Zoning and Insurance safety requirements.

Deacon Dave, W1MCE

zeno wrote:

With four guys the distance between any two 180 degree opposing guys will be 100' at
the base level. That is why I said that four guys at 45 degree angle at the top of a
50' mast will make a square at the four anchor points and that square at the base
level is 100' on each side. I am thinking that 30 degrees at the top might be fine for
my project in which case a smaller square.

Bill - K6TAJ


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