Stratus For Control

Used L1 static GPS for control for years. I had a set of Locus then a set of Stratus. The stratus will work fine for control points, and you don't need any kind of controller. They are one-button operation so you just turn them on to collect, turn them off to move to the next point. IIRC, they have a "timer" that lets you know when you are good for 5km, 10km, 15km or 20km. I think 20km takes about an hour, and is pushing the limits or L1 GPS. The post processing software was called "Spectrum", and I'm not sure where you get it. There might be a free L1 only version on the net somewhere.

Keep in mind with L1, unless you have a CORS nearby, you'll probably have to tie in an NGS monument to get SPC. You won't be able to Run OPUS.

I have three plus the controller.
Latter sits at home. It is useful as it sets up the height of the unit, but that is easily added in the software during process.
Personally I believe three simultaneous observations are preferred over two.
I do move mine around at times, but one is static full time, others rotated but try for overlapping times.
I set them up at start of day and take them down at end, often get 10 hours obs, common for 6-8 hours.
Generally they sit on top of a non tilting target set.
They run on the smell of an oily rag. Just watch the battery level and don't try and download if batteries are low in case data is lost.

The battery doors are the weakest part of the device so take care with them. They are expensive to the tune of $100± so I am told. I broke one!!
Now has a wide rubber band to keep it shut.

You can download with a USB to Comms (DB9) converter and works well on my Win 7 Pro 64 bit laptop.

I wouldn't be without mine.
Have a couple of Locus, but haven't used them for ages.

Spectrum Survey available for free for L1 processing. Not sure where, try POB Forum and look in the Sokkia section. You will have to login for that.

Stratus For Control, Go For It

Several suggestions, get fixed height rods and SECO three legged bipods for several positive reasons.

First/ Fixed height means never having to change antenna height again.

Two/ I have two piece rods, and I can break them down, leaving my ProMark 2s and antennas on the upper part. I leave the bipods attached to the lower part, just below the reinforced top connection. I moved the bubble down and it peaks out the side. It cannot come out the front because of the three leg orientation. Break down and setup goes fast.

Three/ Much lighter than tripods.

Four/ Uniformity of parts. I have 4 Crain rods, 2 Alumalites and 2 Composolites. They are the same length and bottoms and tops of any setup may not be the same material.

I started with 2 ProMark 2s and quickly added a third, they came with the rods and bipods. When I got a 4th receiver (not a PM2) I bought another Crain rod and a cheap 3 legged bipod. By leaving the 3 legged bipod on the lower section the bipod points extend out farther than the rod point, making it inconvenient when setting up. I quickly fixed that but using the 3" extender that comes with ProMark 2s between the rod bottom and the rod point. Since it is a smaller diameter than the rod it keeps the bipod leg foot washer from hitting the rod and it packs tighter. Since I only had 3 ProMark 2s I matched the 3" on the 4th rod by buying 5/8" extender nuts (1 1/2" each) at the auto parts store and using a 4" piece of 5/8" all thread.

On my first really big control job I used my 3 PM2s and borrowed 2 more. After a day I found that with 5 receivers I could not keep up. Overlap occupations were much longer than necessary until I got around to moving a unit. I found I could be just as productive using 4 receivers. Break down and move 1 setup. Go to next setup and wait for the minimum time to the most recent setup, then breakdown and move again.

If you have a lot of work, consider a 4th receiver, a Locus, PM2, PM3 or Stratus, i.e. something simple. Another alternative is a an old slow L1/L2 receiver, which can be had pretty cheap these days. I have Ashtech Z-12s.

Assuming you stay L1 only consider getting GNSS Solutions or some other software that allows for a static VRS. When I do a VRS L1 project, when I download my receivers Solutions goes on line, finds 3 nearby CORS, downloads data and creates a Virtual reference station within my project that allows for short L1 vectors from the virtual L1/L2 control point.

Paul in PA

Stratus For Control, Go For It

GNSS Solutions looks like it should work but I'm having problems fixing base lines. Just started to use this software was hoping to solve a position the same day as I could download rinex data 1 hour later, using a X90 OPUS is there any other software I should look into and what's the cost?

Stratus For Control, Go For It

> GNSS Solutions looks like it should work but I'm having problems fixing base lines. Just started to use this software was hoping to solve a position the same day as I could download rinex data 1 hour later, using a X90 OPUS is there any other software I should look into and what's the cost?

The X90 OPUS is L1/L2. The stock version of GNSS Solutions is L1 only, so to post-process with that package, you'll need to keep baselines under 20km and have about an hour of static data for those long baselines. It's the L2 component that lets you have very long baseline and shorter observations. When processing against CORS, you often end up with very long baselines, which is not suitable for L1 processing.

You can buy an upgrade for GNSS Solutions that activates L2. I think it's $995 last time I checked.