Diagnosing diagnostic problems.

Dear Editor,

Trying to diagnose Sentinel problems with faulty diagnostic equipment is about as bad as trying to operate at night with Faulty night vision goggles. These two tips can save you hours of troubleshooting:

* Test all the diagnostic spares regularly, especially before deployment and field exercises. The Sentinel has 31 spare parts, such as circuit; cards and power supplies, so this is no snap job. Plug the part one-by-one into a known good system to make sure they all work. This is a good exercise For Sergeants' Time.

Otherwise, you could be trying to fix a system by installing defective parts and what might; be a small problem seems to be a much bigger one.

* When troubleshooting don't remove any diagnostic spares you've installed until the problem is totally fixed. Then once the Sentinel is Fixed, begin putting in the original parts, starting with the first spare parts installed. Sometimes more than one part has been Fried or is defective. This way you can easily see which parts were bad.

SGT David Gilmore 1-44 Air and Missile Defense Battalion Ft Bliss, TX

Editor's note: Nice diagnosis, Sergeant. I think your suggestions will produce a good prognosis for Sentinels. Always remember to wear ESD protection when handling circuit cards.