enclosed are 2 photos of a 1A2 card on Ebay. I've never seen a card like this with a piggy-back board attached. seller just shows the MFD as 1977 other then that no info. can anyone ID this card, I've never seen one like this.
This card is a 440A intercom designed to go into a 641A KSU which can be used with the 620 WE key system.
Some key systems such as my 513A2 (http://www.classicrotaryphones.com/forum/index.php?topic=15137.msg157258#msg157258) KSU have two slots for 8" cards.
(http://www.classicrotaryphones.com/forum/index.php?action=dlattach;topic=15137.0;attach=131289;image)
The inductors on this card tell me that it must be one of the Touchtone adapters or TT intercom units, such as the 424B dial intercom. [Ah, yes, 440A TT adapter, thanks]
So, its a 440A? I don't remember seeing it in any KSSM paperwork? is it shown in any practice? what the listing number? I have the WE KSSM vol. 1 and 2 but have never seen it. is it located in another part of the BSP's?
Yes, it is a 440A, the touchtone adapter for the intercom. The BSP is in volume II of the Key Systems Service Manual, and is number 518-215-419.
It can be easily identified from the second photo, when enlarged. It says "440A KTU" on the circuit board edge.