Timer Feature Desiqn Considerations - IBM Series 1 User Manual

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Pigure 3-4 shows the jumpers required on the timer card for
the external signal lines and device addressing.
TIMER FEATURE DESIGN CONSIDERATIONS
W
ir!.!HI Practices
All signals brought into the top-card connector shall be
with twisted pair. The signal ground wires from all sources
associated with a particular timer shall be soldered
together at the connector card and brought into the timer on
pins A05 or
B04
respectively.
The voltage and ground associated
with
the drivers,
receivers, and filter are isolated from the timer voltage
and ground used for the timer card. This isolation is to
decouple external circuitry noise from the digital voltage
and ground for the timer card.
A
single ground strap should be connected from
A08
on
the top-card connector to a suitable frame ground point on
the card file.
ApElication Notes
The cable connecting the user's lines to the timer card
made using a Berg* connector part number 65405-005
equivalent). The pins are Berg part number
75598-003
equivalent) and the recommended wire
is
number 24
twisted pair.
is
(or
(or
AWG
*Berg Electronics, Division of
E.I.
duPont de Nemours, Co.
Timer Feature 3-15