My 40m went up in a similar way.
The pro antenna crew (Paul's crew @ Custom Metal Works) trammed 350# 48
ft boom 3L 40m to 140' on a Rohn 65, back guyed with EHS the 3" alloy
mast at 155ft as the tram line tower end. Ground end was to a Kubota
B3200 tractor (3k#?) to tension the 7x19 tram cable, I don't remember
size. Double pulley on the tram to spread the load, capstan at tower
base with 5/8 line. Antenna start point about 130ft from tower base.
Max back position of Kubota about 230ft. Several come-a-longs and two
men to jockey the antenna into the ring rotator mount. This was the
last of 7 beams trammed onto this tower this way (tram line was lower
for others). A movable tram anchor was very helpful.
So it is doable. However, the 80m 2L 350# above it at 157ft went there
with a crane. Steps bolted on the mast. MUCH easier & safer. Worth
every shilling if you can make it work.
I see you are doing the arithmetic, don't forget the further back the
tram position, the higher the lateral tower load and the more the
catenary sag. With the capstan I'd guess pull is not a limit.
I'd had more than 15' of top guy clearance. I think less clearance is
the biggest problem for you unless the tram cable can go higher on a mast.
Grant KZ1W
On 9/14/2019 7:02 AM, Charles Morrison wrote:
Will this work using a TRAM system and not a crane ?
Antenna to raise: 310 lbs x 48ft boom to be installed at 123'
Tower: 132' 55G (130MPH guying) with starguy at 122'
Tram wire: 1/4" EHS
Pulley on tram wire
Tram anchor point: at ground level @ 300ft away from target tower.
Slope: 0.41
Antenna launch point 135 feet away from target tower. (h=0) (165 ft from
Tram anchor point)
Attach 1/2" rope to TRAM WIRE PULLEY - up to pulley @ 130ft - then down to
electric rope capstan.
Begin tightening tram wire to slope thereby raising antenna located 165 ft
from target tower off the ground.
Then begin tramming antenna with electric rope capstan.
What weight/mass do I need at the tram anchor point ?
Tree ?
Vehicle ?
Deadman anchor in ground ?
Antenna launch point can not be moved. Lot is too narrow and theres another
tower nearby.
As an alternative, I may a usable tram anchor point 400+ feet away. - I'm
going out to look ant how that lines up now ....
-Charlie N1RR
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