posted 11-11-2009 03:48 PM         

No answers, but a suggestion. Since your DAS has been found to be 'ok' and your having the same problem with a new sensor pad-- Did you try replacing the connecting cable between the two? Possibly a connecting wire in the cable going bad.

posted 11-11-2009 08:47 PM            

I prefer to see a bit of respiration activity in the activity sensor. Nobody is ever sitting perfectly still, and respiratory oscillation in the activity sensor is a nice reminder that the dad-gum thing is working.

Sounds to me like a mechanical/electrical disconnect somewhere in the cable or sensor itself. Have you tried changing the sensor?

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 11-11-2009 09:18 PM            

(pause for prolonged laughter)

Thanks for your suggestions. However, it's not the cable. I've tried 3 cables, including the brand new one that Lafayette sent me with the new pad.

I may need an exorcist.

posted 11-11-2009 09:21 PM         

What does Lafayette have to say about it?

Ted

posted 11-12-2009 12:00 AM            

I haven't talked to them about it lately. In psychology, we call this negative reinforcement.

posted 11-12-2009 02:32 AM         

I'm kinda confused with your discription:
"The seat sensor pad continually loses communication with the software"

... Are you saying the tracing is disappearing while all other tracings are functioning ? or is there some kind of Warning Message Box coming up ?

I sometimes get a Warning Box stating "Cannot find the DAS" for some reason after being in operation (I'm not referring to the loading and start-up of the software)-but will clear when selecting 'retry'---Luckily it has occurred when conducting an actual test.

hmm, an exorcist-- if the price is right I'll come and perform it for you, of course like any other good exorcist- I can't guarantee my work.

posted 11-12-2009 01:56 PM            

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 11-13-2009 10:55 AM            

After reading my post again, I'm pretty sure I won't get a Pulitzer for the writing.

What happens is that the DAS loses contact with the computer. Everything stops. When this happens, the only way to get going again is to restart the computer.

Galling, no?

posted 11-13-2009 02:23 PM         

Yes- from what you now describe, I too have noticed it from time to time. After loading the LX software- and having it running for awhile, suddenly a Warning Box appears and displays 'Can't find DAS' kind of message.

I don't think it has anything to do with the motion sensor pads, or other input sensors. It could be in the cabling- yet like you, when no disturbance (by an examinee) could have affected the cable, it's kinda hard to explain the cable of being at fault.

I suspect, but have really have no idea of, if something is silently running in the background on the computer that is interrupting and causing the DAS disconnect-like a scheduled computer maintenance program or antivirus program- or -power saver mode being used on the computer- that when the program runs silently, it momentarily disconects the DAS.

You should have an three options:"Re-try" (which does not require reloading LX software or a computer reboot- if it finds the DAS again- for me this has generally worked); "Continue without DAS; or "Exit" (which requires reloading the LX software to find DAS- selecting this will may cause you to start a whole new series in-test for the subject).

Sorry- no real answers

Bob

posted 11-13-2009 06:35 PM            

My DAS has a plastic box, so that shouldn't be the source of the problem. So far as it matters, if I run a test without the sensor pad attached, the problem never occurs.

Ray Nelson, who is now a consultant for Lafayette, has emailed me privately and is looking for a solution.

Thanks to everyone for your input.

posted 11-14-2009 06:10 PM            

Laptop or desktop 'puter? Running on battery or AC? If AC, then any power managment or power conditioning. I used to work in an old building with an increased voltage level (>120) that would cook components rather quickly. We had a backup power system that was continually pulling down the voltage to normal levels. Any power-saving or power management tools possibly shutting down your USB. How many USB devices on the port? How many USB ports? Operating system (XP, Vistchuck, or 7)?

I've seen my DAS disconnect from my laptop while running on battery, when the computer attempts to sleep.

You've probably checked all these things, but at least we'll go down the list again.

There is a reason for this. Neither the polygraph nor the computer have any magical or mystical forces behind them.

r

------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)

posted 11-14-2009 10:36 PM            

To avoid the problem, I have to connect my laptop to the DAS then start the computer. I have experienced the loss of connection when my laptop was already running and I then connected to the DAS.

Agree there could be a conflict with another software program.

Would be interested to find out if or how the DAS splits the signal for the different components.

Jim

posted 11-19-2009 07:18 PM            

If ANYONE here defends PC's in the next post, I swear (getting red-faced here)I will personally arrange a drop-shipped, wrecked Baby s. green ford pinto to your house---- and instruct the trucker to park it in your front lawn.

posted 11-20-2009 08:25 AM            

It has never quit in the middle of an exam unless I move my computer or the connecting line. Even that decreased dramatically after the LX4000 was coated.

posted 11-23-2009 11:31 AM            

I run Axciton and periodically, a single pixel line shoots up or down the height of the screen from one of the component tracings. It is random, has no effect on my ability to conduct or evaluate an examination, but it really pisses me off when I address it with Bruce and it's automatically blamed on either the computer (a very expensive Panasonic Tough Book) or Windows (the current and up to date version).

Windows is an operating system designed to provide a platform and underlying libraries to work with literally hundreds of thousands of application software programs. When one of those software programs doesn't play nice, blaming Windows or the PC is like blaming the transportation department for putting curves in the roadway because the vehicle you designed has no steering wheel, or one that only turns in one direction.

Polygraph software/ hardware developers have three simple options. Either you design your stuff so it operates successfully under the Windows operating system; design a complete piece of equipment that has its own motherboard, operating system, hardware and software or blame the other guy's hardware/software for your problems. Option three seems to be the preferable choice by some of our polygraph manufacturers.

We accepted the computerized polygraph running on a desktop/notebook computer when we should have demanded a unique piece of equipment and software designed specifically to conduct polygraph examinations. We could have done our reports on the computer after we finished with the test. I’ve yet to go into a doctor’s office and have an EKG, EEG or MRI done from a notebook computer with a box plugged into the USB port. You either accept what you get in life or ask for what you want. What you get depends primarily on what you are willing to accept or what you demand.

posted 11-24-2009 10:56 AM            

I’ll be the first to admit that we humble techies do occasionally make mistakes and sometimes our software/hardware solutions don’t work out or play nicely with other important applications. i.e. The Windows OS. The software and instrumentation the manufacturers provide have a long list of dependencies and control variables. We hope that everyone can appreciate that it’s not easy to cover all the bases and anticipate everything that can possibly go wrong.

It’s definitely our job to listen to clients and correct problems as they are identified. Limestone Technologies maintains a database of every service call we receive and I assure you that we do look for patterns and reoccurring complaints. Our service engineers make every effort to correct any errors or omissions that are our responsibility. We never blame software/hardware problems on our clients.

Your comparison to other medical technologies is very good. Limestone Technologies fully understands the additional accountability and diligence that must be given to medical products that are scrutinized by the US Food and Drug Administration. Our Polygraph software and instrumentation is not regulated by the FDA however we do manufacturer and distribute medical products that do fall under FDA jurisdiction. The FDA requires meticulous risk analysis documentation for FDA approved instrumentation and software. This translates to a tedious line by line execution of every line of software code in the application. This careful step by step run through ensures that software does exactly what it’s supposed to do every time you use it. A documented Risk Analysis provides a more solid guarantee of a consistent result. Risk analysis is a good practice and I believe that this does significantly help to eliminate inconsistencies and unexplained phenomenon in new software releases.