Epson MFJ-1278B Benutzerhandbuch

The MFJ-1278B allows radio connection without any modifications to the radio or any signal 
balancing devices in the cables.  There are two types interfacing methods presented in this 
chapter. 

For Method 1, shown in Fig. 3-5, the MFJ-1278B's audio is fed directly into the microphone 
connector or similarly connected auxiliary jack.  The output of the MFJ-1278B will be 
adjusted to give a proper modulation level.  The receiver audio will be taken from an 
earphone plug or speaker jack and fed directly to the MFJ-1278B.  The user can connect a 
monitor speaker to the SPEAKER jack of the MFJ-1278B. This  allows you to monitor the 
transmit and receive audio on the channel. 
 

 

 

 
The transmit audio levels for both radio ports are factory preset at 250 mV p-p to be 
compatible with the mic input of most radios.  However, if the transmit audio is too low or 
distorted, then adjust the appropriate output level control as stated in the section.  Use the 
following procedure to calibrate: 

Transmit Audio Level Adjustment for Method I Interface 

1. 

Connect your MFJ-1278B and radio as shown in Fig. 3-5. Turn on the  MFJ-1278B and 
computer and start your terminal program.  Connect the radio to a dummy load and 
listen to the transmission with another nearby radio. 

 
2. 

Enter the modem calibration procedure by typing 

followed by a carriage return.  Press the K key on your keyboard to key the transmitter, then