Elecraft KXPA100 Manual - Manual (Page 15)

15
Personal Computer Interface Cable: All communications with both the KX3 transceiver and the
KXPA100 amplifier take place through this cable. This cable is not required, but provides enhanced
capability to operate the KXPA100 using the KXPA Utility program, for updating firmware in either
the KXPA100 or KX3 and other functions (see Utility Program, page 34 for details.) Also, this cable
provides communications between your PC and the KX3 through the KXPA100. You do not need to
connect the KX3 directly to your computer. Simply load the KX3 Utility program, be sure you have
the correct serial port selected, and your computer will find the KX3 as long as it is powered on.
RF Signal Connection between the KX3 and KXPA100: Use a 50-ohm coaxial cable with a PL-
259 (UHF male) connector for the amplifier RF IN and a BNC male connector for the KX3.
RF Connection to Antenna or Dummy Load: Normally a 50 ohm coaxial cable with a PL-259 (UHF
Male) connector leading to a 100 watt dummy load or antenna. A direct connection to an antenna wire
may be used here instead if it presents a low enough SWR or your KXPA100 is equipped with the
optional KXAT100 ATU (antenna tuner).There will be only one
ANT connector if you do not have the
optional KXAT100 ATU. The other position will be filled with a plug.
Adapter Cable Connection to the Amplifier: A 6-inch (15.2 cm) CAT 6 cable with RJ45 connectors is
included with the KX3 to KXPA100 Adapter Cable set. If needed, the cable supplied may be replaced
with a shielded CAT 6 cable up to 25 feet (7.6 meters) long.
Key Line Connection to the KX3: The ring terminal on the 2.5 mm stereo plug on the Adapter
Cable connects to the KX3 key line in the ACC2 connector. The KX3 grounds the key line while
transmitting to enable the amplifier.
Serial Data Connection to the KX3: The 3.5 mm stereo plug on the Adapter Cable connects to the ACC1
connector. The KX3 passes band, frequency and command data to the amplifier via this connection. The
KX3 turns the KXPA100 on and off and sends tuning commands to the KXAT100 ATU (if present).
CAUTION
Do not pull on the cables when they are plugged into the ACC1 or ACC2 connectors on
the KX3. The cables are equipped with right-angle connectors to minimize strain, but
rough handling can break the sockets in the KX3.
General Purpose Input-Output (GPIO): 3.5 mm mono connector that provides access to the KX3
GPIO normally available at the ACC2 jack. See your KX3 Owner’s Manual, especially the ACC2
IO entry under Menu Functions, for details of the GPIO.
Key Line Jack: RCA type female connector for the key line when the KXPA100 is used to drive a
higher-power amplifier.
CAUTION
If you are connecting the key line jack to a non-Elecraft amplifier, see Connections to an
External Amplifier on page 20. Failure to observe the instructions there could damage
your KXPA100.
PA Key Connector: Not used in this installation. The key line, which enables the amplifier during
transmit, is included in the adapter cable.