I Swr; D Measuring Swr - Icom IC-703 Instruction Manual

6
FUNCTION FOR TRANSMIT

I SWR

D Measuring SWR

The IC-703 has a built-in circuit for measuring an-
tenna SWR—no external equipment or special ad-
justments are necessary.
The IC-703 can measure SWR in 2 ways:
(A) Spot measurement; or (B) Plot measurement.
(A) Spot measurement
q Confirm that the output power is over 5 W.
w Push [MENU] one or more times to select
e Push [
] to select the SWR meter.
(F-3)
r Push [MODE] one or more times to select CW or
RTTY operation.
• Key down or push [PTT] to transmit; then read the ac-
tual SWR from the meter:
➠ ≤ 1.5 well matched antenna
➠ > 1.5 check antenna or cable connection, etc.
(B) Plot measurement
Plot measurement allows you to measure the SWR
over an entire band.
q Confirm that the output power is over 5 W.
w Push [DISPLAY] once or twice to select .
e Push [MENU] one or more times to select
r Set the center frequency for the SWR to be mea-
sured.
t Push and hold [
(F-1)
lect the desired frequency pitch.
y Push and hold [
(F-2)
the desired step.
u After selecting the desired pitch and step, push
[ ] to measure the SWR.
(F-3)
• RTTY mode is selected automatically.
i Push and hold [PTT] to display the SWR in a bar
graph readout.
o When [PTT] is released, the frequency marker and
frequency indication move to the next frequency to
be measured.
S1 3 5 7
P
O
The antenna is well matched in this range
!0 Repeat steps i and o to measure SWR over the
entire frequency range.
!1 When the measured SWR is less than 1.5, the an-
tenna is well matched.
55
] one or more times to se-
] one or more times to select
RTTY
BLANK
VFO A
9 20 40 60dB
CH
5 10
4.0
3.5
3.0
2.5
2.0
1.5
1.0
[MENU]
.
S1
SWR
SWR
The best match is in this range.
.
[MENU]
Frequency span
Step bar indication
Frequency indication mark
Measure start indicator
Push [F-1] for 1 sec. to change the se-
Span
lected span.
Push [F-2] to change the step bar (3, 5,
Step bar
7 or 9 steps are available.
Marker Indicates the currently active step bar.
Flashes while the SWR is being mea-
Start
sured.
[MODE]
[F-3]
[DISPLAY]
CW
BLANK
3 5 7 9 20 40 60dB VFO A
∞
CH
1 1.5 2 3
∞
1 1.5 2 3
[F-1] [F-3]
[F-2] [DISPLAY]