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3-7-22 BUFFER IC (MAIN UNIT; IC251)
11
TXB7
Outputs the bandpass filter (B7)
selecting signal during transmit.
High : While transmitting on
11–15 MHz.
12
TXB6
Outputs the bandpass filter (B6)
selecting signal during transmit.
High : While transmitting on
8–11 MHz.
13
TXB5
Outputs the bandpass filter (B5)
selecting signal during transmit.
High : While transmitting on
6–8 MHz.
14
TXB4
Outputs the bandpass filter (B4)
selecting signal during transmit.
High : While transmitting on
4–6 MHz.
15
TXB3
Outputs the bandpass filter (B3)
selecting signal during transmit.
High : While transmitting on
3–4 MHz.
16
TXB2
Outputs the bandpass filter (B2)
selecting signal during transmit.
High : While transmitting on
2–3 MHz.
17
TXB1
Outputs the bandpass filter (B1)
selecting signal during transmit.
High : While transmitting on
1.6–2 MHz.
18
TXB0
Outputs the bandpass filter (B0)
selecting signal during transmit.
High : While transmitting on
0.03–1.6 MHz.
Pin
Port
Description
number
name
3-7-23 BUFFER IC (MAIN UNIT; IC261)
12
AMS
Outputs the transmit output power
control signal.
High : Transmitting in AM mode.
13
50MS
Outputs the transmit output power
control signal.
High : Transmitting in 50 MHz band.
14
HFS
Outputs the HF band transmitting
power control signal.
16
TXB10
Outputs the bandpass filter (B10)
selecting signal.
High : While transmitting on
30–60 MHz.
17
TXB9
Outputs the bandpass filter (B9)
selecting signal.
High : While transmitting on
22–30 MHz.
18
TXB8
Outputs the bandpass filter (B8)
selecting signal.
High : While transmitting on
15–22 MHz.
Pin
Port
Description
number
name
3-7-24 SERIAL/PARAMETER IC
(RXPLL-A UNIT; IC1)
4
PST2A
Outputs the strobe signals to the 1st
LO PLL IC on the RXPLL-A unit.
5
PST1A
Outputs the strobe signals to the 1st
LO DDS IC on the RXPLL-A unit.
6
PST3A
Outputs the strobe signals to the 2nd
LO DDS IC on the RXPLL-A unit.
7
PST4A
Outputs the strobe signals to the T3
LO DDS IC on the RXPLL-A unit.
Pin
Port
Description
number
name
3-7-25 SERIAL/PARAMETER IC
(RXPLL-B UNIT; IC1)
4
PST2B
Outputs the strobe signals to the 1st
LO PLL IC on the RXPLL-B unit.
5
PST1B
Outputs the strobe signals to the 1st
LO DDS IC on the RXPLL-B unit.
6
PST3B
Outputs the strobe signals to the 2nd
LO DDS IC on the RXPLL-B unit.
7
PST4B
Outputs the strobe signals to the T3
LO DDS IC on the RXPLL-B unit.
Pin
Port
Description
number
name
3-7-26 DDS IC (RXPLL-A UNIT; IC101)
67
MUTA
Outputs the 1st LO muting signal to
the RXPLL-A unit.
High : While muting.
68
VA6S
Outputs the 1st LO VCO (VCO6) con-
trol signal to the RXPLL-A unit.
High : While receiving on 45–60 MHz.
70
VA5S
Outputs the 1st LO VCO (VCO5) con-
trol signal to the RXPLL-A unit.
High : While receiving on 30–45 MHz.
71
VA4S
Outputs the 1st LO VCO (VCO4) con-
trol signal to the RXPLL-A unit.
High : While receiving on 22–30 MHz.
73
VA3S
Outputs the 1st LO VCO (VCO3) con-
trol signal to the RXPLL-A unit.
High : While receiving on 15–22 MHz.
74
VA2S
Outputs the 1st LO VCO (VCO2) con-
trol signal to the RXPLL-A unit.
High : While receiving on 8–15 MHz.
75
VA1S
Outputs the 1st LO VCO (VCO1) con-
trol signal to the RXPLL-A unit.
High : While receiving on 0.03–8 MHz.
Pin
Port
Description
number
name
Summary of Contents for IC-7800
Page 1: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 65 VOLTAGE DIAGRAM 67 Dec 2009 ...
Page 79: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 60 VOLTAGE DIAGRAM 64 Feb 2009 ...
Page 157: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 57 VOLTAGE DIAGRAM 59 Aug 2008 ...
Page 245: ...SERVICE MANUAL ADDENDUM CONTENTS PARTS LIST 1 BOARD LAYOUTS 57 VOLTAGE DIAGRAM 59 Jul 2008 ...
Page 333: ...THE TRANSCEIVER i7800 SERVICE MANUAL S 14015HZ C1 2 Mar 2006 ...
Page 555: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan S 14015HZ C1 2 C 2004 2006 Icom Inc ...