Panasonic KX-G8300 Service Manual And Technical Manual page 48

'KX-G8300
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IFsignal
Fig. 47
Bandwidth Selector Circuit and Post IF Amplifier
The IF bandwidth of the IF amplifier is switched between approximately 8 MHz and 3 MHz, depending on
whether the long or short pulse mode has been selected. In short pulse mode, the output signal from IF
amplifier [C601 is connected to the next stage post IF amplifier via IFT (T602) and diode D602. The
bandwidth on short pulse mode is set to approximately 8 MHz.
In the long pulse mode, transistor Q604 is driven into conduction by the PW signal from the display unit,
the bandpass filter consisting of Q603 and T603 is overridden, and the bandwidth of the IF amplifier is set
to 3 MHz.
The bandwidth selector circuit output is sent to the next stage post amplifier section (IC602) where it is
amplified by about 35 dB, after which it is supplied to the detector circuit.
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Fig. 48
Detector Circuit (1C603, Q605)
The IF signal output from the post amplifier is supplied to IC603 where it is amplified by about 10 dB, it is
detected by the detector circuit inside IC603 and converted into a video signal. The IC603 video output is
sent to the display unit via buffer circuit Q605.