Genius 1993, ISO XFR-75W, 2093, 1493, 2793, 3693, 1793 manual Power SUPPLY, Trouble Shooting Tips

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POWER SUPPLY
POWER SUPPLY

POWER SUPPLY, TROUBLE SHOOTING TIPS.

SAFETY FIRST; Use only one hand when working on a powered up monitor to avoid electrical shock.

Always wear safety glasses.

Many of the failures that cause burnt components and boards are eliminated by the load sensitive switching mode power supply in the CERONIX monitor. This feature can cause problems with servicing the monitor if the proper trouble shooting approach is not used. The equipment setup, shown here, is necessary for efficient trouble shooting of the CERONIX monitors.

Problems that cause the power supply to chirp are:

1.Insufficient V+ line load.

2.Overloaded V+, +24V, or +16V lines.

3.Shorted V+, +24V, or +16V lines.

4.Power supply component failure.

5.Raw DC (V+ to V-) voltage too low.

1. A quick check for the insufficient V+ load is to connect a 2K to 4K ohm 10 watt power resistor from GND to the V+ (cathode of diode 181 ). If the chirping stops, proceed to check the horizontal deflection circuit. First disconnect the board from the AC supply. Then connect 16 volts to the 16V line at the cathode of 169 . Also connect 24 volts to the 24V line at the cathode of diode 168 and to V+ at the cathode of diode 181 on the monitor. Now the complete horizontal and vertical circuits can be checked with the oscilloscope and DVM. The flyback waveform will be about 170Vp-p instead of 900Vp-p which permits checking even the H. output transistor, collector, waveform.

2. For the overloaded supply line problems, the monitor power supply can be made to run continuously by connecting the external power supply to the 17V line. To accomplish this, connect the external supply 0V clip lead to V- (resistor 137 lead by the power transformer) and +20V clip lead to the monitor power supply +17V line (cathode of diode 141 ). Sometimes the monitor will operate normally in this mode, in which case, watch for smoke and after a few minutes of operation disconnect the power connections and carefully feel around the conductor side of the board for hot spots. Overload conditions will not harm the power supply unless there is a problem in the power supply. If the power supply is suspect, read the

TEST section on this page. Next check the DC voltage of each of the power supply outputs. The overloaded line will have a lower than normal voltage reading. The defective component can be located by measuring the voltage drop along the trace of this line.

3. If the V+ crowbar zener 181 is shorted, a fault exists in the power supply which permitted the V+ line to exceed +160V. First replace the zener.

Never operate the monitor without the crowbar zener installed. Then read the

TEST section on this page. Shorts on the V+, 24V, and 16V lines other than the crowbar zener are not likely to be connected to the power supply even though the power supply chirps. By operating the power supply with the +20V external power supply many of these problems can be found using the same procedure as are used in trouble shooting monitors with linear power supplies.

4. The power supply may chirp if:

The transformer core is broken or a winding is shorted.

The .33 ohm current sensing resistor value is too high.

The +17V line is open. (goes away when external. PS is used)

5.There is a line voltage range of about 60% to 70% AC line voltage where a correctly operating monitor will chirp.

POWER SUPPLY TEST

To verify that the power supply is working correctly, connect the 17V line, as indicated in section 2 on this page. Also connect the oscilloscope GND to V- and the oscilloscope probe to

the FET drive (anode of diode 116 ). There should be a waveform at this point. If there is no FET

drive waveform, check the voltages and waveforms on the C5184 pins and compare them to the voltages and waveforms on the schematic. Connect the AC power cord with the AC voltage, from the variable transformer turned down to 0 volts. TAKE CARE NOT TO TOUCH THE OSCILLOSCOPE AND MONITOR CHASSIS DURING THIS TEST, SINCE THE VOLTAGE DIFFERENCE CAN BE AS HIGH AS 400 VOLTS. Connect the DVM to GND and V+. Slowly increase the AC line voltage and observe the power supply response. Do not exceed +145V on V+. If the monitor runs normally, a fault may still exist

in the power supply +17V line circuit.

Note; if

the crowbar zener is shorted and the FET is

internally shorted, the C5184 IC

 

 

should also

115

 

be replaced.

 

 

 

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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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