001 001 012 001 001 032 055 007 001 001 001 079 014 041 004 023 009 130 268 001 061 009 347

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...

2

BLANKING, MASTER GAIN, AND FAULT CIRCUIT DESCRIPTION. The master gain control 485 is connected to the video gain line through a 1K resistor 062 . The voltage range of the video gain line is programmable via resistors I 064 I, 076 I and solder bridges at (s , t) , & . The solder bridges may connect resistors 244 , r245 , 258 , and 260 to the video gain line. This arrangement permits a variety of input signals and picture tubes to be used with the same monitor PCB. Horizontal blanking ( H b )...

2 Positive Going Analog Mode

In the positive analog mode, a bias current of .6mA flows to the input pin 2. This current is set by resistor I 261 I at the +Analog Enable input pin 11. The .6mA produces a voltage, across the parallel resistance of the game and I 288 I plus resistor 1278 I , at pin 2. If the external source resistance is 75 ohms, the black level voltage at pin 2 is .18V for 15KHz and .07 V for the 31KHz. The black level voltage is set by resistor divider I 223I & I 226 I to compensate for the bias current...

2093

Five Controls are located on a separate PCB for easy access. H SIZE--------------Horizontal raster size V SIZE---------------Vertical raster size V RAS. POS.-----Vertical raster position H POS-------Horizontal picture position M GAIN---------------------Master gain The board Controls are located on the main PCB Focus and G2 on the FBT. Optional board Controls are pincushion, video black level, and horizontal hold control. 5. Image Horizontal linearity Vertical linearity Pincushion

254

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 315 & 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...

3

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. 2. To be able to adjust the picture position, horizontally, with respect to the raster. 3. To operate stability through periods of missing horizontal sync pulses. 4. To keep the picture from drifting within the operating temperature range. All of these functions except for the picture position adjustment are accomplished by the phase...

5

In the + analog AC coupled mode, the video black level is set by a clamp circuit which is active during the first part of horizontal sync. For this circuit to work properly, the incoming video must be at the black level voltage when horizontal sync starts and remain blanked for at least 4.5uS. The clamp circuit is dependent on the polarity of incoming horizontal sync. For separate horizontal sync, the sync polarity should be positive. For composite sync, and positive going horizontal sync...

About This Manual

This manual is specifically written to aid the service technician, repairing CERONIX Models 1493, 1793, 1993, 2093, 2793, and 3693 color monitors. To understand how the Monitor works, it is best to know what each circuit does and how each circuit relates to the other circuits. The Block Diagram is presented in a simplified view and a comprehensive view to accomplish the goal of understanding the whole unit. Once the general picture is clear, the complexity of each circuit will be easier to...

Attach The Grounding Strap First

With the degaussing coil leads centered on the bottom of the CRT, FORM THE COIL to avoid the remote control board. INSTALL A WIRE TIE through INSTALL A WIRE TIE through the top hole in the left CRT ear. the top hole in the right CRT ear. INSTALL WIRE TIES through the bottom hole in the left CRT ear. INSTALL WIRE TIES through the bottom hole, with the grounding strap spring, in the right CRT ear. Degaussing Coil & Grounding Strap Attachment Specification. For The Model 1793, 1993, 2093 Video...

Blue Input

For DC coupled positive analog video signals, the signal source black level is 0 volts. The standard saturated color voltages are .7 volt and 1 volt. The RGB video signals and sync are connected to the monitor through the video input connector 292 . Resistors 288 , 286 , & 284 terminate the video lines and load the input such that, when no signal source is connected, the screen is dark. Resistors 278 , 277 , & 276 protect the video interface IC 241 from transients. They also act as load...

Ceronix

13350 New Airport Road Auburn, CA, USA 95602-7419 Fax (530) 888-1065 VIDEO For the following measurements use an oscilloscope. With no load, the black level voltage of the video drive signal is With no load, the saturated color voltage is To simulate the monitor input resistance. With 75Q load on the video drive signal the black level voltage is the saturated color voltage is

Crt Auto Bias And Auto Bright Circuit Description

The beam current feedback circuit uses a PNP video transistor 954 to direct most of the beam current to the auto bias circuit while passing the voltage waveform, from the video amplifiers to the CRT cathodes. Diode I 958 I and capacitor I 956 I insure that no video waveform distortion occurs. An additional benefit of this circuit is that it protects the video amplifiers from the destructive arc energy. Resistors I 948 I and I 955 I divide energy due to CRT arcing, between the video amplifier...

Crt Auto Bias Vertical Sync

The vertical oscillator one shot (LA7851 pin 16) supplies the start timing for the auto bias vertical sync. This signal is conducted to the emitter of 379 by jumper 089 . The base of 379 is connected to the retrace boost pulse by resistor divider 3831 and 384 . Combining these signals in this way produces a collector waveform which has the vertical oscillator one shot timing and is dependent on the retrace boost pulse. For the 15KHz case, transistor 100 inverts the vertical oscillator one shot...

Dynamic Focus Circuit Function And Circuit Description

The dual focus CRTs require a waveform on the 2 focus grid. This voltage waveform is dependent on the position of the beam on the CRT. The lowest voltage part of the waveform is in the center of the screen and the highest voltage part of the waveform is at the corners of the screen. The dual focus CRTs require a waveform on the 2 focus grid. This voltage waveform is dependent on the position of the beam on the CRT. The lowest voltage part of the waveform is in the center of the screen and the...

Equipment setup for trouble shooting the Iso Xfr75W Iso Xfr100W Isolation Transformers

SAFETY FIRST Use only one hand when working on a powered up ISO XFR-75W, ISO XFR-100W to avoid electrical shock. Always wear safety glasses when working on powered up electronic equipment. Note When using this isolation supply for working on monitors, it is important to have some resistance (10MQ or less) to ground. An insulated monitor connected to a insulated power supply may attain a high static voltage. When this voltage discharges through the ISO XFR-75W, ISO XFR-100W control circuit, the...

Fr205 853

L ten Sie zwei kurze bussleitungen zu den Heizfadenanschlu stiften weich. 2. Benutzen Sie schwarzes Band, um die Fotozelle ber der Bohrung im Plastik-CRT-Einfa ung Stecker zu sichern. Vorsicht Seien Sie sicher, die Fotozelle nicht zwischen die zwei Tests zu verschieben. 3. Speichern Sie die Gleichstromspannung, die von der Fotozelle mit dem Monitor ausgegeben wird, der normalerweise l uft. Der Monitor Mu laufen damit 10 Minuten die Heizfadenspannung messen. 4. Drehen Sie weg den Monitor Ab. 5....

Hh8

CERONIX XX93 Monitors MUST USE AN APPROVED ISOLATION TRANSFORMER. The monitor chassis must be connected to earth ground via a common connection in the system which contains the monitor. X-radiation is produced by electrons colliding with the phosphor and shadow mask at the front of the picture tube. The X-radiation emanating from the front of the picture tube is highly reduced due to the shielding affect of the leaded glass face. It is also produced at the anode bulb contact. The X-radiation...

Info

Plugs in main board left side of flyback transformer. Highpot, For Shock Hazards, Circuit Description. For the models 1493,1793, 1993, 2093, 2793, and 3693 video monitors. It is the responsibility of the company which uses the Ceronix monitor in there system to make sure that no shock hazards exist. Below is a description of the highpot test to verify that the monitor is properly connected to an isolation transformer. Once the monitor is installed in the enclosure, the...

Installationsanweisungen fr die XX93 Monitore

Ein 3 Ampere-T Sicherung (f r die degaussing-Str mung) und ein 75 VA Isoliertransformator ist die Minimum-Forderung f r benutzen unseren Monitoren in einem Produkt. 3. Schlie en Sie den Monitor F r Details, Folgen Sie den Installation-Anweisungen, im Gehause an. Vom Lieferanten der Antriebelektronik. 4. Verbinden Sie den Gr ne Gelben Schutzleiter zum Erdung anschlu auf dem Gehause. Dieser Draht ist verbunden zur der Erdung-Schraube auf dem Monitor-Chassis, und wird hinter der...

Isolation Transformers

The ISO XFR-75W -100W MUST be grounded by mounting on a grounded, conductive surface via at least two screws. WARNING Mains power and ground connections must be made before power is applied to the ISO XFR-75W or the ISO XFR-100W Isolation Transformers. WARNING FOR CONTINUED SAFETY, REPLACE SAFETY CRITICAL COMPONENTS ONLY WITH MANUFACTURER'S RECOMMENDED PARTS (REFER TO SERVICE LITERATURE). AVIS POUR MAINTENIR LE DEGRE DE SECURITE DE L'APPAREIL NE REMPLACER LES COMPOSANTS DONT LE FONCTIONNEMENT...

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...

Rc3

376 1N4005 3821 H.+12V The vertical sync comes from the synchronized vertical sync interface circuit for monitors without interlace. For monitors with interlace the vertical sync comes from the sync comparator via a coupling capacitor and bypasses the synchronizing circuit. Pin 19 of the LA7851 is the vertical sync input and will start the next oscillator cycle on either the positive or negative sync pulse. The vertical oscillator capacitor 410 discharges to 4 volts on the leading edge of the...

Simplified Video Amplifier Circuit

The video amplifier drive circuit is built on a ceramic substrate which is a good heat sink. The printed resistors and conductors are small and have precise geometries which output a faithful reproduction of the input signal with good high frequency response and low overshoot. The NE592 is a 120MHz emitter coupled differential amplifier which is connected to a push pull output stage. This output stage has a low bias current of 3mA and a bandwidth of 25MHz. Although at 25MHz, the output stage...

Stromkreisfunktion Beschreibung

Die grundlegende Funktion des XFR75W und des XFR100W ist, die Zeile Energie f r die ben tigenden Monitoren und Lokalisierung Transformator zu lokalisieren. Der Transformator wird entworfen, um einen niedrigen Durchsickernflusswert zu haben, der erlaubt, da er nah an der CRT eingehangen wird. T vollenden den niedrigen Durchsickernflu , hat der Transformator zwei Sets der Prim r- und Sekund rspulen, die an einem ge nderten Ringk rperartkern eingehangen werden. Der ideale Transformator w rde ein...

Tc Z

The high voltage in the CRT, through an arc, can be conducted to any tube socket connection on the video board. To reduce the danger of these arcs causing component failure, a number of arc current paths are provided. The tube socket has integral spark gaps which conduct arc current to the tube ground (aquadag). through dissipation resistor 882 . The clamping voltage of the spark gaps to the cathodes and G1 is about 1.5KV. The peak arc current to the video amplifier outputs is limited by...

Vertical And Horizontal Sync Circuit Description

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 Oscillator

The one shot in the LA7838 clamps the ramp forming capacitor 401 to 5 volts for about half of the vertical retrace time. Capacitor 384 and resistor 402 form the RC circuit for the ramp reset one shot. The ramp capacitor 4 T is charged by current from a current generator with a 6 volt input node at pin 4. The vertical size is adjusted by the vertical size control 82 which is connected to pin 4 via resistors 003 & 375 . The adjustment range is set by resistor 375 and the maximum deflection is...

Vorrichtungen haben zum Lsen von Problemen mit dem 75W und dem 100W Isolierung Transformatoren benutzt

SICHERHEIT ZUERST Um elektrischen Shock zu vermeiden, benutzen Sie nur eine Hand beim Arbeiten auf einem angeschaltenen Transformator 75W oder 100W. Tragen Sie immer Sicherheitsgl ser beim Arbeiten auf angeschaltener elektronischer Ausr stung. Anmerkung Beim Benutzen dieser Isolierung Versorgung von Monitoren dem Bearbeiten zu, ist es wichtig, irgendeinen Widerstand zu haben, (10 Meg.Q oder kleiner) zu erden. Ein Isoliermonitor, der an eine Isolierenergie kann angleschlossen wird eine hohe...

W

A +12V regulator is used to supply current, to all the control circuits in the monitor, with the exception of the power supply. Many of the control circuits are decoupled from the +12 volt line with a resistor or diode to minimize noise from common current loops. The Over Voltage Protect circuit is built into the power supply and monitors the flyback transformer peak pulse voltage. This circuit will turn off the power supply and hold it off if the EHT exceeds its maximum rated value. Since...

Wire Routing Instructions

Attach the protective earth, Fold remote cable to clear green yellow, ground wire. CRT and add wire tie. Rout G2 wire around CRT socket, shorten with loop, and add wire tie. Plug in video board. Fold video flat cable to avoid contacting the metal frame. Secure fold with a wire tie. Shorten focus wire and add wire tie. Finished assembly with the different voltage type wires not touching each other. Make solder connection CA when using these C PRAs for replacement parts on the XX92 product line....

Xy

. Represents the XX93 board part number. The parts list gives the CERONIX PART NUMBER which is indexed to the board part number. Part numbers of the resistors on the PRA indicated by LTR. PRA pin number. To determine which PRA the pin number belongs to, look for the nearest PRA part number on that line. fDC voltages are measured to GND except in the power supply where V- is the reference. Use a DVM for DC measurements.

Circuit Function Description

The basic function of the ISO XFR-75W and ISO XFR-100W is to isolate the line power for monitors requiring an isolation transformer. The transformer is designed to have a low leakage flux value which allows it to be mounted close to the CRT. To accomplish the low leakage flux, the transformer has two sets of primary and secondary coils mounted on a modified toroid type core. The ideal transformer would be a toroid but this type transformer is expensive because it is difficult to wind. A relay...

Horizontal Raster Width Control Circuit Description

The purpose of the horizontal width control is to 1. Provide a convenient means for adjusting the horizontal raster size. 2. Correct pincushion distortion in the vertical axis. 3. Correct horizontal raster distortion caused by periods of high beam current. The horizontal width control circuit is comprised of two main parts The control circuit and the diode modulator (DM). The control circuit combines four signals in the monitor to produce the width control circuit. These signals are 1....

High Pot Tester

The MONITOR is connected to the enclosure ground via the signal cable, monitor support hardware, and the protective earth ground wire. The chassis ground must be connected to earth ground. All the large accessible metal parts are connected to ground. Highpot, F r Schock Gefahren, StromkreisBeschreibung. F r die Modelle 1493,1793,1993,2093,2793, und 3693 videomonitoren. Es ist die Verantwortung der Firma, die den Ceronix Monitor in dort system benutzt, sich zu vergewissern, da kein Schock...

Simplified Power Supply Circuit Description

The FET drive circuit avoids this problem by sensing flyback diode conduction. If the flyback diode conduction is sensed, the low current start mode is selected. This mode turns the FET on, to a current of .1A, for not more than 4uS. If before or during the low current FET on time, the flyback diode breaks free, and the FET drain voltage goes down, the flyback diode voltage comparator will signal the regulator to permit the FET to be turned on for a full power cycle. The cycle after the last...

R

The Horizontal Size Control circuit has four inputs 3. Vertical linear ramp-----------------------, , _. w , , 4. Vertical parabolic V. linear ramp -- The horizontal size control circuit sums the four signals at one node plus the feedback from the diode modulator to drive a switching mode power driver. The output of the power driver is then connected to the diode modulator through an inductor to complete the control loop.

20

6,800pF-15KHz 3,300pF-31KHz 3,300pF-38KHz 6,800pF-15KHz 3,300pF-31KHz 3,300pF-38KHz The voltage on capacitor 346 controls the horizontal oscillator frequency via I 18 I. In the case of missing horizontal sync pulses, the multiplier does not sink current and flywheel capacitor 344 holds the horizontal frequency constant. Resistor I7 permits small rapid changes of the control voltage at pin 7 for locking of the oscillator to horizontal sync. The horizontal oscillator capacitor 345 charges to its...

La7851

In similar manner, the positive half of the vertical current waveform is conducted by transistor 373 diode 405 , and resistors 3721 and 404 . Both transistors 373 and 4H may be connected to pin 4 via solder connection h or they may be connected to inverting transistor 1409 I and resistors I 412 I and I 413 I . The inverting transistor is connected with solder connection I and decreases the vertical size at the top and bottom of the screen. The ramp capacitor 40 is connected to a differential...

Blue

13350 New Airport Road Auburn, California 95602 USA Models 1493-CGA, 1493-VGA, 1493-SVGA. 1793-VGA, 1793-SVGA. 1993-VGA, 1993-SVGA. 2093-CGA, 2093-VGA. 2793-CGA, 2793-VGA. 3693-CGA. Component Isolation Transformer Assembly. Models ISOXFR-75W, IS0XFR-100W. 'National Differences AT, AU, CA, DE, ES, FR, GB, HU, RU, US, ZA.' CAS CAN 60950-00 UL 60950, 3rd Edition IEC 65 85 A1 87 A2 89 A3 92, 5th Edition 'National Differences KR.' I hereby declare that the equipment named above has been tested and...

Ceronix 2793 Service Manual

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

Video Amplifier Circuit Description

The video amplifier's output voltage, with no input signal, is the black level which is the picture tube cut off voltage. This voltage is set, for each of the three video amplifiers, by the auto bias circuit via the bias control line. This black level voltage has a range of 80V to 110V. The voltage swing at the output is 60 volts for a 10 mA current signal from the C5346. For this same 10 mA current signal, the voltage swing at the video amplifier input is 1.5 volts and the input voltage swing...

Vc

In each of the video interface circuit configurations, current from the interface circuit is converted to a voltage at the CRT cathodes. The simplest current path is accomplished bv the negative analog video interface configuration. and there is no video amplifier output. For the red and green channels, a 1 volt change at the video input produces a 15 volt change at the video amplifier output. For the blue channel this change is 18 volts but resistor 265 subtracts the equivalence of .6 volts...

127v

The bias current of the push-pull output stage is set by resistors K14 , K15 , KH , K17 , and diode connected transistor 950 . Transistor 950 is thermally connected to transistor 95T to maintain the same base to emitter voltage drop. Note that resistor K17 adds 11mA to the diode connected transistor 950 . This current is available to drive the base of transistor 951 during periods of high frequency amplification. This high base current is needed because, the beta of transistor HJ is low for...

Iihiiiiiihi

The following waveforms are taken from the 2793-VGA monitor. See waveform 1 for the vertical deflection current. Waveform 2 shows the LA7838 output current. Waveform 3 shows the current supplied by the vertical booster amplifier circuit. These current waveforms describe how the vertical booster circuit reduces the LA7838 output current to a current which is well within the specification of the IC. Vertical yoke drive, voltage waveform. Vertical yoke drive,...

2pl Cpm2013

Plugs in main board left side of flyback transformer. Degaussing Coil amp Grounding Strap Attachment Specification. For The Model 2793 and 3693 Video Monitor. 1. The first item to attach to the picture tube is the grounding strap. Lay the tube face down on a soft surface. Slide the folded over end of the braid over the left top CRT mounting ear. Attach the spring at the other end to the, right side top, slot in the rimband. Pull the bare wire through the bottom slot in the...

Instructions dinstallation des crans XX93

Un fusible fusion lente de 3 amp pour le courant du champ magn tique d'adjustement et un transformateur d'isolation de 75 VA sont le minimum requis pour utiliser nos crans dans un produit. o t ii i j Se r f rer aux instructions d'installation foumies par le fabriquant 3. Installer l cran dans son carter. , , , , ,,, du syst me pour les d tails de montage de l cran dans le carter. 4. Relier le fil de terre vert jaune la prise de terre sur le carter. Ce cable est reli la vis de terre situ e...

Installation Instructions For The XX93 Monitors

A 3 amp slow blow fuse for the degaussing current and a 75 VA isolation transformer are the minimum requirements for using our monitor in a product. 3. Install the monitor in the enclosure. Refer to the installation instructions supplied by the system manufacturer for details of mounting the monitor in the enclosure. 4. Connect the green yellow ground wire to the earth ground connection on the enclosure. This wire is connected to the ground screw, located on the monitor chassis behind the...

Table Of Contents

Block Diagram Crt Monitor

Video Amplifier Circuit, Function, Video Amplifier Circuit Description and Video Board Power Supply and Arc Protect CRT Auto Bias and Auto Bright Circuit, Function, CRT Auto Bias, Auto Bright, and Vertical Sync Delay Circuit Description 72 CRT Auto Bias and Auto Bright Monitor, Block Diagram Blanking, Master Gain, and Fault Circuit, Function, Blanking, Master Gain, and Fault Circuit Blanking, Master Gain, Beam Limiter, and Fault Vertical and Horizontal Sync Circuit Vertical Deflection Circuit...

2 Year Limited Warranty

This product is warranted by CERONIX to be free of defects in material and workmanship for a period of two years from the date of purchase. All parts and labor are free of charge during the warranty period. This warranty does not cover mechanical breakage due to physical abuse. It is the customer's responsibility for shipping the defective unit to and from CERONIX or one of the authorized service centers for repair. Please attach a note describing the problem. CERONIX Inc. 13350 New Airport...