[Microphones] altec 21B/150A

[Wokoun Peter A PHNS]

Hi all,
  I recently acquired an altec 21B/150A condenser microphone.  I've been
searching for the pin connections but have only found them for the 21C/165A
which has an octal base instead of that special 8-pin cannon connector.
Does anyone have the pin connections for this 21B?  Or on a longshot, a
connector for sale?
  Does the 21B/150A take the same voltages as the 21C/165A?
  Also, how does one get at the tube?  There are 2 small screws at the base
but removing these, the connector is still 'firm'.  Thought I'd ask before
breaking something.

73s, pete KH6GRT