Acom 700S User Manual page 36

d) Test transmission with the amplifier
If not readily set by CAT, switch the amplifier to the same band as the transceiver and antenna (see Section
3.5.1) The OPR/STB and the BAND buttons
Set the transceiver to a continuous carrier mode and minimum power. In OPERATE mode choose a free
frequency and push the PTT or CW key briefly, while watching the amplifier's behavior:
RX mode must change to TX;
•
The reflected power must read below 20 W;
•
The forward power must read between 20 and 150 W with minimum drive power from the
•
transceiver (between 1 and 5 W).
If the above test goes normally, push briefly the PTT once again, this time watching the transceiver's SWR
reading (i.e., the input SWR of the amplifier) - this must be below 1.2.
If the SWR to the transceiver is higher than 1.2, check the coaxial cable between transceiver's output and
amplifier's input socket (see Section
e) Setting of drive level and typical operation
After successfully passing of the above tests push PTT or CW key for several seconds, watching the forward
and reflected power. Increase the drive power until the forward power bar graph and digital readout reach
700 W.
Upon reaching 700 W forward power check the following parameters (continuous carrier operation):
The reflected power must not exceed ~ 78 W (for SWR 2:1) or better still to be below 28 W
•
(for SWR 1.5:1);
PA DC CURRENT must be between 23 and 30 A; it is normal that the current varies within
•
these limits when changing operating frequency and antenna impedance;
PA DC VOLTAGE must be within 42-44 V;
•
The transceiver's SWR reading must be below 1.2:1.
•
Enter the MEASURE menu (see
Тhe drive power from the transceiver must be between 22 W and 29 W;
•
PA BIAS, which must be between 2.4 and 2.8 V;
•
PA TEMPERATURE, which must be between the ambient and 95
•
power level and the duration of transmission.
f) Elimination of electromagnetic compatibility (EMC) problems
If you use an amplifier for the first time in your shack, you may need to make some improvements in the
setup. It is possible you might experience tingling from metallic objects due to the stronger radiated RF
field. It could affect the operation of your station or systems outside, if they are too sensitive - typical
examples are the microphone, CW keyer, computer keyboard or mouse, as well as TV receivers, Hi-Fi,
intercom or telephone setups and others.
Page 36 of 92 | S e c t i o n FIRST POWER-ON, CONTROL SYSTEM, AND INITIAL CHECK
).
2.4.d) RF INPUT connector
Figure 5-2 | Menu AMP MEASURE
User's Manual | ACOM 700S | 1.8-54 MHz Linear Amplifier
).
) and check:
o
C (203
o
F), depending on the
April 2024