Kenwood TS-990S Service Manual page 54

TS-990S
Ref. No. Use/Function
Q55 Amplifi er
Q56 Switching
Q57 Switching
Q58 Switching
Q59 Switching
Q60 Switching
Q61 Switching
Q62 Switching
Q63 Switching
Q64 Switching
Q65 Switching
Q66 Switching
Q67 Switching
Q68 Switching
Q69 Switching
Q70 Amplifi er
Q71 Switching
Q72 Switching
Q73 Switching
Q74,75 Switching
Q76 Switching
Q77 Switching
Q501 Switching
Q502 Switching
Q503 Switching
Q504 Switching
54
COMPONENTS DESCRIPTION
Operation/Condition/Compatibility
MLO2 amplifi er
ON when 15kHz IF fi lter is se-
lected (ON when MFIL1 is "H")
ON when 6kHz IF fi lter is se-
lected (ON when MFIL2 is "H")
ON when 2.7kHz IF fi lter is se-
lected (ON when MFIL3 is "H")
ON when 500Hz IF fi lter is select-
ed (ON when MFIL4 is "H")
ON when 270Hz IF fi lter is select-
ed (ON when MFIL5 is "H")
ON when additional IF fi lter is
selected (ON when MFIL6 is "H")
ON when 500Hz IF fi lter is select-
ed (ON when MFIL4 is "H")
ON when 270Hz IF fi lter is select-
ed (ON when MFIL5 is "H")
ON when additional IF fi lter is
selected (ON when MFIL6 is "H")
ON when main FM narrow is se-
lected (ON when M455FIL is "L")
ON when 15kHz IF fi lter is se-
lected (ON when MFIL1 is "H")
ON when 6kHz IF fi lter is se-
lected (ON when MFIL2 is "H")
ON when 2.7kHz IF fi lter is se-
lected (ON when MFIL3 is "H")
ON when main FM wide is select-
ed (ON when M455FIL is "H")
AGC amplifer
Receiver output, FM (AF) and
SSB/AM/CW (IF) changeover
multipulexer (IC11) control
ATT switch for NB mode (ON
when except NB mode (NBS is
"L"))
Noise blanker changeover relay
(K17) control (ON when NBS is
"H")
ON when MBPF14 is "H", except
MPRE1 or MPRE2 is "H"
ON when BPF of 35~40MHz is
selected (ON when MBPF14 is
"H")
Blanking switch
ON when BPF of 2.5~4.1MHz is
selected (ON when MBPF4 is "H")
ON when BPF of 6~7.5MHz is
selected (ON when MBPF6 is "H")
ON when BPF of 10.5~14.5MHz
is selected (ON when MBPF8 is
"H")
ON when BPF of 18.5~21.5MHz
is selected (ON when MBPF10 is
"H")
Ref. No. Use/Function
Q505 Switching
Q506 Switching
Q507 Switching
Q508 Switching
Q509 Switching
Q510 Switching
Q511 Switching
Q512 Switching
Q513 Switching
D1 Surge protection
D2,3 Surge absorption
D4,5 Surge absorption
D6 Switching
D7,8 Surge absorption
D10,11 Surge absorption
D12 Switching
D13 Switching
D14 Switching
D15 Surge absorption
D16 Switching
D17~20 Surge absorption
D21 Detection
Reverse current
D22,23
prevention
D24 Switching
D25 Surge absorption
Noise blanking
D26~29
(Mute)
D30 Attenuator
D31 Switching
Operation/Condition/Compatibility
ON when any one of MBPF5, 7,
9, 11, 12, 13, 14 is selected (ON
when NRLY is "H")
ON when BPF of 1.705~2.5MHz
is selected (ON when MBPF3 is
"H")
ON when BPF of 4.1~6MHz is
selected (ON when MBPF5 is "H")
ON when BPF of 21.5~26.5MHz
is selected (ON when MBPF11 is
"H")
ON when BPF of 26.5~35MHz is
selected (ON when MBPF12 is
"H")
ON when BPF of 7.5~10.5MHz is
selected (ON when MBPF7 is "H")
ON when BPF of 40~46.5MHz is
selected (ON when MBPF13 is
"H")
ON when BPF of 46.5~60MHz is
selected (ON when MBPF14 is
"H")
ON when BPF of 14.5~18.5MHz
is selected (ON when MBPF9 is
"H")
Main reciever RF signal input
Relay (K1/K2)
Internal circuit protection
6dB attenuator switch (ON when
MBPF14 is "H", except MPRE1 or
MPRE2 is "H")
Internal circuit protection
Relay (K3/K4)
ON when BPF of 522k~1.705MHz
is selected
ON when BPF of 30~522kHz is
selected
ON when BPF of 522k~1.705MHz
is selected
Relay (K5)
ON when BPF of 30~522kHz is
selected
Relay (K6~K9)
Noise blanker switching pulse
detection
MBLNK control line
Select of MLO2 output
Relay (K10)
ON when MBLNK signal is "H"
IF gain adjustment
Select of 2nd IF signal output