Timewave DSP-232, Руководство по эксплуатации

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Chapter 9 AMTOR Operation
(If you’re using an AEA program, follow the instructions in the program’s manual to set up and use AMTOR.)
AMTOR is a bit more complex than Baudot or ASCII operation. AMTOR operating modes require SELCALL
(SELective CALL) codes to be entered before you can operate in this mode.
The SELCALL is a unique character sequence, consisting of four alphabetic characters, that’s derived from your
callsign; your DSP will convert your call for you using
MYSELCALL . In the following example, we’ll use
KB6IUX to generate a SELCALL:
cmd:
MYS KB6IUX
MYSelcall was none
MYSelcall now KIUX
cmd:
Because the same callsign sequences are assigned in ten districts, it’s possible that your SELCALL could be used by
another station. If that should happen, see
MYSELCALL
for information on how to change your SELCALL or use
MYIDENT below.
Most of the AMTOR activity on the amateur bands uses a four-character SELCALL as described above. A seven-
character SELCALL, using
MYIDENT
, is available to solve the problem of coincidental SELCALLs by providing
many more possible combinations. To obtain your seven-character SELCALL, all you have to do is enter your
amateur callsign as in the example below:
cmd:
MYI KB6IUX
MYIdent was none
MYIdent now KBDIUXX
cmd:
We suggest you create both a 4- and 7-character SELCALL.
Now that you’ve entered your
MYSELCAL
and
MYIDENT
SELCALL codes, you’re ready to enter the AMTOR
mode by simply entering AMTOR or AM at the Command prompt. The DSP responds by displaying the previous
mode it was in, then its new mode:
cmd:
AM
Opmode was
(
previous mode
)
Opmode now AMtor
cmd:
Look at your DSP’s front panel to verify that you’re in the AMTOR mode—the symbol ‘A’ will be shown in the
Mode window.
Next, you can choose which modem you want to use using the
MODEM command, followed by the specific modem
number. For a list of modems available in the DSP, type
DIRECT
at the
cmd:
.
Once you have selected the mode, and modem the next step is to set your radio to LSB unless you’ve connected
your DSP to your radio’s direct FSK keying lines. If you have, then you should select the FSK operating mode on
your radio.
Receiving AMTOR
Most AMTOR operation occurs on the 20-meter band between 14.065 and 14.085 MHz, though activity can also be
found on the other HF amateur bands as well; it’s often located between 65 KHz and 90 KHz up from the bottom of
the band as it is on 20 meters.
Tuning in AMTOR stations properly is the key to successful operation. Since HF AMTOR stations use either 170
Hz or 200 Hz Frequency Shift Keying to send data, tuning accuracy is very important. Follow the procedure below
for the best results.
9-2 September, 05