Interconnection Board - Ib - Philips SM40 Instructions For Use Manual

5. SM40 MODULES
5.1

Interconnection Board - IB

Interconnection board for 10 SM40 eurocards. Eurocard pressfit a + b (2 x 32) connectors.
Mounted at the rear of the 19 inch rack frame.
In any sophisticated communication system, convenient and reliable interconnection of the various
Eurocards and other printed circuit cards and components, is vital.
The use of the Interconnection Board (IB) gives the SM40 Public Address Distribution Centre both
reliability and a great deal of flexibility.
One IB is mounted at the rear of each 19 inch frame unit, and contains 10 Eurocard 'Pressfit' connectors of
the 'a+b' (2x32) format, into which 10 SM40 circuit cards can be plugged.
The SM40 circuit card slides along rails within the frame unit and, with a light extra push, is mated securely
with the IB.
Removal of a card is done in the same way; a gentle tug with the special tool supplied, and the card then
slides out of the frame unit for service. After replacing a card always reset the CPC card.
Each connector on the IB is universal, so that the cards may be located in the most convenient order within
the frame. This means that, regardless of the system configuration, every card position in the rack frames
may be used, and that alteration or expansion of the system is both easy and economical.
The power supply and reference signals, common to all of the circuit cards, is carried on rails printed on the
IB, but because the SM40 system has such a wide range of configuration possibilities, a certain amount of
cross-wiring between circuit cards is necessary. This is easily accomplished by terminating the individual
connector wires or flat cables with female Pressfit connectors. These are then pushed onto the pins of the
Eurocard connectors which are exposed on the rear side of the IB.
Interconnection between the IB and the Termination Boards (TB)s is also accomplished using flat cables
fitted with female Pressfit connectors and small individual wiring connectors.
Located between the 10 connectors, on the rear of the IB, are Pressfit (2x8) connector blocks, whose
function is to join certain contacts of adjacent cards together. Small Pressfit jumper plugs are used for this
purpose (making the time consuming use of a soldering iron unnecessary). This 'through connection' of
boards is particularly convenient when connecting an Input Card (IPC) or a Signal Generator Card (SGC)
to 1 or more Matrix Cards (MC)s.
5
5-1