Rohde & Schwarz OSP-B200S2, User Manual

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Modules
R&S
®
OSP
119 User Manual 1178.7100.02 ─ 05
3.43 R&S OSP-B125 RF Switch Module
Figure 3-99: R&S OSP-B125
The three-slot (triple-width) module R&S OSP-B125 (order no. 1515.5540.02) consists
of 6 failsafe SPDT relays and 3 failsafe (open) SP6T relays, all electromechanical. The
frequency range is DC to 18 GHz, with internally terminated SMA (female) connectors.
The module requires 2 module bus cables.
Note: Mind the torque limit recommendation of 56 N
·
cm for SMA connectors.
SPDT relays:
The relays operate independently from each other. The terminal port is labeled with C
(common), the other relay ports are labeled with NC (normally closed) and NO (nor-
mally open). Terminal C is connected either with relay port NC or NO.
The type of relays is monostable (or "failsafe"), hence, with no voltage applied, an RF
connection is provided from C to NC, while NO is not connected to C ("Pos = 0"). To
disconnect NC and connect C to NO ("Pos = 1"), a continuous voltage must be applied
to the relay.
The relays are mounted directly into the module's panel and soldered to the module's
printed board, to avoid relay cabling and allow a compact module size.
SP6T relays:
The relays operate independently from each other. The terminal port is labeled with C
(common), the other relay ports are labeled with numbers.
The relay type is monostable (or "failsafe open"). Hence, with no voltage applied to a
relay, no RF connection is provided from terminal C to any of the numbered ports. To
establish an RF connection between C and one of the numbered ports, a continuous
voltage must be applied to the corresponding power terminal of the relay.
The relays are mounted directly into the module's panel and soldered to the module's
printed board, to avoid relay cabling and allow a compact module size.
The module's on-board memory stores its configuration data.
The switch unit provides power supply and control via two module bus cables to two
module bus connectors on the module's printed board. The available module bus con-
nectors ("Mxx") are shown in
Figure 2-26 .
To find out, which two module bus cables on the switch unit's motherboard your mod-
ule uses, refer to the headline of the control screen as in
Figure 3-101 and Fig-
ure 3-102 . In this example, module R&S OSP-B125 uses buses "M01" and "M02".
R&S OSP-B125 RF Switch Module