Seriss 1A2 KSU - Features in REV-J3

[Greg Ercolano]

Here's revision J3 of the Seriss KSU which is the current release:

Fig 1 - Revision J3 board, showing new velcro slots and "L1+L2 BELL" terminal block

What's new is mainly the addition of velcro strap holes, which can be seen in the above between the amphenol
connectors, allowing one to optionally secure the phone connectors with small strips of velcro, similar to the kind
used on 66 blocks:

Fig 2 - Velcro straps securing all 4 amphenol connectors

Fig 3 - Closeup of velcro strap

Velcro has been used for years to retain amphenols on 66 blocks, so with some adjusting to the
trace paths for the line bus, was able to make room for these slots. The board printers (PCBWay)
did a great job making the precision curved holes; very happy with the result:

Fig 4 - Closeup of machined holes for velcro straps on bare board, before amphenol connectors installed.

Also new in this revision is the additon of "L1 + L2" two terminal screws that provides the AC ringing signals for the board's
two lines, so that they can be connected to a SECONDARY board (when two boards are interlinked), or to a 66 block or diode matrix
for special ring configurations.

Fig 5 - New "L1 + L2 BELL" terminal block

For instance to have an incoming call on Line #1 ring all extensions, (something previous versions did not support
due to incoming call ringing being only available on the extensions on the same board as the ringing line), you can
extend a wire between the PRIMARY and SECONDARY boards this way:

Fig 6 - Extra wiring detail for linking the "L1+L2 BELL" terminals for ringing line #1 across all extensions