Kenwood TS-590S, Руководство по обслуживанию

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TS-590S
14
IF Filter
The IF fi lter includes a DSP digital fi lter as well as mul-
tiple analog fi lters in the IF stage to have suffi cient tolerance
for unnecessary signals.
In the RX-1 path with enhanced anti-proximate interfer-
ence, the MCF (XF301) and crystal fi lter (XF474, XF475) are
inserted for the fi rst IF (11.374MHz). In the RX-2 path, MCF
(XF371) for the fi rst IF (73.095MHz), a crystal fi lter (XF473)
or MCF (XF471, XF472) for the second IF (10.695MHz), and
a ceramic fi lter (CF591) for the third IF (455kHz: FM only).
Item XF301: L71-0656-15 XF474: L71-0657-05 XF475: L71-0658-05
Nominal center frequency 11.374MHz 11.374MHz 11.374MHz
Pass bandwidth ±3kHz or more at 6dB ±1.35kHz or more at 6dB ±250Hz or more at 6dB
Attenuation bandwidth ±17.5kHz or less at 60dB ±4kHz or less at 60dB ±0.75kHz or less at 60dB
Ripple 1dB or less 2dB or less 2dB or less
Insertion loss 3dB or less 6dB or less Within 6±3dB
Guaranteed attenuation 70dB or more at fo±1MHz 80dB or more at fo±1MHz 80dB or more at fo±1MHz
Center frequency deviation ±500Hz at 6dB ±150Hz at 6dB ±150Hz at 6dB
Terminating impedance 1k Ω // 6pF 900 Ω // 9pF 100 Ω // 90pF
Item XF371: L71-0605-05 XF472: L71-0230-15 XF471: L71-0664-05 XF473: L71-0569-15
Nominal center frequency 73.095MHz 10.695MHz 10.695MHz 10.695MHz
Pass bandwidth ±7.5kHz or more at 3dB ±7.5kHz or more at 3dB ±3kHz or more at 6dB ±1.35kHz or more at 6dB
Attenuation bandwidth ±35kHz or less at 40dB ±25kHz or less at 18dB ±40kHz or less at 60dB ±300kHz or less at 60dB
Ripple 1dB or less 0.5dB or less 2dB or less 2dB or less
Insertion loss 3dB or less 2dB or less 3dB or less 6dB or less
Guaranteed attenuation
70dB or more at
fo+(500~1000kHz)
70dB or more at
fo–(200~1000kHz)
30dB or more at fo±1MHz 60dB or more at fo±1MHz
60dB or more at
fo±300kHz
Center frequency deviation ±1.5kHz at 3dB - ±1kHz at 6dB ±150Hz or less at 6dB
Terminating impedance 2.5k Ω // –0.5pF 3k Ω // 2pF 1.2k Ω // 6pF 1.2k Ω // 7pF
Item CF591: L72-0998-05
Nominal center frequency 455kHz
Pass bandwidth ±6kHz or less at 6dB
Attenuation bandwidth ±12.5kHz or less at 50dB
Ripple 2dB or less
Insertion loss 6dB or less
Guaranteed attenuation
35dB or more at
fo±100kHz
Center frequency deviation ±1.0kHz
Terminating impedance 2k
Ω
Table 6 IF fi lter
CIRCUIT DESCRIPTION