
TRANSCEIVER OPERATION
Installing Band Modules:
Prior to powering up, identify and install the filter module for
the band you intend to use. The band is marked on the filter pc board. To access plug-in
headers for the module, remove the two knurled screws securing the radio’s case and
slide off the back.
Antenna
Module Header
Module Header
Standoff
Antenna
Band Label
Module
Screw
Band Module
The band-module headers are located directly below the BNC antenna connector. Line
up the module and install it component-side down, as shown. Fasten in place using the
module retention screw and reinstall the case.
Note that the retention screw should
always be used to ensure firm seating and good grounding.
Also, note that a filter
module must be installed for the DDS to recognize a band of operation.
Key Detection:
The MFJ-9200 features a key-detection circuit. The sensing circuit
initializes
each time the radio is powered up
. If paddles are connected or if no key is
installed, the keyer initializes in
Automatic Mode
and sends the letter
A
in code. If a
straight key is installed when the radio is powered up, the keyer senses
Manual Mode
and sends the letter
M
.
Important Note:
The radio’s default is
Automatic Mode
. If a manual key is plugged in
after the radio is powered up
, the radio will transmit a continuous string of dashes until
the key is unplugged or the radio is rebooted. This condition occurs because the keyer
misinterprets the manual key’s monaural plug as a ring-to-sleeve contact closure. To
correct it, simply switch the power off and turn it back on again to re-initialize the keyer.
Power On:
After connecting a power source, antenna, headphones and key, you’re
ready to begin. It may prove helpful to have your radio set up and connected to a
dummy load when going through this portion of the manual so you can check out each
function without causing on-air interference. Using the
POWER
switch located on the
front panel, power up the radio and set
VOLUME
for a comfortable listening level.
Boot Screen:
During power-up, the LCD screen displays the selected band. Example:
[
Band-20m
]. Also, the keyer side-tone sends the letter
A
or
M
in code to identify the
type of key that is plugged in.