|
Author
|
Topic: LX4000 Calibration Check Procedure
|
Joey55
Member
|
posted 05-07-2007 01:24 PM
 
Please forgive me if this question has already been asked.I'd like to know how you as LX4000 users do the quality calibration checks. How often do you do them and do you use the resistor box that Lafayette sells for the GSR check? I am aware that Lafayette suggests using a coffee can and the back of the chair but is that what you actually use for your checks? Also, if you have two or three examiners, would it be permissible for both to do the check at the same time and both put the chart printout in their file or should each examiner do separate checks? Thanks very much in advance! IP: Logged |
Taylor
Member
|
posted 05-07-2007 04:19 PM
I have the LX 4000 and the calibration tool. In Utah we are required to calibrate 2 times a year (more if problems begin). I have incorporated calibration into the Utah Polygraph Associations quarterly meetings - so any member can use my calibration tool.As for the 3rd para....I am a bit confused. Do the 2 or 3 examiners use the same instrument? If so, I would think only one calibration test is needed. NOTE: some states require the instrument be calibrated before all evidentiary exams. Taylor IP: Logged |
rnelson
Member
|
posted 05-07-2007 07:52 PM
OK, I gotta ask...Coffee can? Back of chair? Someone wanna 'splain this??? I'm tempted to suggest calibrating a subject using the good 'ole paper-clip and light socket (bzzt). I spent most of the night at high altitude in a heavy spring snow - so I'm punchy right now, and I'm sure I'll regret this post later. r ------------------
"Gentlemen, you can't fight in here. This is the war room."
--(Stanley Kubrick/Peter Sellers - Dr. Strangelove, 1964)
IP: Logged |
Taylor
Member
|
posted 05-07-2007 08:00 PM
You may regret it later - but I got a chuckle out of it! TaylorIP: Logged |
Barry C
Member
|
posted 05-07-2007 08:08 PM
Yes, Ray, it's for real. Technically, it's not a calibration, but a functionality check. In other words, you're (essentially) making sure there are no leaks. (You wrap the cardio cuff around a can with no give.)IP: Logged |
stat
Member
|
posted 05-07-2007 09:51 PM
I've always monitored an X to the XX mil of merc pressure on screen to see if a cardio cuff gets tossed. If I see a loss of more than 3 mils over a course of a 4-5 minute chart, I check the tubes for leaks under water. If the leak is in the cuff, I replace it with a new one and use the old one as a coozie for cans of yoohoo at the park.IP: Logged |
stat
Member
|
posted 05-08-2007 07:36 AM
oops. I remembered this morning that Lafayette uses a spyg dial versus onscreen indicator (I use Stoelting). [This message has been edited by stat (edited 05-08-2007).] IP: Logged |
Joey55
Member
|
posted 05-08-2007 08:51 AM
Yes, the coffee can and back of the chair were direct from Lafayette. I won't say what they said about the GSR, I couldn't believe it! But the price of thier (basically a resister) is a whopping $315.00.About the same operators testing the instrument at the same time, I did mean that it was the same instrument and all operators used the same also. Thanks IP: Logged |
J.B. McCloughan
Administrator
|
posted 05-08-2007 09:12 AM
The price on the part mass-produced would most likely be considerably less expensive. When specialized parts are produced in small quantities, it reflects in the price of those parts. You can expect considerably higher costs due to production costs being figured into a lower quantity of parts. This is not like a big name auto industry who charges hundreds of dollars for a part that they mass-produce at pennies on the dollar. The polygraph instrument manufactures are producing a product for a relatively small-specialized industry.
IP: Logged |
Joey55
Member
|
posted 05-09-2007 09:32 AM
JB, yes I understand the pricing on that part being what it is, but basically the answer I was looking for is how you 'pros' on this site handle the functionality check in case you end up in court. I believe APA in non-court cases refers to the manufacturers recommendations, but is that the way most of you actually do it?
Thanks very much.IP: Logged |
J.B. McCloughan
Administrator
|
posted 05-09-2007 10:00 PM
I follow the manufacture's recommendations for functionality check. It is usually quite apparent to me when a component is not functioning properly. On those occasions, I test the suspected component and, if confirmed, I take the instrument out of service until repaired.IP: Logged |
Polygraph Place Bulletin Board
