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RF BOX CATEGORIES – Special Devices
VIRTUAL EXCLUSIVITY BOX (VIRTUAL SWITCH)
The Virtual Exclusivity Box (Virtual Switch) is a feature of the uLINK network. The virtual switch acts like a
mechanical interlock – it prevents any SMD from accessing a resource (for example an antenna) if another SMD
is already using a mutually exclusive resource. The virtual switch is an internal N x N matrix.
Since the virtual switch is unique to Station
Master Deluxe, let's look at an situation with
mutually exclusive resources where the Virtual
Exclusivity Box might be used.
Consider a SO2R installation (two radios, two
SMDs) ... among the antennas are a shunt fed
tower for 160m with a multi-band antenna for
20/15/10 meters and an 80 meter yagi mounted
at the top. While both beams can be used
simultaneously, if either radio selects the shunt
feed no other radio should be allowed to use
either of the beams. This critical situation is an
interaction among three separate antenna paths.
The virtual switch (virtual lockout) was developed
to handle these interactions.
In our example we will insert a 3 x 3 virtual switch between the "real" antenna switch and the antennas. On the
Interconnections tab we will connect the three A ports of the preceding "double switch" to the R ports of the
virtual switch and connect the antennas to the A ports of the virtual switch.
Since switch is virtual, it does not need any control outputs. However, to be controlled it must have a (virtual)
Control box associated with the (virtual) RF box. For this purpose we can use a virtual unit of zero (0) outputs on
any uLINK RELAY module as long as the unit is defined on the Control Boxes tab.
Once the unit has been defined, we can set the
InVectors on the Switching tab. Switching and
Break before make delays can be zero because
switch is instantaneous – it has no moving parts.
The Output count is zero because the (virtual)
RF box is not controlled by any physical relays –
only the InVectors.
The Switching table contains three columns –
one for each R port since an R port can only
connect to its associated A port. The InVectors
specify the allowable combinations.
In our case, InVector 100 000 000 means that
when R port 1 (160m) is used, the other A ports
must be off (first 100 part) and the other R ports
may not be used (000 of other two parts). When
R port 1 is not engaged, R ports 2 and 3 can be freely used. This gives three possible combinations: tribander
only (000 010 000), 80m Yagi only (000 000 001) or both by separate radios (000 010 001). All combinations
must be explicitly defined. Masks are not allowed for virtual switches.
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