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INSTRUCTION MANUAL
ARI-6000-100W
RF Power Amplifier
SECTI ON 5
-
OPERATION
1912 1 E l T o ro R d
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Si l vera do, Ca lifo rni a 9 26 76
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(9 49) 459 -96 00
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co m-p o wer. com
REV011718
5.1.8.1 Example: Setting the VSWR Monitor
This item is used to select the difference between the forward
and reverse power levels (loosely defined herein as VSWR;
however, the literal term for this parameter is ‘RETURN LOSS’)
that will result in the amplifier automatically setting the gain to
zero, then ramping back up toward the previous gain or ALC
setting. If the fault condition persists, the output power will
continue to cycle until the condition is rectified.
Example:
In this example, the “Max VSWR” setting is changed from 2.0 dB
to 5.0 dB.
User:
Select “VSWR” from the main System Configuration
menu.
Unit:
Top line displays: “Using the 'UP' and 'DOWN' buttons, set
the minimum value for the VSWR alarm, and press the
MODE button.”
Second line displays: “Max VSWR: 2.0 dB”
User:
Use the
↑
and
↓
buttons to change the VSWR Alarm level
until it reads “Max VSWR: 5.0 dB”, then press the MODE
button.
Unit:
Stores the information and returns to the main System
Configuration menu.
NOTE:
A “Max VSWR” setting of
2 dB
on the amplifier
actually represents 2 dB
Return Loss
, which correlates
to a VSWR of approximately
8.7:1
. With this setting,
the fault indicator light will turn on if the return loss is
less than or equal to
2 dB; which corresponds to the
VSWR being equal to or greater than 8.7:1.
A “Max VSWR” setting of
5 dB
on the amplifier
actually represents 5 dB
Return Loss
, which correlates
to a VSWR of approximately
3.6:1.
With this setting,
the fault indicator light will turn on if the return loss is
less than or equal to 5 dB; which corresponds to the
VSWR being
equal to or greater than
3.6:1.
See Table 5 for a complete cross-reference of Max
VSWR Settings [Return Loss values] vs the respective
VSWR values.
The relationship between VSWR and Return Loss is as
follows:
VSWR = 1 +
ρ
1 -
ρ
= Power(10,([
Return Loss
]/20))
ρ
= Reflection Coefficient
