JVC DR-E34BK Service Manual page 20

DR-E34BK
DR-E34LBK
Me 1c105:LA3401 (FM MPX Detector)
1. The main function descriptions
(1) Detect the FM Multiplex Signal (Stereo signal ).
(2) When the FM Signal is Stereo Modulation, it will output the signal for indicator.
(3) AM/FM Audio Amplifier.
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2. Top View & Block Diagram TissTEREG | I Lofft
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PLL Pilot Pilot Mute
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Reactance
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I v4 Decoder Muting Control I
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FM AM Selection
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FM AM Change i P |
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AM in' FM in Pilot Sepa. Lout Post Amp.in. Rout Vcc FM/AM Mute
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1-20 (No. 20162)
Muting signal input.
hae While this terminal going "H%, the VCO stop.
PLL input.
Output of MPX pilot signal (Connected to Pin18).
Separation adjustment.
Switch-over the FM/AM input. "H" : AM, "L° > FM
"H" : Mute on, "L" : Mute off.
he muting time after power on is controlled by the connected capacitor.