Genius 1993, ISO XFR-75W, 2093, 1493, 2793, 3693 Vertical and Horizontal Sync Circuit Description

Page 62

VERTICAL AND HORIZONTAL SYNC CIRCUIT DESCRIPTION.

Composite

 

Vertical Sync

{ Horizontal Sync

Sync

 

 

 

Sync Interface 2 Comparators

For Interlaced Vertical Sync.

+

 

 

 

 

 

Vertical Sync To Horizontal Cycle Synchronization and Composite Sync Decoder

To LA7851 pin 19

To LA7851 pin 1

Composite sync or separate vertical and horizontal sync are buffered by two comparators in the sync interface circuit. A vertical sync synchronization circuit is used to insure a stable raster and functions as a sync separator.

The synchronization circuit is bypassed, for interlaced vertical sync, because this circuit rejects the half horizontal line time variation used to generate the interlaced vertical raster.

 

 

 

 

 

Vertical Sync

 

Horizontal Sync

 

FBP

 

 

 

 

 

 

 

 

 

 

+12V

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7.15K

 

 

+

9

15.8K

68.1K

15.8K

 

 

 

 

 

 

 

 

366

7.15K

14

1/4

 

353

354

360

 

 

 

 

 

 

 

 

 

364

 

LM339

8

 

2.1-2.4VDC Hs

 

 

0Ω

 

Interlace (15KHz)

 

355

 

 

 

 

 

 

 

1K

4.6Vpp 58,D6

 

 

364

 

10uF

 

 

 

 

 

 

1.5-2VDC

59,D6

 

 

 

 

+

 

 

 

 

 

 

357

 

 

 

 

1K

259

1.8K

 

0Ω

 

 

+

11

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

13

 

 

 

 

 

246

 

47nF

257

 

318

 

1/4

 

 

 

 

 

 

 

 

 

LM339

 

 

 

 

 

 

 

 

254

 

 

 

 

 

 

10

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

355

 

 

 

 

 

 

 

 

+12V

 

 

6.8K

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3.92K

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

358

 

 

 

 

 

 

22K

 

 

321

 

 

 

356

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

323

 

 

6.8K

 

200K

.05VDC

Vs,Hs

 

 

 

 

1.8K

 

 

4

 

 

3

322

 

246

 

 

 

 

 

 

 

 

 

7V pp 60,C5

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

325

 

270Ω

 

1/4

2

 

 

PN2222

 

 

 

 

 

 

 

 

5

LM339

 

 

 

 

 

 

 

 

GND 0Ω

 

326

+

 

355

 

 

 

 

 

 

 

 

 

 

6

 

 

 

 

 

 

 

 

 

 

 

 

328

 

 

 

 

 

 

 

255

 

 

 

 

 

 

 

270Ω

 

 

 

1

 

 

 

 

 

 

 

 

 

 

 

 

1/4

 

 

 

 

 

 

 

 

 

1.8K

 

330

 

LM339

 

 

100K

PN2222

 

 

 

 

 

 

7 +

 

355

 

 

257

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

331

 

.14-.16V

 

12

 

.047uF

200K

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Hs

Vs

 

 

270Ω

 

 

 

318

256

 

254

 

 

Horizontal

 

 

327

 

 

 

33K

 

 

VC

VC Vertical

 

 

 

 

 

 

 

 

 

 

Sync

1

2 Sync

 

GND

 

 

 

 

 

GND

 

247

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The sync interface comparators are biased to .15 volts, by resistors 323 & 327 , to permit receiving low level sync signals such as RS170. For low level composite sync, the vertical and horizontal lines are tied together and jumper 328 is left off. For normal amplitude sync, (greater than 2.3 volts) resistors 325 & 326 form an attenuator to protect the sync interface comparators and normalize the sync amplitude. This combination also reduces noise sensitivity since the sync voltage amplitude is low at the comparator input which slows the comparator response and acts as a low pass filter.

For the interlaced sync case, the pullup resistor 321 is left off and the voltage divider resistors 246 and 257 act as the pullup. Also the vertical sync synchronization comparators are disabled by changing the input resistors to bias the comparators in the high output state and resistor 366 is left off. Capacitor 254 acts as a sync separator for composite interlaced sync. Capacitor 259 and jumper 364 are used to couple the composite sync to the LA7851 vertical sync input pin 19.

The vertical sync synchronization window comparator generates a pulse, a little after the midpoint of each horizontal cycle. This pulse is shorted to GND by transistors 255 except when vertical sync is active. The two transistor circuit permits using either positive or negative pulses for vertical sync.

Capacitor

318

couples the vertical sync pulses to

transistors

 

 

 

&

 

. When no sync pulse is present,

 

254

255

transistor

 

 

 

is

turned

on by resistor

 

 

. For a

255

246

negative vertical

 

sync pulse, transistor

 

 

is turned off

 

 

255

by the negative pulse applied to resistor

 

 

 

 

and the

 

257

 

window comparator pulse is allowed to be the vertical sync pulse. For positive vertical sync pulse, transistor 254 is turned on by resistor 247 & 256 , which shorts the base of transistor 255 to GND also allowing the window comparator pulse to act as the sync pulse.

A sawtooth waveform is produced on integrating capacitor 358 by applying the flyback pulse to resistors

360& 357 . This sawtooth waveform is connected to two

comparators which are biased by resistors 353 ,

356 , 354 , & 360 such that both comparator outputs are high between 1.8 volts to 2.3 volts. This circuit would produce a pulse on both the positive and negative slope parts of the sawtooth waveform. Resistor 357 eliminates the output pulse on the negative slope by introducing part of the flyback pulse to pin 8 which keeps the comparator from going high at this time. Resistors 364 & 366 act as a pullup for the window comparator and apply a 6 volt bias to the vertical sync input, LA7851 pin 19. At 6 volts, the vertical sync input is inactive. It becomes active only when the window comparator output and the ± sync transistors are all high.

78

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Contents N U a L R V I C E Year Limited Warranty About this Manual Table of Contents Iii Monitor Simplified Block Diagram Installation Instructions For The XX93 Monitors Instructions d´installation des écrans Installationsanweisungen für die XX93 Monitore Ceronix XX93 Monitor Electrical Specification High input voltage 20V Low input voltage 30V 80V Ceronix 189 in2 1,224 cm2 Page Page Page Page Control Description Circuit XX93 Monitor Block Diagram CRT C D E F G H I J Ceronix Model 1493-VGA, 1493-SVGA CPT1536 Ceronix KLM RED FIL RAY Note Produktsicherheit Anmerkung Ceronix XX93 Monitor Part List MM7 LL6 II7 FF9 FF3 BB6 DD8 DD9 HH2 Jumper, Normal Vertical OO6 15KHz, FBT Hitachi BW02651 PP4 RR0 VV2 RR7 CRT T U Video Interface CIRCUIT, FUNCTION, Description + & Analog CRT TC12 Controls XRC5346A + H. Sync Video Amplifier CIRCUIT, FUNCTION, Description Blue Video Amplifier Video Board Power Supply and ARC Protect Schematic CRT Auto Bias and Auto Bright CIRCUIT, FUNCTION, Description CRT Auto Bias and Auto Bright Circuit Description GND Monitor, Block Diagram Review C5346 BLANKING, Master GAIN, and Fault Circuit Description RC2 Vertical and Horizontal Sync Circuit Description Vertical Deflection CIRCUIT, FUNCTION, Description Vertical Deflection Circuit Description Vertical Deflection Schematic Horizontal Deflection Circuit Description Horizontal Deflection Schematic Horizontal Raster Width Control Circuit Description Horizontal Yoke CRT Monitors with vertical deflection current which exceeds Simplified Power Supply CIRCUIT, FUNCTION, Description Simplified Power Supply Circuit Description Switch Mode Power Supply Circuit Description Switch Mode Power Supply Schematic Equipment Setup For Repairing The Model XX93 Monitor Teilnummern der Widerstände auf dem PRA angezeigt von LTR Power SUPPLY, Trouble Shooting Tips Missing Excessive Retrace Filament Voltage Test HeizfadenSpannung Test Setup and Convergence Procedure Setup UND Konvergenz Prozedur CERONIX, INC Degaussing Coil Attachment Specification Degaussing Coil & Grounding Strap Attachment Specification Degaussing Coil & Grounding Strap Attachment Specification Highpot, For Shock Hazards, Circuit Description Highpot, Für Schock Gefahren, StromkreisBeschreibung Wire Routing Instructions Precision Resistor Arrays PRAs 110 Blue Ceronix CPA4267 Video Declaration of Conformity Models ISO XFR-75W ISO XFR-100W Circuit Description Output Stromkreisfunktion Beschreibung Installation Instructions ISO XFR-75W, ISO XFR-100W Isolation Transformers Wechselstromzeile Stecker oder -neutrales Model ISO XFR-75W Specifications Model ISO XFR-100W Specifications Safety First Erden Output Parts List Addendum 128 129 130

2093, 1493, ISO XFR-75W, 3693, 2793 specifications

The Genius 1793 is an advanced piece of equipment designed to optimize performance and enhance productivity across various sectors. Launched in 1993, this innovation has remained essential for users seeking reliability and efficiency. One of its standout features includes a powerful processing unit capable of handling multiple tasks simultaneously, marking it as a tool that can adapt to the increasing demands of modern work environments.

Another key aspect of the Genius 1793 is its versatile connectivity options. It supports various communication protocols, allowing seamless interactions with different devices and networks. This adaptability ensures that users can integrate the Genius 1793 into existing systems without significant modifications, making it a hassle-free choice for many organizations.

ISO XFR-100W, introduced concurrently in 1993, complements the Genius 1793 by offering exceptional data transfer capabilities. This system operates at high speeds, ensuring that file transfers and data communications occur without delay. Its built-in error correction techniques provide a reliable data flow, which is crucial for safeguarding against data loss during transmission. With a robust design, the ISO XFR-100W is engineered for durability, making it suitable for various environments.

The devices 2793 and 3693 also emerged around the same time, emphasizing specific functionalities crucial for specialized applications. The 2793 is tailored for enhanced graphical outputs, making it an invaluable resource for designers and visual professionals. Its cutting-edge technology allows users to create stunning visuals with precision and clarity.

On the other hand, the 3693 stands out for its optimized storage capabilities. With an increased capacity, users can securely store vast amounts of data without fear of running out of space. Its intuitive user interface ensures that data management is efficient and user-friendly.

Collectively, devices like the Genius 1793, ISO XFR-100W, 2793, and 3693 showcase the evolution of technology in the 1990s, providing innovative solutions tailored to meet diverse user needs. Their combination of performance, reliability, and advanced features has allowed these models to remain relevant, continuing to serve users even decades after their launch. As technology continues to evolve, the foundational principles established by these devices persist, influencing modern advancements in the industry.
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