Acom 700S User Manual page 35

User's Manual | ACOM 700S | 1.8-54 MHz Linear Amplifier
Now in RECEIVE mode select a frequency which is not occupied at the moment and press shortly the PTT or
TX key while watching the output power and the SWR readings. If the power or SWR at the transceiver
output are too high (over 5 W or SWR over 2:1) release the key and check for the reason as follows:
Check again whether the power control is set at minimum;
•
Check whether the frequency is within the operating range of the selected antenna;
•
Check the good working order of the coaxial cables, connectors, and feed lines from the
•
transceiver antenna connector through the amplifier, the antenna switch or external tuner (if
there is one) to the BALUN transformer, and the antenna itself (see Section
).
connector
If the power and SWR are as expected, transmit again and while watching the power and the SWR readings,
increase transceiver power gradually from minimum to maximum (but not more than 200 W in order to not
overload the RF by-pass circuit in the amplifier).
If SWR remains below 2:1 (preferably below 1.5:1) at the last test, decrease the power from the transceiver
to minimum again and continue with the next check-up.
b) Check-up in STANDBY mode
Turn the amplifier on, as described in Sections
,
Panel 3.3 Initial Turning On
Make sure that the amplifier is in STANDBY mode. Push the OPR/STB button if needed to change to STB.
Repeat receive and transmit tests the same way you just did with the amplifier turned off. During these
tests note also whether the forward and reflected power bar graph and digital readout (see Sections
Forward power bar graph and digital
respective RF power presence. If the reflected power exceeds the forward power, verify that the input and
output coaxial cables to the amplifier are not interchanged (see Section
).
RF OUTPUT connector
The power indication accuracy is optimized around the 700 W level and usually it is
unreliable below 40 W.
c) Entering OPERATE mode
At OPERATE mode the transceiver receiving should not suffer. If it worsens and together with this the
indicator RX changes into TX although the transceiver is in receive mode, check the control cable connected
to the KEY IN input (see Section
transceiver could cause the same problem.
April 2024
3.1 Low Energy STANDBY Mode of the Power Supply
and (see
3.4 Basic Screen
readout and
3.4.f) Reflected power bar graph and
2.4.b) KEY IN connector
S e c t i o n FIRST POWER-ON, CONTROL SYSTEM, AND INITIAL CHECK | Page 35 of 92
).
Figure 3-2 | Basic screen
2.4.d) RF INPUT connector
) for a short circuit. A wrong connection to the
2.4.e) RF OUTPUT
,
3.2 Front
3.4.e)
digital readout) show
and
2.4.e)