Kenwood KT 1100 SD Service Manual

Page 2

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Operation of active elements
Tuner unit (X05-2810-1li

Element Function Oplration (compatible)
1C1 1/2 DCC distortion component adder
lCl 2/2 PLL detector DC amp
lCZ 1/2 Noise amp Amplifies the noise detection component of more than approx. 150kHz,
IC2 2/2 Band, noise muting detection With no input or incomplete detuning. output ® is -llV at © < © .
comparator With normal tuning, it is + 11V at ® > © , (AN6556l
its Multiplier Multiplies the composite signals Ifrom the detector by each other to generate the
secondary distortion elimination signal.
_ . Muttiplies the secondary distortion signals generated at IC3 and IC6 and the composite
lC4 Multiplier _ _ _ . »
signal. to generate the tertiary distortion elimination signal.
, . Multiplies the secondary distortion signals generated at lC3 and 1C6 by each other to
|C5 Multiplier I _ . . . I
generate the quaternary distortion elimination signal.
lCG 2/2 Current-voltage conversion Converts the current output of lC3 lmultiplierl into a voltage output.
IC6 1/2 Secondary distortion signal amp The variable gain amp which changes the correction amount of distortion correspond-
lng to FM-IF band selection. (NJM4560)
|C7 1/2 Current-voltage conversion Converts the current output of IC4 into a voltage output.
IC7 2/2 Currentvoltage conversion Converts the current output of Hill into a voltage output. iNJMASBO)
DET distortion correcting differential , . _ L
IC8 1/2 amp Changes the differential balance by VRl to vary the gain and phase.
lCS 2/2 . Secondary stereo thh only) Changes the differential balance by VR3 to vary the gain and phase. (NJM4560l
distortion correCtion differential amp .
1C9 1/2 Secondary MONO distortion Changes the differential balance by V82 to vary the gain and phase.
correction differential amp
lC9 2/2 OuaternaryIdisrortion (primary Changes the differential balance by VRG to vary the gain and phase. lNJM4560l
differentiation) correction
differential amp
lC10 1/2 Tertiary Stereo,(SUB fjlsmmon Changes the differential balance by VHS to vary the gain and phase.
correction differential amp
Quaternary distortion (secondary
lClO 2/2 differentiation) correction Changes the differential balance by VH7 to vary the gain and phase. (NJM4560)
differential amp
Forms the feedback loop by 2 integrators (l/Zl and (2/2l for oscillation. The output
IC11 REC CAL OSC integrator of l2/2i is a sine wave. At OFF, the voltage at pin (5) rises by 046 and the voltage at
pin ® is fixed to +11V so that OSC stops. (AN6556l
IC12 1/2 Pilot cancel signal inversion amp
Composite signal-REC CAL signal REC CAL OFF : Adds the composite signal and the pilot cancel signal and performs
IC12 2/2 selection and pilot cancel inversion inversion amplification.
1 . adder REC CAL ON : inversion-amplifies the REC CAL signal,
Pin @ : Stereo with auto quieting control pin at less than 1.0V. Mono with pin at
more than 1.8V.
Pin © : 38kHz square wave output -
|C13 3BkHz subcarrier generating MPX IC Pin ® : Stereo indicator drive
Pin ® : Pilot cancel signal (triangle wave) output
Pins @ - @ :PLL loop filter
Pin @ : vco
Multiplies the composite signal and the 38kHz subcarrier. The respective I/o pins are
at current mode.
lC14~17 SUB demodulation linear multiplier Pin (D : 38kHz input
Pin Qt) : Output
Pin . : Composite signal input
IC18 1/2 SUB signal inversion Inverts the Fich SUB signal.