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example, if the RF. GAIN control is set for no signal reading of S8 and reads S9 with signal, the received signal is S9.
2.2.2 FSK Operation.
The KWM-2/2A Transceiver has an audio response of 300- to 2400-Hz nominal, therefore any FSK audio input must be between 300 and 2400 Hz.
Usually in RTTY, the FSK signal is an 850-Hz total shift between mark and space signals. This shift is most often obtained by providing a 425-Hz shift to either side of a reference frequency. The reference frequency is the RTTY center frequency. To obtain the 850Hz shift and reference frequency using the KWM-2A, follow the procedures listed below.
During RTTY operation of the KWM-2/2A a small blower must be directed on the power amplifier cage to permit continuous operation.
Connect this plug to the ALC phone jack (J4) to provide a short to ground for the ALC line.
VOX and anti VOX circuits will operate in mobile operation, but push-to-talk operation is ecommended, since high-level background noises will produce undesirable VOX switch over. Set VOX GAIN and ANTIVOX GAIN controls full counterclockwise before installation. If VOX operation is desired, leave clearance in installation so top cover can be opened. For mobile operation, load the power amplifier to 210-mA plate current. (In some installations, power amplifier plate current readings less than 210 mV will he obtained due to cable length, cable size, and battery condition.)
2.5 OPERATION OUTS1DE AMATEUR BANDS
2.5.1 Selection of Crystals
The crystals supplied provide for complete coverage of all amateur bands except the 10 meter band for which only one crystal is furnished for 28.5 to 28.7 MHz). Two extra sockets are provided for additional crystals in the 10-meter band. figure 2-3 shows crystal socket locations. Select these crystals as follows: