Epson Multi-mode Data Controller MFJ-1278B Benutzerhandbuch

Seite von 406
MFJ-1278B MULTI-MODE                                     BASIC OPERATION 
To enter the converse mode type: 
This will take the MFJ-1278B out of the command mode and into converse mode.  When the 
MFJ-1278B enters converse mode, the STA will illuminate.  Also after entry into converse 
mode the MFJ-1278B is in receive mode.  You can enter transmit mode by typing 
CONTROL-T.  To re-enter receive mode type a CONTROL-R  The command CONTROL-
C
 will return you to the command mode, where you will get the cmd: prompt on your screen.  
Use lower side band, LSB unless you have an RTTY position on your rig.  Tune your radio 
until the 10th or 11th segments on the tuning indicator light during receive.  Ensure that the 
yellow DCD led is illuminated also during receive.  It is possible to tune to the center of the 
bar graph, and not have the DCD led lit.  If the DCD led does not light, then check the setting 
of the Threshold control on the front panel.  The DCD led needs to be lit for reception.  Some 
bouncing of the LED is normal, since any audio other than the signal (QRM/QRN) will also 
affect how it responds.  From the converse mode you should now see text being printed on 
the screen as it is heard.  Contacts usually take place on a one-way at a time basis.  So one 
side will transmit and the other will receive, and then the sides are reversed. 
 
To allow the MFJ-1278B to transmit RTTY or ASCII, type: 
CTRL-T 
while in converse mode to key the PTT on the radio.  The green PTT light should light and 
you should see power on your wattmeter.  All keystrokes are now sent out over the air.  
Alpha-numeric (numbers and upper/lowercase letters) characters are the only kind of 
keystrokes accepted.  Some punctuation is allowed.  When the transmission standards were 
set up, only mechanical typewriters (tele- type) were used and these were the only keys in 
use.  Most other characters such as Greek and graphics are usually translated wrong, and 
you'll see the other guy's 'mistakes' when he types one of the characters.  To go back to the 
receive mode, type CTRL-R in converse mode to unkey the radio, and you will return to the  
receive mode.  This will start the transmit/receive cycle over. 
Commercial RTTY Reception 
Commercial RTTY presents a special problem for amateurs and short wave listeners.  Several 
conditions must be met before you can get a decent printout.  You have to locate the 
frequency of a particular station, get the schedule right, pick the sideband, set the baud rate, 
set the frequency shift, and finally, unencrypt the text. 
 
You can receive many of these stations using the 425 shift, 50 baud, and lower sideband 
during the daylight hours.  For this setup use MODE VB,50.  Some military frequencies are 
unencoded, as well as some of the UPI broadcasts.  A good source of frequencies is Popular 
Communications and Monitoring Times magazines.