MFJ MFJ-9218, Инструкция по эксплуатации, Страница: 7 / 10

MFJ-9218
SWR Meter, Wattmeter, & Dummy Load
Instruction & Technical Manual
Z
x
= R
3
V
0
R
2
−
V
BD
(
R
1
+
R
1
)
V
0
R
1
+ V
BD
( R
1
+ R
2
)
. (3)
Now that we know the impedance in terms of known quatities ( R
1
= R
2
= R
3
= 50Ω, V
BD
is
measured by the meter, and V
0
is “programmed in” during SWR calibration), we can determine
the SWR using Equation 4.
SW R ≡
Z
x
Z
0
±
1
(4)
where in our case, Z
0
= 50Ω.
2.3 FEATURES
2.4 CONTROLS & CONNECTIONS
Figure 4: MFJ-9218 Controls. 1.) METER SET, 2.) INPUT, 3.) OUTPUT, 4.)TUNE/BYPASS,
5.) SWR/SET, 6.) Multifuntion Meter
1. METER SET: Adjusts the sensitivity of the multipurpose meter
2. RADIO: Connect to the radio
3. ANTENNA: Connect to the antenna
4. TUNE/BYPASS: Bypasses the MFJ-9218
5. SWR/PWR: Toggles between SWR and wattmeter modes and engages the internal load
6. Multipurpose Meter: Displays SWR and power depending on mode
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