211117/19 hf Mesh anchors on towers
17nov21
19nov21 - measure location on T12 with
bar.
These measurements gave incorrect results. the method assumed
the theodolite as at ao9 (center of the towers). It was
located many feet to the side (since we no longer have access
to ao9 theodolite mount).
See
06dec21 for the corrected measurements.
Anchor hooks have been attached near the top of
the 3 towers for hoisting purpose. They could also be used for
attaching the HF mesh except that the top of tower 8 is about
60 feet below the tops of tower 12 and 4.
On 17nov21 we went to the center of the dish with
the tm50 theodolite. We:
- Place the tm50 close to ao9 so we had a clear shot
of the 3 towers
- after leveling the tm50, point at the bottom of the anchor on
t8.
- Then swing the theodolite in azimuth to point at tower 4 and
tower 8.
- We took low res and high res pictures of each of these
positions.
The table below shows the measured points. Since we are mainly
interested in the zenith angle, the azimuth 0 point was
random.
location
|
az
Deg:D:M:S
|
za
Deg,D:M:S
|
Distance
ft
|
pictures
|
lowRes
|
hiRes
|
T8
|
303.70161
303d42'5.8"
|
53.7070
53d42'25"
|
868.08
|
.jpeg
|
.jpeg
|
T4
|
184.01778
184d01'04"
|
53.6860 (1)
53d41'09"
|
849.00
|
.jpeg |
.jpeg |
T12
|
62.69627
62d41'46"
|
53.7049
53d42'17"P
|
854.18
|
.jpeg |
.jpeg |
Notes:
- The za reference on T8 was the lower edge of the hook that is
in place
- The theodolite was about 8 feet NE of ao9 (the center of the
towers).
- (1): when shooting T4, a horizontal scaffolding
bar was in the way so we decreased the za a bit to be
above it. This is why the za does not match the other 2.
- 1" in za is about .05 Inches at 850Ft.
- 1' in za is about 3 Inches.
processing: x101/survey/211117/doit.pro
211119 - anchor location on T12 using
bar.
On 19nov21 we measured the location of the hf
anchor on T12 using the tm50 and a bar lowered from the step
back.
The procedure was:
- site to the bottom edge of the T8 anchor
- swing in azimuth till we pointed at T12.
- Lower the bar from the platform until it was aligned with the
cross hairs on the tm50.
- mark the location of the bar.
- measure the distance from platform to tower stepback.
the table shows the picture of the bar:
Location
|
az
|
za
|
pictures
|
low res
|
high res
|
T8
|
03d109'32.3"
|
53d53'42"
|
|
|
T12
|
122d21'15"
|
53d53'45"
|
jpeg
|
jpeg
|
- The T12 high res picture shows the red tip of the bar close
to the tm50 cross hair.
- The tm50 cross hair is located at the bottom edge of the
anchor on T8.
- The end of the bar looks to be 1 or 2 " below the
center of the cross
<- page up
home_~phil
