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SENSOR 1 MENU – ANTENNA CABLES
In previous chapters we have several times used and described term “two point measurements”, so you should
be already familiar what does mean ANT feed point. To calculate power at the ANT feed point, SMΩRF needs to
know what kind of cable is used to connect antenna and its physical length.
This purpose serves ANTENNA CABLES menu which allows to set cable model connecting particular antenna
as well as set its length. Additionally, it allows to set meaningful cable name according to the name of the
antenna (every cable ends up at some antenna) and assign antenna to bands where is used.
SMΩRF has allocated memory for up to 32 different antenna cables per sensor, each cable is identified by its
unique ID number. There are more than thirty (30) built in, precise models of common coaxial cables types to
choose from.
There is one special cable called Lossless 50Ω, which is used as default. It is a virtual cable which just specifies
reference impedance for the ANT feed point calculations and since it has no loss, entered length is irrelevant.
Results using this cable will be same as measured values at the TX feed point. Use this cable if your cable is not
available or you have no idea what cable or length you are using to avoid reading incorrect and misleading
results for the ANT feed point.
CONTROLS:
1. ID
Selects Antenna Cable identification number.
2. NAME
Sets NAME of the Antenna or Antenna Cable.
3.
L
Sets physical length of the cable in meters or feet.
Units are set in SYSTEM MENU | MISCELLANEOUS.
4.
CABLE TYPE
Defines coaxial cable type.
5.
BAND ASSIGNMENT
Assigns cable to one or more bands.
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