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Circuit Description
ed to the pin 8 of the PLL IC. Also the output of the VCO
is amplified by the Q1021 and routed first local /Power
Module according to D1022.
The PLL IC consists of a prescaler, reference divider and
phase comparator. The input signal from pin 1 and 8 of
the PLL IC is divided down to the 5kHz or 6.25kHz and
compared at phase comparator. The pulsed output signal
of the phase comparator is applied to the charge pump
(Q1036, Q1037) and transformed into DC signal in the loop
filter. The DC signal is applied to the VCO and locked to
keep the VCO frequency constant.
PLL data is output from DATA (pin42), CLOCK (pin41)
and PLL_E (pin7) of the microprocessor Q2013. The data
are input to PLL IC when the channel is changed or when
transmission is changed to reception and vice versa. A
PLL lock condition is always monitored by the pin14 of
the Q2013. When the PLL is unlocked, the UL goes low.
6. Miscellaneous Circuits
6-1 DCS Encorder
The DCS code is generation and encoding by Microcom-
puter Q2013 (
by Q2020 (
) and adjusted the level by Q2014
(
).
6-2 DCS Decoder
The received DCS signal is filtered by Q2016 (
and amplified by Q2015 (
by Q2021 (
). The signal is applied to the pin 6
of the Microcomputer Q2013 (
6-3 CTCSS encoder/decoder
Q2016 (
) encodes and decodes the CTCSS signal.
6-4 5-Tone Encorder
The 5-Tone is generated from Pin1 to Pin 4 of Microcom-
puter Q2013 (
by Q2022 (
).
6-5 5-Tone Decoder
The 5-Tone is compared by Q2015 (
nal is applied to the pin 5 of the Microcomputer Q2013
(
) for its decoding.
6-6 Microcomputer
Operation is controlled by 8-bit Microcomputer Q2013
(
). The system clock uses a 7.3728MHz crys-
tal for a time base. IC Q2003 (
the MPU when the power is on, and monitors the voltage
of the regulated 5V power supply line.
6-7 Compander
The Compander Q2017 (LA8630M)is active when Pin2 of
Q2029 (
) is "High". When the Compander is
active, MIC Audio is compressed, and detected audio is
expanded by Q2017 (
10
). It is filtered and amplified
), then after compared
).
). It is filtered and amplified
). The sig-
) resets
).
7. Power Supply Circuits
7-1 All 13.2V
13.2V is always supplied to Power AMP Q1014
(RA30H1317M). Switched 13.2V is supplied to AF Power
AMP Q1509 (TDA2003H) and 9V Regulator Q1004
(MM1216EN) and Q1005 (2SB1201STP).
7-2 All 9V
9V regulated from 13.2V by Q1004 (MM1216EN) and
Q1005 (2SB1201STP).
7-3 VCO 9V
9V is filtered by Ripple Filter and is supplied to VCO Os-
cillator Q1013 (2SK508-K52), Q1015 (2SC4226-R24), and
VCO BUFFER AMP Q1018 (2SC5107-O).
7-4 5V (RF-UNIT)
5V in RF-UNIT is regulated by REGULATOR IC Q1024
(NJM78L05UA). 5V is supplied to PLL IC Q1038
(MB15A02PFV1), FM IC Q1028 (TA31136FN).
7-5 TX 9V
TX 9V is active on transmit. TX 9V is supplied to ANT SW
D1005, D1007 (UM9957F) and TX DRIVER Q1022
(2SC5415E), Q1025 (2SC5107-O).
7-6 RX 9V
RX 9V is active on receive. RX 9V is supplied to RX RF
AMP Q1011 (2SC4226-R24) and MIXER Q1026
),
(SGM2016AM).
7-7 5V (RF-UNIT)
9V from RF-UNIT is regulated to 5V by REGULATOR IC
Q2006 (NJM78L05UA) in PANEL-UNIT.
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