Am Operation; Other Operations - Icom IC-730 Instruction Manual

reception.
By setting the T/R switch to TRANSM IT, the TRANSMIT
indicator is lit and shows that you are ready for CW trans-
mission. When you key the keyer, the meter needle moves
and your ON signal is transmitted. To increase the trans-
mitting power, turn the RF POWER Control clockwise to
adjust while watching the meter needle on the Po scale for
the desired output power.
5 - 3 - 3 CW SIDE-TONE (MONITOR)
When keying the side-tone oscillator is activated and an
800Hz tone will be heard. The loudness of-the tone is
controlled by the CW MONI Control located under the
access cover. Rotating the control clockwise will increase
the loudness. This tone is also audible in the receive mode
and can be used for code practice, adjustment of the keyer,
etc.
5 - 3 - 4 SEMI BREAK-IN OPERATION
The IC-730 has Semi Break-In CW capability when using
the VOX function. When keying, the unit is automatically set
in the transmit mode. After keying, it is returned to the
receive mode, also automatically, after a given transmit-
release delay time constant. Leave the T/R switch in the
RECEIVE position, and set the VOX switch in the ON (IN)
position.
The transmit release delay time constant is set by adjusting
the VOX DELAY Control located under the access cover.
Turning the VOX DELAY Control clockwise will make the
transmit release time longer. Set for you keying speed.
5 - 4

AM OPERATION

5 - 4 - 1 RECEIVING
Set the operating mode for AM, by switching the MODE
switch "AM". The other controls are the same as those for
SSB reception, except the Pass Band Shift control. The
Pass Band Shift control does not work in this mode.
When tuning an AM signal, tune for maximum signal
strength as indicated on the meter.
5 - 4 - 2 TRANSMITTING
Transmitting AM signals is essentially the same as SSB
transmission.
Set knobs and switches the same as for SSB operation. The
RF output power can be adjustable between 10 Watts and
40 Watts. Also the speech processor can be used on this
mode.
When transmitting the AM signals, the meter (in RF posi-
tion) will indicate the carrier power, and the meter needle
will move slightly according to your voice.
5 - 5

OTHER OPERATIONS

5 - 5 - 1 METER FUNCTIONS
The meter functions as an S-meter in the receive mode,
and as the followings in the transmit mode, according to
combinations of the METER Switch on the front panel, and
SWR switch under the access cover.
RF meter : Indicates the relative output power on the
ALC meter : Indicates the ALC condition.
SWR meter : Indicates the VSWR of the load on the
The combinations of the switch is positions for the meter
functions are as the following chart.
METER
FUNCTION
RF meter
ALC meter
SWR meter
(calibrating)
SWR meter
(measuring)
5 - 5 - 2 VSWR READING
The IC-730 has a built-in VSWR meter for checking an-
tenna matching in order to avoid problems caused by
VSWR. Set the METER Switch to the R F positions, and
the SWR switch to the SWR SET position as the chart of
5 - 5 - 1. Set the operating mode to the AM, and push the
TRANSMIT/RECEIVE Switch to TRANSMIT.
Adjust the SWR SET control located under the access
cover so that the meter needle points to "SET" on the meter
scale. Set the SWR switch to the SWR position. With the
switch in the SWR position, SWR reading can be seen on
the meter. Although this unit is built to handle VSWR of up
to 2:1, it is recommended that the antenna(s) be adjusted
for the lowest possible VSWR. After taking the reading,
return the switch to the SWR SET position. ALSO BE
SURE THAT THE ANTENNA IMPEDANCE IS 50 OHMS
OR THERE MAY NOT BE ANY OUTPUT. OTHERWISE
THERE WILL BE DAMAGE TO THE TRANSCEIVER.
The final transistors used in the IC-730 are of good design
and are protected to a reasonable extent by circuits
incorporated in the set. These devices can be expected to
have an indefinite lifetime since there are no cathodes to
burn out. Under some conditions, however, they can be
abused beyond tolerance and may have to be replaced.
When in doubt about antenna systems, use the Iowest
power setting possible to achieve meaningful readings. Use
caution and exercise judgement when testing RF power
generators.
-- 16 --
Po scale.
SWR scale.
METER SWR
SWITCH SWITCH
RF SWR SET
ALC
RF SWR SET
RF SWR
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