Teac MV1421, Руководство по обслуживанию

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43 PH I-1 FILTER The loop filter connected to pin 43 is suitable for various signal conditions
as strong/w eak and VC R signal.
This is achieved by sw itching of the loopfilter tim e constant by changing
the PH I-1 output current.
Via IIC bus FO A/B,different tim e constants can be chosen,including an
autom atic m ode w hich gives optim al perform ance under varing conditions.
44 G R O U N D To this pin are connected the IC -substrate and horizontal output.
45 EAST-W EST D R IVE not used.
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47 VER T. D R IVE+
VERT D R IVE- The vertical drive has a current output.The output is balanced w hich ensures a
good com m on m ode behavior w ith tem perature and m akes the
output signal less sensitive for disturbances.
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49 IF IN PU T The PLL freq. range is 32-60M H z w ith corresponding V C O freq. 64-120M H z.
The IF input im pedance is 2 in parallel w ith 3pF and m atches the required load
for com m only used saw filters.
A D C coupling is allow ed, so no series capacitors betw een saw filter
and IF input are necessary.
50 EH T/O VERVO LTAG E
PR O TEC T IN PU T not used
51 VER TTIC AL SAW -
TO O TH C APAC ITO R This pin requires a capacitor to ground of 100nF +/-5% .
The optim al saw tooth am plitude is 3.5V and is determ ined by the external
capacitor and charge current.
The saw tooth bottom -level is 2V.
52 R EFER EN C E C U R -
R EN T IN PU T This pin requires a resistor to ground.
The optim al reference current is 100 .w hich is determ ined by this resistor.
53 AG C D EC O U PLIN G
C APAC ITO R
The AG C capacitor value is 2.2 and has been defined for an optim al
com prom ise betw een AG C speed and tilt for all A G C m odes(+/-m odulation)
54 TU N ER AG C O U TPU T This output is used to control(reduce) the tuner gain for strong R F signals.
The tuner AG C is an open collector output w hich is acting as a variable current
source to ground.
55 AU D IO D EEM PH ASIS O nly a capacitor has to be connected to this pin that defines the deem phasis tim e
constant. The signal is internally connected through to the Audio sw itch.
The capacitor can be calculated as follow s.
56 SO U N D D EC O U PLIN G
This pin requires a capacitor of 10 connected to ground.
The pin acts as a low pass filter needed for the D C feedback loop.
N O N A M E D E S CR IPTIO N