I have several 4000SSIs sitting on the shelf. All of them are in working condition with all the ports working and no damage to the screens. For the price you are looking at I will put togeather a system including reciever compact L1L2 antenna and cable, 12 volt power cable, trimble hard case, a osm battery charger with 110v power and download cable and if you want it a tdc1 data collector. If you want send me an email and I can send some pictures.
Dual-frequency Receiver - Remote Monitor Active
> Friends tell me, "You can do your own brakes, nothing to it, save lots of money." Nope, no way, I'd kill myself.
I haven't done any serious auto repair in probably 20 years, but the first time I did a brake job (mid-'70s, on a 1951 Dodge pickup) I realized just how many ways there are for brakes to fail. It resulted in an immediate change in driving habits, going easy on the brakes. Ever since then I let off the gas pedal and coast up to stop signs and lights instead of zooming up and then jamming on the binders, and in a sudden-braking situation I instinctively look for a bailout heading in the event of brake failure. It was an eye-opener for me.
Dual-frequency Receiver - Remote Monitor Active
Here's what the Saft tech folks told me:
"The LS14250AX is a primary non-rechargeable battery and must not be charged as is listed on its label...Charging the primary LS14250AX or any other primary Li battery will result in potentially dangerous conditions."
That got me concerned, so I pulled one of the original batteries out of the HAZMAT container, and see that it's a lithium battery. A little research indicates that all lithium (as opposed to lithium-ion) batteries are primary (non rechargeable), so I think I'm okay with the ones I installed. I have a message into the UNAVCO folks, and I'm hoping they'll verify my findings.
Jim Frame, post: 78985, member: 10 wrote: Dual-frequency Receiver - Remote Monitor Active
> I'm letting the batteries charge as I type.
Then again, maybe not. The UNAVCO battery replacement instructions states that "rechargeable lithium" batteries are to be used, then lists "LS14250-AX or similar" as the desired battery. I used Saft LS14250AX batteries, and out of curiosity decided a few minutes ago to look at the tech specs for them. They're listed as non rechargeable, using lithium-thionyl chloride chemistry, and are "designed specifically for long-term (3 to 15 years) applications, featuring a few åµA base currents."
It sounds like the right application, but without the recharge capability/necessity. I hope!
friend,
you have any photographs of how to change the internal batteries Trimble 4000?
and how to update firmware?
Thank you for your support
[email protected]
Older Ashtech receiver are plenty good for opus solutions. By today's standards, it's hard to make a 2+ static observation. But it works very well. 30" intervals, a few hours obs, and if you're in a CORS rich environment, it's a chip shot.
BTW. Older Ashtech, like a Z-12, output a raw data file called the 'B' file. You can submit a B-file directly to opus without converting to rinex first.
There are new receivers on the market for $2500 that are better than some of the old receivers mentioned.
The Javad Triumph-2 sells for that and Mark Silver's OPUS receivers sell for at or less than that (depending on which you get). With a new receiver, you have a receiver that is still supported with new firmware and warranty and technical support. I'm not sure what Bob's Hemisphere R320 sells for, but it'd probably be worth a look.
I completely understand buying pre-owned. Some of those old receivers (as well as total stations and data collectors) were built like tanks and last forever. But you might not be saving yourself anything in this case, or at least not enough to justify going to something old that will require cobbling together software (read compatibility), cabling, batteries, firmware, etc.
Landman, post: 42093, member: 951 wrote: I've been using three Promark 3s for several years now, but I'm thinking that if I can find one used dual-frequency receiver that I can do Opus solutions and still use the Promarks for local control. I think I can buy a used Trimble 4800 receiver and antenna for $2500.00. Would this be all I need to submit files to OPUS? Does this sound reasonable?
I would look hard, really hard, at the OPUS receivers offered by Igage. Mark Silver is a top notch guy, and his customer support is awesome. I have two of the OPUS X90 receivers, and they just plain work. Simple to use in the field, and the download tool is very simple to use. The price is right also.
I purchased my two receivers a few years ago. The first one was in December of 2013, and the second one in April of 2014. I sold my two Promark 3 receivers (very, very good receivers), and upgraded to these to incorporate the use of OPUS more into my workflow, and have OPUS solutions for ALL of my GPS occupations. I use them in conjunction with my Topcon Hiper Lite Base/Rover setup.
Does anyone use 3 receivers with static observations anymore? And run networks of point-to-point baselines? And make a network of polygons of dX dY dZ vectors?
Does anyone use post processed phase differential?
Larry Scott, post: 374022, member: 8766 wrote: Does anyone use 3 receivers with static observations anymore? And run networks of point-to-point baselines? And make a network of polygons of dX dY dZ vectors?
Does anyone use post processed phase differential?
Yes, how else would you run control networks?
Used up to 7 receivers at once.
My opinion on this should viewed with suspicion (I won't bother to enumerate my conflicts on the subject of this thread as they should be obvious), but here I go...
I sure think that you may be better off with new equipment. A two-year warranty has to be worth a lot in the calculus of equipment that is used in a professional practice. I just can't see spending $1000 for old equipment when you can get brand new for less than $2,000. That said, a known good receiver for $800 is certainly in my comfort zone.
I am pretty sure (hint) that there will be another trade-in program for ProMark 2, ProMark 3, ProMark 120's at some point in the near future that will be really attractive. There have been several programs through Ashtech/Spectra that were widely utilized in the past. The next trade-in program might be very convincing.
If you are currently using ProMark 2,3,120's in static operation, let me strongly suggest that you consider using a dual frequency receiver as the base. If you currently have a pair of PM3's, this would allow you to collect on three points (a L1/L2 Base + 2 existing L1 Rovers). You can process your base in OPUS to get a good site position (long L1/L2 vectors to CORS) and then process the short L1 only vectors from your two Rovers to the base. Three receivers is not 1.5 times better than 2 receivers. I personally think 3-receivers are probably more like 4 times better than 2-receivers.
I probably am the 'go-to' guy for GNSS Solutions support in North and South America. (I still get four or five support calls per week, and no one ever calls with a job that works.) And I still, in spite of it's shortcomings, personally use GNSS Solutions all the time. (And I have plenty of other alternatives available to me.) Trust me when I say that 'using GNSS Solutions or any other L1 only observation to evaluate vectors of significant length' (let's say 10 KM and greater) is the single largest source of frustration.
It made sense to screw around with long L1 only vectors when L1/L2 receivers were $20,000. But by golly, the street price on L1/L2 is now half of what L1 only receivers used to cost. (I will personally take credit for this trend.) OPUS just solves the entire long baseline problem. It is a good thing.
So, yes three receiver networks are in use, and they are much better than two. No question about it.
M
Larry Scott, post: 374022, member: 8766 wrote: Does anyone use 3 receivers with static observations anymore? And run networks of point-to-point baselines? And make a network of polygons of dX dY dZ vectors?
Does anyone use post processed phase differential?
Absolutely, when I need to do networks, I use more than 2 receivers. When I owned my own firm, I personally owned 4 receivers, and the PLS that I teamed up with on a regular basis also owned 4 receivers. We had a ton of redundancy in our networks. Of those 8 receivers, 5 were L1/L2, and 3 were L1 only.
Now with my current position, I have the availability of 6 L1/L2 units, if I include my own. I have to put a proposal in over the weekend for creating a small network of points for another firm for a large topo. I will be using a Network for that project. I like the VRS systems and all, but sometimes good old fashioned static cannot be beat, in my humble opinion.
Jose MPS, post: 373963, member: 11746 wrote: friend,
you have any photographs of how to change the internal batteries Trimble 4000?
and how to update firmware?
Google it. If I remember correctly there are instructions on the UNAVCO website. I went through this process about two years ago with a 4000SSI. It was trivially easy to do, but because of the copper foil and all the standoff screws and nuts that had to be removed and then put back It was also a bit annoying. Unsoldering, removing, and installing and soldering in soldertab batteries is also easy to do, but not particularly fun. Oh and as I recall the firmware loader had to be run in a virtual machine under Windows XP because it would not run under Windows 7. Overall, well worth the time and annoyance.
Larry Scott, post: 374022, member: 8766 wrote: Does anyone use 3 receivers with static observations anymore? And run networks of point-to-point baselines? And make a network of polygons of dX dY dZ vectors?
Does anyone use post processed phase differential?
Truthfully, no.
It's not a matter of quality though. Post processing has always provided me with excellent results, but I personally have not worked any projects in recent years that would have been improved by using static over RTK. The time required to perform a network survey using static observations just doesn't justify the arguably better results I would get compared to RTK. Having said that, I understand that there are those working projects that RTK would not be feasible due to communication limitations. And of course the adage, smoke 'em if you got 'em would seem to apply. The static system in your office or truck is better than the RTK system at your dealer's shop.
I might even sell you a PAIR of Legacy E's with radios, AND memory activated, on them, (4 megs, and 8 megs) All you would need would be a TDS controller, and you would be RTK.
With memory on the rover, so you can do a Post Processed Observation. And, I paid 20 k for this!
Hm.. 1k and you can have them. Guaranteed not DOA.,
All you'd need would be tripod, and a deep cycle marine battery. Rover pole, and TDS or Carlson controller. You can buy a TDS controller for a few hundred off ebay. I'm pretty sure I'd do this.
N
Larry Scott said:
Does anyone use 3 receivers with static observations anymore? And run networks of point-to-point baselines? And make a network of polygons of dX dY dZ vectors?
Does anyone use post processed phase differential?
Yes to both, 6 Ashtech's, 3 - Z-Max and 3 - Z-Extremes using GNSS Solutions, Invariably yield fine results.