The KPA500 RS-232 connector must be connected to a personal computer serial port before firmware can be sent to the KPA500. If no RS-232 serial port is available, a USB to Serial Adapter, such as the Elecraft KUSB, may be used instead.
The KPA500 back panel has two 9-pin D-shell connectors. Connect the Personal Computer to the upper (female) DE-9 connector.
A 9-pin "straight through" male-to-female DB-9 serial cable is recommended.
Do not use a "crossover" or "null modem" cable.
The cable must have a minimum of three wires: Transmit Data, Receive Data, and Ground. Other RS-232 lines (e.g., Request to Send, Clear to Send, Data Set Ready, Data Terminal Ready) are not used by the KPA Utility.
The female 9-pin D-shell RS-232 connector on the KPA500 back panel has jack nuts, so the male end of your serial cable should have screws.
If your computer does not have an available serial port, a USB to Serial Adapter such as the Elecraft KUSB may be used. The Elecraft KUSB has screws that attach directly to the jack nuts on the KPA500 back panel RS-232 connector.
If your USB to Serial Adapter has jack nuts on its 9-pin connector, a short serial male-to-female DB-9 serial cable with screws on each end, such as the one pictured above, may be necessary between the USB to Serial Adapter and the KPA500 back panel RS-232 connector.
Choose a "real" RS-232 serial port if one is available on your computer.
