Pulsar TC-10B, Руководство пользователя

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• SW1 (x 100kHz)
• SW2 (x 10kHz)
• SW3 (x 1kHz)
• SW4 (x 0.1kHz)
After pulling the module, use a screw driver to set
the thumbwheel switches: CW for higher
frequency, CCW for lower frequency.
11.1.2 Transmitter PC Board
(The Transmitter PC Board is shown in
Figure 11-3.)
Operator controls are as described below.
Potentiometers
R13 Adjusts high-level (10W) output
R12 Adjusts low-level (1W) output
R14 Adjusts voice (4.3W) output level
R1 Adjusts modulation of transmitter
signal (peak-to-valley ratio of signal
envelope)
R29 Sets the offset in output amplifier, so
that when 0dBm is generated, R29 is
adjusted to minimize the 2nd harmonic
distortion
Capacitor
C19 Adjustment for 3.27680MHz clock
oscillator
Switch
S5 No shift used on TC-10B
Test Point
TP1 Clock Oscillator Output
11.2 Transmitter Circuit
Description
The function of the Transmitter Module (see
Figure 11-4, Schematic 1355D71) is to provide
the RF signal (0dBm/.001W, 50
Ω
balanced),
which drives the 10W PA Module. The
Transmitters frequency range is from 30kHz to
535kHz, programmable in 0.1kHz (100Hz) steps
by four rotary switches on the Transmitter. The
Transmitter Module operates from keyed inputs
(set by jumpers at the Keying Module):
• High-Level (10W) Key (pins C/A-8)
• Any Transmitter Key (pin A-10)
• Voice Key (pins C/A-6)
• Shift High (pin C-10) (TCF–10B Only)
• Shift Low (pins A/C 24) (TCF–10B Only)
The Transmitter Module also operates from an
audio signal from the Optional Voice Adapter
Module: AM Voice (pins C/A-26). Refer to Figure
11-5, Transmitter Block Diagram.
Frequencies are selected using the four BCD
(Binary Coded Decimal) switches (SW1 thru
SW4); the range is from 30.0 to 535.0kHz, in
0.1kHz (100Hz) steps. The 15-bit output of the
BCD switches is converted to a 13-bit binary
number by the BCD-to-Binary converter (ROMs
I1 and I2).
The 13-bit output of ROMs I1 and I2 provides an
input to the Shift and Control Logic (I3), which
consists of three parts:
1. A full adder/subtracter which functions under
control of:
• Shift High (Add)
• Shift Low (Subtract)
2. A frequency-shift, in 50Hz increments from 0
to 750Hz, selected by the 4-position dip-
switch (S5).
3. A sequencer and multiplexer (MUX) which
provides the following outputs to the
Numerical Controlled Oscillator (NCO I4):
• Address select (ADDR)
• Write (WRN)
• Load (LDSTB)
• 2 (8-bit sequential) data bytes
The NCO (I4) generates digital sine functions of
very precise frequency, to be used in conjunction
with a D/A converter (I5) in analog frequency
Page 11–2 October 2003
TC–10B System Manual
Technologies, Inc.