I have some field notes done by James C. Conkright, LS3137 in July, 1984. I want to incorporate these into my StarNet project but have a few questions. I think he may have used the T1 (6") we have in the back store room. I don't know what he used for an EDM.
1. He did not measure HI/HT but he does give the zenith angles. My data is 3D, so do I put .2D above his data? His data is essentially 2D but StarNet can reduce the horizontal angles.
2. On his slope distances, I think he measured them twice, read from bottom to top, for example:
1151.18 (his mean)
1151.19 (face1)
1151.18 (face2)
His average to the backsight (2763.86-F2, 2763.84-F1, 2783.86-M) doesn't quite make sense. 2783.86 works for his horizontal distance (off to the left 2763.83).
Maybe I should just use his horizontal distances and not worry about the zenith angles on the theory he probably knew what he was doing there? He was a good surveyor.
3. He closed the horizon to 3/2/10/11 and HSER (a control point, Calif Dept of Health Services abbreviated, they owned the property).
Reading bottom to top at HSER:
[pre]
To HSER: Close Horizon:
269-33-24 (15) mean 90-26-54 (45) mean
179-06-48 2x 180-53-48 2x
269-33-36 1x 90-27-00 1x
[/pre]
The () comes from reducing (or enlarging) the angles to make them add up to 360.
Should I just use his final answer to HSER in one record (269-33-15) or make a record for the angle to HSER and one for the angle to close the horizon?
It was typical in old notes to go bottom to top but here he overall goes top to bottom except numbers are written bottom to top.
> 1. He did not measure HI/HT but he does give the zenith angles. My data is 3D, so do I put .2D above his data? His data is essentially 2D but StarNet can reduce the horizontal angles.
I think that you would precede his data with ".3R" and put ".3D" at the end of it.
That's it, thanks,
.3R
or
.3REDUCE
for 3D data with no HI/HT.
😀
I filed a Record of Survey about a mile north of you, on Creed Road. The history of ill-fated Solano City is a fascinating read involving major-league fraud and some pretty big names. Remains of some of the major earthworks can still be seen.
I think Conkright died in 1985. He never finished the survey. My involvement started with a small topo for the proposed BOQ (Bachelor Officer Quarters) up against the boundary fence. My boss agreed we should survey the boundary to make sure the new project is on our property (what a concept). So I'm going to finish the boundary survey.
We are on the south side Lambie Road just west of Goose Haven Road. Delta Conservation Camp (inmate fire crews).
The corner to 2/3/10/11 appears to have been set off southeast 27', set by the County Surveyor in 1972. Everything I tied (and Conkright too) fits very well except for this monument, a rebar with aluminum cap. Conkright wrote a note to the CS in 1984 letting them know but it's still off, my position matches Conkright's. This is on Goose Haven 1 mile south of Lambie Road.
Our site is part of an old Nike radar installation that the USACE got from Maude Lambie via Final Order in something like 1959. They built all that Nike stuff then disposed of it 5 years later.
> That's it, thanks,
>
> .3R
>
> or
>
> .3REDUCE
>
> for 3D data with no HI/HT.
>
> 😀
That's something I'll save for future reference. Thanks.
I found your survey...
Did you get the unrecorded surveys from the County Surveyor?
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
And that is without any thoughts of interpolation.
Paul in PA
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
Have you ever used a T1? The 6" reading is an interpolation on the scales.
Other Theodolites Use Actual Scale Readings As Model Number
I have a 20" theodolite I have read to 5" without question.
Paul in PA
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
> Have you ever used a T1? The 6" reading is an interpolation on the scales.
Actually, isn't the T1 a micrometer-reading instrument, the T16 being the scale-realing variant?
> Did you get the unrecorded surveys from the County Surveyor?
I got some from the Surveyor's office, and some from DWR. At one point DWR had a project planned for the area (I don't recall what it was) and did a lot of surveying for appraisal purposes. There are DWR monuments out in the middle of nowhere in that section, and I was very surprised to come upon them.
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
I played with it a little but that was about a year ago, I just remember its least count is 6". Does it have a lower motion? I don't remember. Whatever instrument Conkright used was able to double angles and appears to have read to 6".
We also have an ancient T2 but I couldn't figure it out. My last employer had a bunch of new style T2s, they were fairly simple to operate and I could get really precise splits with them.
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
There are a couple of variants of the T1. Some of them the micrometer is graduated in 20" increments and you might be able to split that by eye or even perhaps quarter it. Others the micrometer is only graduated to the minute and you are expected to interpolate to 0.1 minute by eye.
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
I used a new-style T1 a lot in my early years, and my recollection is that the micrometer reads directly to 6 seconds.
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
Hmmm - don't think I've seen one of those. I'll have to do some checking to possibly update my memory banks.
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
> I used a new-style T1 a lot in my early years, and my recollection is that the micrometer reads directly to 6 seconds.
I'm thinking I've see them direct to 6 seconds and I seem to remember one that had decimal minutes.....
that's drawing back a 30 year old curtain...
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
http://www.mohaveinstrument.com/NewFiles/T1E.htm l">New-style T1 description
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
T16 - 1 minute theodolite.
T1 - 6" theodolite.
T1A - 20" theodolite.
T2 - 1 or 2?
I Don't Get It, A 6 " Theodolite Should Be Read To 2" Or 3"
I tried to post that URL from my phone while at the ballpark and didn't notice that it got corrupted. Let's try that again: