By far the msot common is the getter. Why is it usually on top? Because
that's where the original metallic barium or other highly reactive material
was placed during manufacture. Sometimes it's on the side or near the
base. But since it's a metal and conductive, has to be placed away from
an area where it could short between pins.
--- sam | Sci.Electronics.Repair FAQ:
http://www.repairfaq.org/
Repair | Main Table of Contents:
http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ:
http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites:
http://www.repairfaq.org/REPAIR/F_mirror.html
Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.