OK, I'm at a point I need to know when EDMs first entered the market, and when they came into general practice.
I have a description from 1974, and it's pretty darn accurate, with bearings in DMS to boot. I'd guess a T2 and ? for EDM? Is that a reasonable date?
Can some of you guys help out?
Thanks.
The City of Los Angeles bought dozens of Hewlett-Packard 3800's right after the February 9, 1971 Sylmar earthquake to assess ground movement.?ÿ The theodolite on every crew was a Wild T-16.?ÿ (The City had always owned a Geodimeter and Wild T-2's and T-3's, but the average surveyor probably didn't have them.)
I would say the H-P's had to be available to the public before 1971 as a reasonable-cost distance measurement device.
Rented one in 1979 but the distance measurement device attached to the top of the theodolite. A few years later before we had a total station. ?ÿBut, we were out in the boondocks only doing survey work a few times per month.
I was using a Wild with a distomatD## around 1978
Do not be surprised with your finding ancient surveys that are as accurate as you measure with modern equipment.
Some of the original surveys we follow were made by true surveying masters.
The U.S. Coast & Geodetic Survey, now the National Geodetic Survey began using EDMs in the mid-1950s.?ÿ The first were the Geodimeter Model 2 from Sweden and the Tellurometer MRA1 from South Africa.?ÿ I think the first unit that was really practical for land surveyors is probably the H-P 3800 which hit the market in late 1969 if my memory serves - an increasingly rare thing these days.?ÿ I first used EDM - the Microchain MC8 in 1967 as an Army surveyor.
The first EDM I used was the AGA Model 76 in 1973.
The first civilian job I had was with a 4 crew Engineering firm in 1984. They had one beetle EDM that floated as needed (when it wasn't in the shop). We chained almost everything and did tight work.
The company that I?ÿworked for in 1969-1974 (winters between USFS summer jobs) bought an HP-3800A in about 1970. They had a pair of?ÿCubic Electrotape DM-20(s) for years before that, but?ÿthey were only used on Control Surveys. In fact, The USFS had set of DM-20(s) in 1968, one of which I packed up to the top of Murdock Mountain in the fall of 1969 (arrrgh). The last time I used a set of DM-20(s) was in 1983 to measure from Porcupine Mountain (Utah), to Session's Mountain (Wyoming), a distance of 206,000 feet (more or less).?ÿ
Loyal?ÿ
Edit...NO, that is NOT me in the picture, I was NEVER that clean cut!
In June 1972, I was the proud purchaser of a Wild T2/Wild Di-10 Distomat (approx. $11,000) from Florida Level & Transit, along with the 9 glass prism setup. Partner and I had an office in Clermont, Florida, and ran many miles of section lines across the (former, before they were all killed in in the freeze of the early 1980's)?ÿ giant orange groves of hilly Lake County. Had a series of dials that had to be turned to start the measuring process. Excellent accuracy.?ÿ
The first EDM I used was the AGA Model 76 in 1973.
I still have an AGA Model 76 out in the garage (and a Model 78 in the truck). Not sure either one works anymore, it's been a LONG time since I fired either one up (or even tried to).
Loyal
Geodimeter Model 2 used by some large surveying firms in the 1950's, cost around $25,000.
In around 1958 the Model 4 Geodimeter was used by private surveyors along with
MRA 1 Tellurometer.
The first EDM I used was in 1963 (2 years after joining the U.S. Marine Corps) and it was the MRA 1 Tellurometer
and ending up with the MRA 3 Tellurometer in 1968 2 years before I got out of the Corps.
?ÿ
JOHN NOLTON
When I was employed by the USBR in 1960-1966, we performed a control survey for a proposed?ÿirrigation project in the vicinity of Glendo Reservoir in 1963 using the old Tellurometer, pre MR3, where you had to attach the dish and diode on the face and a rubber tube over the measurement readout so you could see the scope in order to read the trailing edge of the?ÿgreen line.
In 1969 I went to work for the firm that I eventually bought into and then bought complete ownership in. They had two Tellurometer MR3's we used on any major project, route surveys, boundaries or anything that needed a long line measured. Had these until about 2 years ago and sold them to John Nolton. The last time I used them was in 1975?ÿto measure ?ÿa?ÿ7?« mile distance. Started using HP 3800's in 1973, 3805's in 1974 and 3810A's in 1975 until I closed the business in 1987. I had the 3800's and 3805's set up with the verticle circle mount so we could measure independent of exchanging with a theodolite for distance correction.
John also bought my 3800 when he got the Tellurometers.
They say that the HP 3800 put the surveyor in the EDM World.
I began apprenticing in late 1979 working for a guy who had a top-mounted Lietz "Big Red" EDM which he believed (correctly, I think) was the only one in use?ÿ in our part of central Maine at the time. We used it for the big jobs and did in-town house lots and such with transit and steel tape. All data from both systems was recorded by hand in field books.
I had the little Topcon EDM (DM-C) mounted on a T2, and a long range HP that would locate a prism array up to 6 miles. The little EDM would shoot up to 12,000' as I remember. This was 78-79, by the early 80's they gave way to a total stations. The T2/distance meters became control units.?ÿ
The other day I retraced a deed from 1919.?ÿ It showed distances in rods, (like 27 11/37 rods).?ÿ It closed on itself like a glove.?ÿ So they were capable of precise measurement even before EDM.?ÿ I started in 1977 and we did everything with transit and chain, didn't see an edm until 1982 (HP-3800).
Not to be confused with the NGS ??Big Red? described and pictured here:?ÿ https://celebrating200years.noaa.gov/distance_tools/bigred.html
Two websites that might help:
http://www.hp.com/hpinfo/abouthp/histnfacts/publications/measure/
http://americanhistory.si.edu/collections/search/object/nmah_748833
?ÿ
In 1974, my everyday instrument was the Wild T1-A and the HP 3800.
One correction for my post above. The last Tellurometer I used in the military was the MRA 301 not MRA3.
Another note about "GeeOddMike" post ?ÿjust above is under the caption for NGS Big Red, Larry Wakefield NEVER
measured the line of 150 km. This was told to me by my good friend Charlie Glover who had talked to Larry about this.
The measurement was going to be between station "Kitts (PID CG1127)" and station "Why (PID DA1499)" which is only
about 112,430 m (slant distance +/-).
?ÿ
