RF Power HVLA1K3 PLUS User Manual page 11

7 CONNECTION AND OPERATION with ICOM™ transceiver
This section explains a one-antenna connected to an ICOM™ transceiver provided of "Band
Voltage Output" pin.
7.1 Connect AC power cord and coax cables as mentioned on page 9. Run a shielded control
cable (see page nr.13) from the remote terminals (transceiver producers give different names to
this output; please, check your transceiver's manual) to the amplifier rear panel "AUTO B" D-SUB
(9 pin) male connector.
7.2 Use a short 50 ohms coaxial cable, type RG58 or equivalent for the connection from the RF
output of the transceiver to the amplifier rear panel "RF IN" SO-239 connector.
7.3 Keeping the main power switch OFF, check the VSWR of your antenna by keeping the
transceiver to TX mode (CW, FM or RTTY mode). Monitor the VSWR with an external SWR/power
meter. If VSWR is high, the antenna has to be adjusted for lower VSWR. As an alternative, an
antenna tuner may be inserted.
7.4 Turn the main power switch ON. Turn the "BAND" rotary switch to "AUTO B" position (green
LED "AUTO B" will light). Turn the "ANTENNA" rotary switch to a specific antenna, if necessary.
Turn the "STBY-OUT" rotary switch to the low output power position of the amplifier (green LED
"LOW" will light). Now, key the transceiver with the carrier level set relatively low (such as 10
watts) and monitor the antenna VSWR and the output power with an external power meter.
7.5 Now increase the drive level to nearly 40 watts to achieve nominal output power of more
1000 watts from the amplifier. Monitor the output power and if the antenna VSWR stays constant
(as higher RF current flow, some antennas may show a changed VSWR due to heated components
such as trap coils).
7.6 With a high power transceiver in SSB mode, you can overdrive the amplifier in a distorted
output signal. This can occur if you speak too loud or if you set the microphone (or compressor)
gain too high. Speak into the microphone properly to reduce the possibilities of spattering into the
neighborhood. You can reduce the RF output power, also.
7.7 Protection circuits may work during operation depending on the conditions. For more details
on this protection circuits, see section 13. PROTECTION CIRCUITS.
7.8 IMPORTANT NOTES:
- For high duty cycle transmissions like RTTY, it is advised that you use the intermediate
output power position (green LED "LOW" lit up).
- Due to the relatively low switching time of the TX-RX relays, we don't guarantee the use of
the transmission high-speed CW Full Break-in mode for speed more than 25-30 wpm.
- Required drive power is slightly less than 40 watts to obtain the full over 1000 watts output
power. Do not attempt to operate with drive power more than 40 watts.
- Absolutely never rotate the "BAND", STBY-OUT" and "ANTENNA" rotary switches
during operation.
PLUS
HVLA1K3 USERS MANUAL
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