SCS PACTOR III, Руководство по установке

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3. Installation
42
- For HF and 1k2 Packet-Radio:
Signal PTC Color YAESU
GND PIN 2 white PIN 2
PTT PIN 3 yellow PIN 3
AF-OUT PIN 1 violet PIN 1
AF-IN PIN 4 green PIN 5
This cable is available completely assembled.
Refer to chapter 5 on page 49 .
Table 10: YAESU 6 pin Mini-DIN
- For 9k6 Packet-Radio:
Signal PTC Color YAESU
GND PIN 2 white PIN 2
PTT PIN 3 yellow PIN 3
AF-OUT PIN 1 violet PIN 1
AF-IN PIN 4 green PIN 4
This cable is available completely assembled.
Refer to chapter 5 on page 49 .
Table 11: YAESU 6 pin Mini-DIN
3.5.4 Amplitude Adjustment
The PTC’s output amplitude has to be adjusted very carefully to the connected transceiver. If
you don’t pay attention on this item, a signal much too wide will be the result!
The output amplitudes are adjusted separately depending on the FSK modes (PACTOR-I,
AMTOR, RTTY, etc.) and the PSK modes (PACTOR-II/III). A common adjustment with one
command was in practice not the best way.
The audio input sensitivity of most transceivers is adapted to the output voltage of a common
dynamic microphone. 100% modulation is reached at low mic gain settings with 200 mV (peak
to peak) input voltage. It is not recommended to use very high
PSKAmpl
values and
compensate this by lowering the mic gain setting, because this may already overdrive the first
amplifier stages which are very sensitive and located in the signal path before the mic gain
controlling device. We recommend for the first approach to use the default PSKA value of 140
and then regulate the output power for PSK with the mic gain setting (if available). To do this,
connect the TRX to a dummy load resistor, capable to dissipate the power or to an antenna with
good SWR (take care that the frequency being used is not already occupied). Entering
U
3
<Return> starts the Unproto mode 3 (=100 Bd DBPSK). Now you can use the mic gain knob to
increase the transmitting power until the ALC voltage reaches the allowed limit.
Don’t overdrive the TRX because in this case the signal will be spreaded by intermodulation!
With proper settings, the peak envelope power will nearly be equal to the maximum output
power of the TRX. In this case, the average power will approximately be the half of the
maximum power, so also continuous operation will not cause problems at all. Don’t be
confused as many modern TRX only display the peak envelope power. If it is necessary to set