Two of my three Locus units have displayed somewhat unusual behavior at start up. This has been occurring almost since their first use this fall. Occassionally, after first turning the unit(s) on, they will sit for long periods with only the battery indicator light and a solid red satellite light. In the past, I have turned the unit(s) off and back on and waited 2 or 3 minutes, gave up, and started another unit in it's place. Then after moving the cranky unit to another location, it was up and running with a full load of SV's within 30 seconds. In every case after setting a second unit in place of the cranky unit, the second unit performed normally.
This past week though, I gave up on one unit after trying for 5 minutes to lock a single SV, set up a second unit and was up and running. Drove a couple of miles out to set up second and hopefully third units. The second unit was set up and got a lock on 7 SV's within 30 seconds. The "cranky" unit was set up some 300 feet from the second unit. It took 15 minutes before logging any data. The processed data (after 1-1/2 hr, less 15 minute, session) was great.
My question is, why the long lag times on certain units when another locks almost immediately? Do I have hardware problems already?

Thanks

J.D. Billings

J.D.

I had the same thing happen a few months ago. Of course it was the last session of the day.
Gave up on the session and brought it in, downloaded what I had and then took the receiver ack outside and tried again. same thing. Red constant battery light and no receiving sats. I then performed the full reset. It has worked fine since.
Memory allocation wasn't an issue, this has happened to me only once in the past 14 months and I consider it the usual very uncommon glitch similar to an hp 48 with TDS that on occasion has a bad day.

er, that was supposed to be continuous red sat. light, not the battery.

Dave,

Thanks for the reply. I can also sympathize with you on the 48/tds. Over the years, I've lost a couple of days data myself. No fun, but at least the rodman knows where he's going and what he's giving shots on the next day.

J.D.

P.S. I know I did a full system reset on one receiver a couple of weeks ago when I installed fresh batteries in all the receivers, for just that reason. I intended to do all the receivers but had a session underway and forgot. I'll do the reset again on all three and see if it corrects the problem. I wonder though, will the full system reset affect the battery life timer? In my case it won't really matter since I only have about 5 or 6 hours on the new batteries anyway.

J.D.,

Let me know if you are still seeing the same behavior after you reset the receivers. What you are seeing is not normal behavior.

Bill Martin
Ashtech Precision Products

Bill,

Thanks. I did a full system reset on all three units this afternoon and let them run about 45 minutes on the toolbox of the truck. We will probably find out tomorrow or the next day how it works. This happened a couple of times with one receiver, when a second receiver in it's place seemed to work. The mysterious antennae test range we worked on for several weeks was the first we noticed a problem. The next week, on a totally different project, all receivers worked normally. As I stated above, I did a system reset on the questionable receiver after changing batteries in all receivers. We were on the "antennae test site", of all places, when this receiver again decided not to lock. After the reset, it slowly locked on 5 SV's in about 15 minutes. Worked fine ever since. Now a second unit is lagging. I guess it's not the "antennae test site" radio interference deal after all.
Will let you know after a good test.

Thanks

J.D.

I have a 3 reciever locus system for approxmately 8 months. One of my recievers had this same problem within 2 months. I first did a hard reset and It works for several weeks but the problem return. I sent the unit to Lietz for service when they returned it they found no problem of course. I continued to have intermitent problem. I even tried additional hard resets!
Finally, I persauded supplier to swap out that unit for me.

Used my Locus receivers today, one of them was slower than the other to get going in similar very open conditions. The first one started like usual on a cold start, was logging 8 sats very quick. The other started with the solid red sat light for about a minute, then picked up 2, then 3 and so on. Strange. Download of data looks fine. So I'm happy.
I wonder if we could isolate the "seem to be slower than the other" units by serial number and relate it to the build date. My slowpoke of the day is SN LC 120001711. How about you J.D.?

Dave,

The two receivers I've had problems with are LK119993362 and LK119993332. I think I see where you're coming from on the serial numbers, but I don't see a relation between your numbers and mine. I did do a hard reset on all three units the other night. Left them running about an hour and a half in the yard, spaced some 5 feet apart. Got a bit cockey and decided to do a repeat vector session. Cranked them back up for another hour and a half. Unbelievable adjusted results. No failed vectors, repeat vectors passed, chi square passed, etc. Wish I could get those results on those short 300-1000 foot lines. I'm sure, since this was well after sundown, ionosphere was quiet, aiding the process.
A full field session yesterday and all three units performed perfectly. I really doubt that it will last though.

J.D.

The unit SN in had trouble with was
LK119993321.