2: System Overview
PRC1099A-MS
2-5
2.5.4
Power Amplifier Board
On the Power Amplifier (PA) board, the high-power final RF power
amplifiers that consist of a Class A pre-driver, a push-pull driver stage, and a
push-pull final output stage boost the transmit signal to its final RF output
power or approximately 20W in high power mode or 5W in low power mode.
The PA board uses special broadband transformers for interstage and output
coupling. From the PA board, the SSB channel frequency signal is routed back
to the Audio/Filter board.
2.5.5
Audio/Filter Board Transmit Path 2
On the Audio/Filter board, the 20W transmit signal transmit signal is applied
to one of six separate high-performance, elliptical-function filters that provide
effective attenuation of the harmonic spectrum. The processor selects the filter
based on the selected channel. The signal passes through the ALC detector
and is routed to the Antenna Tuner board.
2.5.6
Automatic Antenna Tuner Transmit Path
The Antenna Tuner board uses detectors at the transmit signal input and
follows a tuning routine, controlled by the processor, to match the radio output
impedance to the antenna for maximum output. To protect the RF power
amplifiers from damage, the output is automatically switched to the 50 ohm
antenna connector when the whip or long-wire antenna is removed.
2.6
DC Power
The PRC1099A operates from a 12 to 15 VDC supply source. The critical
circuitry operates from the regulated 8V and 5V supply lines. The higher
power circuitry operates directly from the 12V supply but continues to operate
down to 10.5V with only minimal reduction in performance specifications.
Table 2-1 Board Functionality
Function
Path
Description
I/O
Audio/Filter Board
VOGAD - U8C
Transmit
Amplifies microphone input and
automatically controls gain.
Input from front-panel handset.
Output to balanced modulator
U6.
Balanced
Modulator - U6
Transmit
Generates DSB 1650 kHz signal,
suppresses carrier.
Input from VOGAD.
Output to J10 to 1650 kHz IF
board.
Product Detector
- U4
Receive
Demodulates 1650 kHz SSB
signal.
Input from 1650 kHz IF board
amplifier.
Output to squelch and audio PA.
BFO input from Synthesizer
board.
Содержание PRC1099A
Страница 4: ......
Страница 8: ......
Страница 35: ......
Страница 49: ...3 Audio Filter Board 3 14 PRC1099A MS Figure 3 2 Audio Filter Board Component Locations 738221 Rev J ...
Страница 65: ......
Страница 71: ...4 1650 kHz IF Board 4 6 PRC1099A MS Figure 4 2 1650 kHz IF Board Component Locations 738028 Rev D ...
Страница 76: ......
Страница 86: ...5 Mixer Board 5 10 PRC1099A MS Figure 5 4 Mixer Board Component Locations 738217 Rev H ...
Страница 97: ......
Страница 103: ...6 Power Amplifier Board 6 6 PRC1099A MS Figure 6 2 Power Amplifier Board Component Locations 738617 Rev C ...
Страница 117: ...7 Antenna Tuner Board PRC1099A MS 7 9 Figure 7 2 Antenna Tuner Driver Board Component Locations 738346 Rev B ...
Страница 118: ...7 Antenna Tuner Board 7 10 PRC1099A MS Figure 7 3 Antenna Tuner Board Component Locations 738027 Rev D ...
Страница 125: ......
Страница 131: ...8 Synthesizer Board 8 6 PRC1099A MS Figure 8 2 Synthesizer Board Component Locations 738025 Rev A ...
Страница 163: ...9 Processor Board 9 14 PRC1099A MS Figure 9 2 Processor Board Component Locations 738218 Rev B ...
Страница 178: ...10 Display Board 10 8 PRC1099A MS Figure 10 1 Display Board Component Location Diagram 738220 Rev G ...
Страница 181: ......
Страница 185: ...11 Junction Board 11 4 PRC1099A MS Figure 11 1 Junction Board Component Locations 738222 Rev F ...
Страница 200: ......
Страница 207: ...13 Internal Options PRC1099A MS 13 7 Figure 13 3 ALE Board Component Locations 1 of 2 738215 Rev B ...
Страница 208: ...13 Internal Options 13 8 PRC1099A MS Figure 13 4 ALE Board Component Locations 2 of 2 738215 Rev B ...
Страница 241: ......
Страница 247: ...Index 6 T Technical specifications 1 2 Transmit path 2 4 U USB 1 4 see also Modulation modes USB LSB mode V VSWR 1 4 ...