Genius 2093 User Manual
HORIZONTAL DEFLECTION CIRCUIT DESCRIPTION.
3,300pF-38KHz
12
2.7K
1uF
+
-.2VDC
1.5Vpp 04,E6
Hs
7.3-8.7V
4Vpp 02,D6
Hs
7.3-8.7V
4Vpp 03,D6
Vs
3-4VDC
1.4Vpp 05,E6
Hs
2.4-3.4VDC
06,E6
0Vpp
1
6
4
5
2
3
GND
1
18
10K
1uF
+
45K
8.8K
22K
12K
0
Ω
202
I2
I3
I12
I7
344
347
I6
GND
6,10
9
25K
I5
350
351
2
7
8
6.8K
I13
BIAS
MULTIPLIER
Horizontal
SYNC INPUT
POSITION
O/S
SYNC O/S
SAW TOOTH
GENERATOR
TR .
PICTURE
DELAYED
I4
1N4007
333
11
330pF
NEG.
Hs
17
I
PRA
416
484
20K
Horizontal
Position
RC7
comp.
+
-
11
5.4-6VDC
11, E5
348
12-18V
DC
33Vpp 27,E7
Hs
200
Ω
2W
337
340
GND
342
1N4007
2SC4159E
2.2K.5W
341
+24V
338
100uF
+
220uF
334
RC4
Horizontal
Sync
7.3VDC
5.5Vpp 01,D6
Hs
1,000pF-15KHz
330pF-31KHz
330pF-38KHz
330pF-38KHz
+12V Supply
0VDC
56Vpp 62,D6
Hs
+24V to 27V Supply
Remote
Control
PCB
Control
PCB
6,800pF-15KHz
3,300pF-31KHz
3,300pF-31KHz
3.92K
418
3.92K
417
352
56pF
I1
1.8K
3
The picture position O/S clamps timing capacitor
351
to 8.2 volts until horizontal sync triggers this O/S.
The voltage on the timing capacitor drops at a rate set
by the horizontal position control
by the horizontal position control
484
and resistor
I 4
. When the voltage, at pin 2, drops below 4 volts
the delayed sync O/S is triggered and capacitor
351
is
reset to its clamped voltage. The delayed sync O/S
functions the same as the picture position O/S with the
exception that it is not adjustable.
functions the same as the picture position O/S with the
exception that it is not adjustable.
During the active part of the delayed sync pulse,
the multiplier gates current to capacitor
the multiplier gates current to capacitor
346
which
is dependent on the sawtooth voltage at the
delayed sync pulse time. Capacitor
delayed sync pulse time. Capacitor
347
sets the
"0" voltage for the multiplier which is the average
value of the sawtooth waveform.
value of the sawtooth waveform.
The flyback pulse, connected to pin 4 through
resistor
resistor
I6
, starts the negative slope of the saw
tooth generator. When the sawtooth wave, which is
produced by a current to capacitor
produced by a current to capacitor
348
, drops to 3
volts, the sawtooth generator switches back to the
positive slope part of the wave till the next FBP.
positive slope part of the wave till the next FBP.
All of these functions except for the picture
position adjustment are accomplished by the
phase locked loop. Delaying the horizontal
sync with an adjustable timer produces the
picture position adjustment.
position adjustment are accomplished by the
phase locked loop. Delaying the horizontal
sync with an adjustable timer produces the
picture position adjustment.
The functions of the horizontal control circuits are:
1. To provide the horizontal output circuit
with a stable frequency with or without
incoming horizontal sync.
1. To provide the horizontal output circuit
with a stable frequency with or without
incoming horizontal sync.
2. To be able to adjust the picture position,
horizontally, with respect to the raster.
horizontally, with respect to the raster.
3. To operate stability through periods of
missing horizontal sync pulses.
missing horizontal sync pulses.
4. To keep the picture from drifting within
the operating temperature range.
the operating temperature range.
The horizontal sync input circuit (pin 1) will
trigger the picture position one-shot (O/S) on
either the rising edge, or the falling edge, of the
horizontal sync pulse. To accomplish the edge
triggering, the sync pulse is differentiated by
capacitor
trigger the picture position one-shot (O/S) on
either the rising edge, or the falling edge, of the
horizontal sync pulse. To accomplish the edge
triggering, the sync pulse is differentiated by
capacitor
352
into two short pulses, one for the
rising edge and one for the falling edge of the
sync pulse. Which edge is the trigger depends
on the bias voltage at pin 1. For positive edge
triggering, the bias voltage is set to 7.8 volts by
resistors
sync pulse. Which edge is the trigger depends
on the bias voltage at pin 1. For positive edge
triggering, the bias voltage is set to 7.8 volts by
resistors
I2
and
I3
. For negative edge
triggering, the bias voltage is set to 4.1V by
connecting
connecting
I 12
via the solder connection
IA
.
If the delayed sync pulse occurs when the
sawtooth is at a low voltage part of its cycle,
capacitor
sawtooth is at a low voltage part of its cycle,
capacitor
346
discharges and the oscillator
frequency lowers. If the delayed sync pulse occurs
at the top part of the sawtooth wave no current
flows to capacitor
at the top part of the sawtooth wave no current
flows to capacitor
346
. This action, phase locks
the horizontal oscillator to the incoming sync
pulses.
pulses.
I
12
352
I
2
I
3
348
346
I
6
351
484
I
4
346
347
351
346
IA
IA
82