VIDEO INTERFACE CIRCUIT, FUNCTION, DESCRIPTION (+ & - Analog).

The video interface circuit is a general purpose RGB type input circuit. This circuit connects the external video signal to the video amplifiers. It can accept, DC or AC coupled positive going analog, negative going analog, and 4 line TTL.

The particular mode of operation is selected by inserting jumpers, different value components, and solder bridges. The Production Assembly Drawings (PADs) are given in the appendix which describe the component differences.

SIMPLIFIED VIDEO INTERFACE CIRCUIT:

Black Level (5.6V)

1. NEGATIVE GOING ANALOG MODE.

Saturated Color (1V)

 

+12V

RED channel shown

16

VIDEO

 

 

 

 

7.5V BIAS LINE

 

 

 

 

AMPS

 

3.5V

 

 

 

 

 

 

 

 

 

 

 

 

 

Blue channel only

6

 

 

RED

 

 

 

 

 

 

 

 

271

 

 

200

3.6K

MG 12

MASTER

VIDEO

 

 

 

 

 

 

6.3V

 

 

 

 

 

GAIN&

INPUT

301Ω

 

 

C5346

 

 

 

 

340Ω

2

 

 

 

BLANKING

 

 

 

 

 

 

 

 

 

 

278

236

3

 

241

 

 

 

4.7K

 

 

-Analog Black Level

(-A BL)

 

 

 

+12V

 

 

 

 

 

 

 

239

 

 

 

 

 

 

 

 

 

 

G

In the negative analog mode, the video signal has a black level (5.6V) which is the -A BL voltage. The saturated color is the lowest input voltage (.9V-1.1V). The current amplitude to the video amplifiers is defined by resistors 278 & 236 and the master gain voltage.

For the blue channel only, 15% of the output current is subtracted by resistor 239 .

Signal sources with 8 bit drivers, that use 2 bits for the blue channel use this 15% offset.

To prevent input line ringing from exceeding the saturated color voltage limit, a clamp diode

271has been added.

 

Saturated Color (.70V)

 

 

 

 

 

 

 

2. POSITIVE GOING ANALOG MODE.

 

 

 

Black Level (0V)

+12V

RED channel shown

16

VIDEO

7.5V BIAS LINE

 

 

 

 

 

 

AMPS

 

15.8K

11

 

 

 

 

 

 

 

 

 

261

+ANALOG ENABLE

 

 

 

 

RED

 

 

 

 

 

270

15KHz

200Ω

3.6K

MG 12

MASTER

 

VIDEO

75

31KHz .44V

 

 

 

GAIN &

INPUT

278

2

 

 

 

BLANKING

 

 

 

 

 

 

 

C5346

 

 

 

 

 

0-11V or 12V

241

 

 

 

 

 

 

15.8K

 

 

 

 

 

 

 

223

1

 

 

 

 

 

75Ω

 

The black level voltage is set by resistor

 

75.0Ω

J

 

288

226

0Ω

divider 223 &

226 to compensate for the

 

 

 

 

bias current voltage drop. An optional,

 

 

 

 

variable black level, is accomplished with the

In the positive analog mode, a bias current of

black level adjustment pot.

 

.6mA flows to the input pin 2. This current is

The input termination resistor 288

set by resistor

261 at the +Analog Enable

reduces video line ringing and produces a

input pin 11. The .6mA produces a voltage,

dark screen when the video input connector

across the parallel resistance of the game and

is disconnected.

 

 

 

288 plus resistor 278 , at pin 2. If the

The normal saturated color is set at .70

external source resistance is 75 ohms, the black

volts. Higher saturated color levels can be

level voltage at pin 2 is .18V for 15KHz and

accommodated with resistor or gain changes.

.07V for the 31KHz.

 

 

 

 

 

64

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Genius ISO XFR-75W, 2093, 1493, 2793, 3693, 1793, 1993, ISO XFR-100W Video Interface CIRCUIT, FUNCTION, Description + & Analog

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.

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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.