SHARP ELECTRONICS (UK) LIMITED CA1/CA10 Chassis Course Notes
Contents Introduction to the CA10 Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 1 CA10 Receiver Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2 CA10 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 3 Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tuner and IF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tuner and IF processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic frequency control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tuning features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . IF signals . . . . . . . . . . . . . . . . . . . . . . . .
Vertical Driver Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 56 Vertical Output Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 57 Frame Scanning Coils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 58 CA1 Line Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figures Figure 1 : Overall Block Diagram of the CA10 Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 3 Figure 2 : Mains Filter and Indicator Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 4 Figure 3 : Mains Rectifier Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 5 Figure 4 : Power Supply Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CA10 Course Notes Introduction to the CA10 Chassis As with the last Sharp colour television chassis ( CS ) the new CA10 design incorporates the latest technology from Japan and Spain where the receivers are designed and manufactured at the production plant in Barcelona. Once again the reliable switched mode power supply, based around a field effect transistor, is used to provide power for the operation of the set.
CA10 Course Notes CA10 Receiver Specifications The table below lists all of the current range ( as of January 1998 ) of Sharp television receivers utilising the CA10 chassis. Note that the receivers featuring a sub-woofer will have an extra drive PWB fitted and the SRS models will have the SRS sound processing sub PWB fitted.
CA10 Course Notes CA10 Block Diagram To give an overview of the CA10 Chassis, the block diagram shown below represents a pictorial view of the receiver and its individual components.
CA10 Course Notes This self running switched mode power supply is based around a single field effect transistor, Q701 and generates the following supplies for use in various parts of the receiver. Note that other supplies are generated by the line stage and are covered in the Line Stage section of these notes.
CA10 Course Notes Figure 3 : Mains Rectifier Circuit D701, D702, D703 and D704 full wave rectify the incoming mains and this rectified voltage is smoothed by C705. The resultant 320VDC is now fed to the switched mode power supply. D705 is used to limit possible damage caused to the bridge rectifier from internally generated noise that could come close to the PIV of the diodes. Note that in some versions of the CA10 chassis, this diode is not fitted.
CA10 Course Notes Figure 4 : Power Supply Waveforms Page 6 Sharp Electronics (UK) Limited CE Technical Support Group
CA10 Course Notes Figure 5 : CA10 Power Supply - Non-isolated Side Sharp Electronics (UK) Limited CE Technical Support Group Page 7
CA10 Course Notes Figure 6 : Power Supply Regulation Circuit - Secondary Side Voltage regulation Voltage regulation is provided by the feed back through the opto coupler, IC705. The 150 volt line is used as the controlling source and a reference is provided from the +13V supply. Protection is also incorporated via the +7V supply for faults that may occur on either of the five volt supplies ( STB5V and +5V ).
CA10 Course Notes will allow Q704 to conduct more and the LED will become brighter. As the LED becomes brighter, the transistor within IC705 will conduct more allowing C713 to charge faster and thus turning on Q703 quicker. Q703 will discharge Q714 and turn Q701 off, making the on time of Q701 shorter. The emf will decrease and the voltages induced in the secondary windings of T701 will also decrease.
CA10 Course Notes Over current control Over current control is performed by monitoring the amount of current passing though the chopper output transistor drain earth return resistor, R716. This resistor is an extremely low value, 0.47R, and Ohms Law dictates that the current flowing through it must be proportional to the voltage across it. If the base voltage required to turn on Q702 is +0.65V then the voltage across R716 to ‘trip’ the circuit would have to be approximately 1.
CA10 Course Notes When the magnetic field within T701 collapses, the back emf generated across the primary winding causes large voltage spikes to appear across pins 12 and 17. If these spikes are not suppressed, then damage will occur to the primary side of the power supply. To prevent this from happening a snubber circuit, consisting of D711, R715 and C710 is used. Thus when pin 12 becomes positive with respect to pin 17, D711 will conduct and current will flow through R715.
CA10 Course Notes Primary Processor As described previously, to control the operation of the set in the standby mode a primary processor is utilised. The circuit diagram of this part of the circuit is shown below. Figure 10 : Primary Side Microprocessor The two transistors Q708 and Q709 comprise a monostable, which is triggered from the mains input at double frequency, i.e. 100Hz. The square wave signal on pin 8 ( PB6 ) is used to control the on timer.
CA10 Course Notes System Control Resets and oscillators When the power supply starts up the program within the main microprocessor needs to be reset. This is achieved with the use of the circuit shown below. Figure 11 : Reset Operation Circuit When the STB5V supply has reached its correct level, the output from IC102 changes from a low to a high level to reset IC101 on pin 67 ( RSTIN ). After IC101 has reset itself it gives a further reset to the audio processing IC, IC305 via pin 45 ( RESETOUT ).
CA10 Course Notes Data communication Within the CA10 chassis, there are a number of data control signals that pass to and from the main system microprocessor, IC101. There are two basic types, serial and parallel as shown in the diagram below. Figure 13 : Data Communication of IC101 I2C bus There are two I2C buses used to communicate serial information to and from IC101.
CA10 Course Notes Protection circuits There is a protection input on IC101, pin 77 ( PROT ) which causes the set to shut down should there be a fault with the audio output stage. When the audio output is operating correctly, the feed to the loudspeaker will have an average DC level of zero volts. If an imbalance were to occur whereby the signal became predominately more positive or negative, this could lead to failure of the audio output devices or loudspeaker.
CA10 Course Notes Line Stage Line signal generation is carried out within IC201, with synchronisation being supplied by the incoming sync pulse. The line stage generates various supplies, including EHT, focus, G2, A1 and heaters and the line scan coil drive signal.
CA10 Course Notes Once IC201 has detected a feed back pulse, it will switch the line drive signal frequency to the correct running rate of 15.625kHz. At this point the supplies from the chopper stage are not used and those generated by the flyback transformer, T601, will take over.
CA10 Course Notes Line output circuit description To enable enough emf to be generated by the line stage in this 59/66cm chassis, it is necessary to provide a high HT voltage of 150VDC. This is fed into the line output transformer, T601, at pin 2 as shown in the diagram below, note that there is no feed resistor into the transformer. Figure 17 : Line Output Circuit From the collector of the drive transistor, Q601, the line drive signal is fed into the base of Q602.
CA10 Course Notes Figure 18 : Line Current and Voltage Waveforms ( Idealised ) Note that as the voltage across the primary winding is proportional to the rate of change of current in it and since the rate of change is constant during the forward scanning stroke, but fast during the flyback period, the voltage across it ( and the scanning coils ) will be a series of pulse. This is also shown in the diagram below.
CA10 Course Notes Figure 19 : Sand Castle Pulse Figure 20 : Sand Castle Pulse Detail R625 and R626 provide a load for the line pulse and R615 limits the current/voltage supplied. C618 suppresses any high frequency signals that may occur on the line pulse. These would be undesirable as they may cause unpredictable false triggering within IC201. D607 and D824 ensure that no erratic negative going pulses are present on the line signal.
CA10 Course Notes East/West correction Principle of circuit operation If the width of the picture were not varied during the line scanning process, it would result in a picture that would be wide at the top and bottom, but narrow as it progresses towards the centre. This effect is especially noticeable on large CRT’s due to the distance the beam has to travel. The circuit used to correct for this distortion is called the east/west correction circuit and is described below.
CA10 Course Notes top of this capacitor will be in excess of 160V peak. The start point of the two waveforms on the cathode of D507 ( 60V peak ) and the anode ( 160V peak ) will occur at the same time, but the cathode will turn off sooner ( determined by the modulating input signal of Q506 ). This being the case, the signal on the anode of D507 will be modulated with amplitude variations on each line pulse, and these variations will vary depending upon the point at which they occur in the parabola.
CA10 Course Notes Figure 24 : Diode Modulator Circuit The obvious advantage of this circuit configuration is that Q506 and Q507 are only conducting during the active line scanning period. This coupled with the fact that they are used as switches, i.e. maximum current/no voltage or no current/maximum voltage means that there is very little energy generated within these devices. Thus power consumption is kept down to a minimum.
CA10 Course Notes Supplies generated by the line stage A number of conventional supplies are generated from the line output transformer, EHT, Focus, G2, A1 and CRT heaters. A further +/- 15V is also generated for the vertical output stage. Also there is a +2V supply for the east/west diode modulator and a -10V supply which along with the +2V supply is used to drive the line output transistor. See the Line drive circuit description section of these notes for more details on this.
CA10 Course Notes Beam current limiter Beam current limiting is carried out to remove the risk of forward X-ray emissions, to stabilise the EHT and control picture brightness. Feedback to control the beam current is taken from the bottom end of the EHT over winding as shown in the diagram below. Figure 26 : Beam Current Limiter Circuit Feed back for the beam current limiter is taken from the bottom end of the EHT over winding on pin 8 of T601.
CA10 Course Notes The signal on pin 22 is a pulse ( at vertical rate ) sitting on a DC pedestal of three volts ( nominal value as this varies anywhere between +1V and +4V ). Vertical circuit failure - CRT protection If the vertical drive were to stop, a bright white vertical line will appear across the centre of the CRT. This is obviously undesirable as it may burn the phosphor coating if left on for too long.
CA10 Course Notes Vertical Stage Vertical time base generation A R/C oscillator within IC201 provides a vertical drive signal for the vertical drive and output stages . External components are used to control the stability and phasing of this signal ( note that the external crystal is not used as a reference source - the vertical stage will operate with this component disconnected from the circuit ) When a video signal is present, this oscillator is locked to the incoming vertical synchronisation pulse.
CA10 Course Notes Figure 29 : Vertical Drive Circuit Vertical scan coil drive circuit Page 28 Sharp Electronics (UK) Limited CE Technical Support Group
CA10 Course Notes The vertical output stage used in the CA10 chassis is based around two field effect transistors - Q501 and Q502. As power consumption and therefore heat generation needs to be kept to a minimum a class D amplifier type configuration is utilised. This basically means that the FET’s are used as switches to switch either the +15V or -15V into the output load ( in this case a low pass filter ) then into the vertical scanning coils.
CA10 Course Notes Figure 30 : Vertical Output Stage Tuner and IF Page 30 Sharp Electronics (UK) Limited CE Technical Support Group
CA10 Course Notes Tuning and IF control is provided by the system microprocessor, IC 101 via the I2C bus line. The tuner itself is a digitally controlled device, which eliminates the need for a separate VT line generator circuit. As the tuner is controlled directly from the microprocessor, it is easier to provide direct channel entry and as an added feature the set is also equipped with auto channel sorting. This is across the normal UK channel band and cable channels.
CA10 Course Notes this is provided from the +150 volt line via the dropper resistors R211, R213 and R214 and IC202. IC202 is effectively a 32 volt high stability zener diode. Other supplies need to be present to make the tuner work correctly. Although there is only one other supply source ( +5V ) this is used internally for the digital to analogue converter, RF amplifier, tuning stages and IF processing circuits.
CA10 Course Notes into two paths. The first path goes into the base of Q203 via the a 6MHz filter CF202 which removes the audio IF signals from the composite video signal, the second path is via C304 and the high pass filter C334, L302, C335 and R309 into the base of Q301 which removes the video signal from the audio IF signal.
CA10 Course Notes Figure 33 : Spectrum of the Base Band Signal Each signal path from IC201, pin 6 will now explained in more detail below. Audio IF processing C304, being of a very small capacitance, will only pass relatively high frequencies which will effectively remove any signals below about 5MHz. This coupled with the filtering network of C334, L302, C355 and R309 ( effectively a high pass filter ) will ensure that only the audio FM carrier at 6MHz and the NICAM carrier at 6.
CA10 Course Notes RF AGC operation As signals received from off air transmissions can vary tremendously from area to area, it is necessary to provide some form of automatic gain control on the incoming RF signal. The circuit shown below performs this action. Figure 34 : Automatic Gain Control Circuit It can be seen the at the heart of the system is the main system microprocessor, IC101.
CA10 Course Notes Audio Processing In the current range of models fitted with the CA10 chassis there is the possibility of three different sound output types. These are mono, stereo ( NICAM or AV ) and SRS ( Sound Retrieval System ). The schematic diagram below shows the circuit arrangement for a typical SRS model. Figure 35 : Audio Stage Circuit Diagram As can be seen from the diagram shown above, all the audio signal processing is undertaken by IC305 ( MSP3410D ).
CA10 Course Notes Note that SRS is provided on some models ( 51DS05H, 59DS05H and 66DS05H ) and this system is described in more detail in the Sound Retrieval System ( SRS ) section of these notes. Signal sources and generation Audio signals come from four different sources, which are listed in the table below. Note that the IF input from the tuner is decoded within IC305 to produce the normal FM mono and stereo NICAM signals.
CA10 Course Notes Sound Retrieval System ( SRS ) In the current range of models fitted with the CA10 chassis there is the option of three different types of sound output. These are mono, stereo ( NICAM or AV ) ans SRS ( Sound Retrieval System ). Dolby Prologic models are provided in the previous chassis range in the 59CSD8H and 66CSD8H which will continue to be produced alongside the CA10 models.
CA10 Course Notes Video Processing IC201 provides the majority of the signal processing functions and is controlled by the I2C bus 1 line from the main system microprocessor, IC101. Video signal switching is carried out by IC401 which also provides Y and C inputs to IC201. Teletext, RGB and on screen display information are also fed into IC201, which then outputs these signals to the CRT drive amplifier, IC901.
CA10 Course Notes Signal sources and switching Video signals can either be obtained from the tuner ( RF channels from 20 to 69 ), front AV, rear S-VHS or the two SCART sockets located on the rear of the receiver - one of these is designated RGB. RGB signals also come from the teletext processor for text and for the on screen display, these are discussed further in the Teletext , RGB switching and On screen display sections of these notes.
CA10 Course Notes RGB Switching Figure 38 : RGB Input and Switching Circuit It is possible to feed in a RGB signal ( computer, games console, etc. ) to this receiver via the RGB SCART socket located on the rear of the receiver. Switching for this input is either via direct selection on the remote control or by automatic switching using the fast switching pin on the socket, pin 16.
CA10 Course Notes Teletext Teletext processing is carried out within IC106 ( STV5346 ). This IC is a 28 pin dual in line flat pack that contains all the normal fast text processing capabilities including a small page store and on screen display generation. Figure 39 : Teletext Processor Circuit When the user selects the teletext function, IC101 instructs the teletext processor, via the I2C bus 2 line, to switch IC201 to the RGB input via pin 12 of IC106.
CA10 Course Notes CRT drive circuit Drive for the CRT cathodes is provided on the CRT base panel. Most of the amplification is carried out within one IC, IC901 ( TDA6107Q ). To enable IC901 to work correctly it requires a supply of 150V, which is taken from the main HT off the chopper power supply.
CA10 Course Notes Indicating Devices Figure 41 : Stereo and OPC LED Drive Circuit There are three indicating devices used within the CA10 chassis. The first of these is the standby indicator, which is a neon connected across the live and neutral mains input, after the mains switch. This will illuminate whenever mains is applied to the set. The second indicator is the stereo LED.
CA10 Course Notes Practical Fault Finding I2C bus line disconnection It is possible to isolate the various devices controlled by the I2C line by removing the feed resistors. A different symptom will be apparent depending upon which device is isolated as described below. Tuner If the tuner is isolated from the I2C bus line by removing resistors R201 and R202, all functions will work correctly except that there will be no picture, i.e. there will be no output from the tuner and a snowy raster will appear.
CA10 Course Notes Power supply voltage line resistances to earth Some times it is necessary to ensure that the supply lines are not loading the power supply unnecessarily. To this end it is useful to have an approximate static resistance of each supply. Typical readings are shown below. Measured Voltage Measuring Point Resistance Pin of T701 +18.1V Cathode of D718 =>1k 8 -18.0V Anode of D719 =>1k 3 +149.7V Cathode of D720 =>50k 4 +10.2V Cathode of D721 =>5k 5 +7.
CA1 Course Notes Introduction to the CA1 Chassis As the CA10 chassis is designed for use as a NICAM and fast text unit, it is not suitable to be used in the small screen models that only feature basic functions. For this reason, the Sharp development engineers at the Spanish factory, located in Barcelona, have designed a small screen chassis, this is designated the CA1.
CA1 Course Notes CA1 Receiver Specifications Features 37DM23H 37DT25H 51DT25H Tube Size ( inches ) 14 14 21 Visible Screen ( cm ) 34 34 51 Tube Type Tinted Tinted B Matrix Number of Pre-sets 99 99 99 Fast Text No Yes Yes On/Off Timer Yes Yes Yes Rear S-VHS Input - - Yes 21 Pin Euroscart 1 1 1 Power Output ( MPO ) 2 2 4 Headphone Jack Yes Yes - Stand No No Yes Width ( mm ) 366 366 539 Height ( mm ) 325 325 468 Depth ( mm ) 375 375 484 S/B Power 9
CA1 Course Notes Block Diagram of the CA1 Chassis A block diagram of the CA1 chassis is shown below. It can be clearly seen from this that the sound processing and teletext IC’s have been deleted. All audio decoding is carried out within IC201 and the teletext function ( 37DT25H and 51DT25H ) is carried out by the masked microprocessor ( IC1001 ).
CA1 Course Notes CA1 Power Supply The power supply used in the CA1 chassis is very similar to that used in the CA10, except that its current suppling characteristics are lower and it does not turn off while the receiver is in standby. Therefore IC702 is not fitted and the power consumption of this receiver will be higher than that of the CA10, at approximately 9.5W.
CA1 Course Notes the base of a control transistor. The collector of this transistor will affect the brightness of the LED inside the opto coupler and hence the conduction of the photo transistor. Regulation is achieved by varying the on time of the chopper transistor. If the main supply were to rise, the voltage on the base of Q705 will also rise, turning it on harder. The brightness of the LED would increase as the voltage on pin 2 of the opto coupler drops.
CA1 Course Notes CA1 Reset Whenever the receiver is switched on from the mains ( on/off button pressed ) it is necessary to reset the main microprocessor, IC1001. This process is achieved with the use of the circuit outlined below. Figure 45 : CA1 Reset Circuit When the power supply starts up, a permanent +5V line , designated +5Va, will be generated via D712 and series regulator Q704.
CA1 Course Notes Data Communication Figure 46 : CA1 Data Communication To enable the receiver to work correctly it is necessary to provide some form of communication between the microprocessor and the NVM and IC201. This is provided by a single I2C bus from pins 43 ( SDA ) and 54 ( SCL ) of IC1001. This configuration is considerably simpler than that of the CA10 chassis. A clock is provided at 18MHz to control the internal processing of IC1001.
CA1 Course Notes CA1 Power On Control During the stand by mode, IC1001 ( main microprocessor ) is supplied with the standby +5Va from the chopper stage on pins 11 and 37. This supply is generated by the series regulator transistor Q704 from the supply generated by D712 off pin 9 of T700. Figure 47 : CA1 Power On Control Circuit To enable the set to turn on, pin 4 of IC1001 goes low, which turns off Q1007 and allows its collector voltage to rise up to 5.
CA1 Course Notes CA1 Protection Figure 48 : CA1 Protection Circuit Unlike the CA10 chassis, the CA1 incorporates a protection circuit that operates with inputs from the beam current limiter, frame output stage and CRT drive amplifier supply. Basic protection is provided should the frame drive or beam current feed back drop below 1.5V on pin 7 of IC1001 ( PROT ).
CA1 Course Notes CA1 Discrete Component Vertical Stage Unlike the CA10 chassis, the vertical output stage used in the CA1 chassis is a discrete component type circuit. The circuit descriptions below explain the function and operation of the vertical driver and output stages. Note that a very similar circuits are used in previous ranges of Sharp small screen television receivers.
CA1 Course Notes Vertical Output Stage Figure 50 : CA1 Vertical Output Stage Vertical drive waveform comes from the differentiation circuit Q507, 508, which combines the two outputs from IC201 on pins 63 ( VERT B ) and 64 ( VERT A ). From this stage the waveform including flyback pulse is fed to the base of Q506 which along with Q505 is connected in a Darlington configuration, providing a high gain stage.
CA1 Course Notes being a pulse which is used for the flyback generation. At the collector of Q505 is a waveform with a positive going flyback pulse, effectively this device is connected as a class A output with R512, D502, R501, R503 and R508 as its collector load. This waveform is fed directly to the base of Q504 the first of the two output transistors. This is a PNP transistor connected as an emitter follower providing unity voltage gain and high ( Hfe ) current gain.
CA1 Course Notes CA1 Line Stage Within this chassis, the line driver stage does not use a coupling transformer, but a push pull driver stage, which is similar in operation to that of the S3B chassis ( DV5131H and DV5150H ), however a few refinements have been made to the circuit. Driver Stage Figure 52 : CA1 Line Driver Stage There are a number of similarities between the circuit shown above and that of the CA10.
CA1 Course Notes primary winding of the line output transformer. A pulse is fed back from pin 10 of T601 to indicate to the line time base generator that the stage has started up. At this point the drive signal changes frequency from 32.25 kHz ( twice line frequency ) to its normal running frequency of 15.625 kHz. Also at this time, to enable the output transistor to draw enough current to maintain its secondary voltages, its base current must increase significantly.
CA1 Course Notes CA1 CRT Drive Amplifier Unlike the CA10 chassis, the CA1 does not use a single IC for driving the CRT cathodes, instead a discrete component amplifier is used. The diagram shown below shows the red channel only.
CA1 Course Notes CA1 Audio Output Amplifier To enable the CA1 chassis to reproduce audio signals through a conventional loudspeaker, a linear push-pull amplifier is used. The circuit diagram is shown below.
CA1 Course Notes CA1 Service Set Up Mode To adjust the preset values contained within the NVM it is first necessary to enter the Service Mode, this is described below :1. 2. 3. 4. Ensure that the receiver is on and displaying a picture, then switch it off using the mains switch. Press the volume down button and the channel up button simultaneously. Whilst still holding down the above buttons, switch the receiver on using the mains switch. Continue holding the buttons until a picture appears.
CA1 Course Notes CA1 Non Volatile Memory Codes All user setting are contained within the non volatile memory, IC1002 including a number of pre-set receiver parameters. Although these are pre-set for the model, they can be changed. Under normal circumstances this would serve no purpose, as the circuitry to preform the various functions may not be fitted. However, should a data corruption occur, or there is a need to modify the software, the locations and functions are shown below.
CA1 Course Notes 17 Luminance Delay - PAL 18 Luminance Delay - SECAM 19 S-Correction 1A Automatic Gain Control 1B Bit 0 : Bit 1 : 0 = No Front AV Sockets Fitted, 1 = Front AV Socket Fitted Bit 2 : 0 = Tuning Unlocked, 1= Tuning Locked ( Hotel Mode ) Bit 3 : 0 = All Band Tuning, 1= UHF Band Tuning Only Bit 4 : 0 = PAL System Only, 1 = PAL and SECAM Systems Bit 5 : 0 = Child Lock Disabled, 1 = Child Lock Activated Bit 6 : 0 = Manual Tuning, 1 = Automatic Tuning Bit 7 : 0 = OSD Symbols, 1 = OSD in En
CA1 Course Notes 32 Aging on.
CA1 Course Notes 4E Password First Digit 4F Password Second Digit 50 Password Third Digit 51 Password fourth Digit 52 Free 53 OSD Word 1 Bit 0 : OSD Program Size - 0 = Large ( 14" ), 1 = Short ( 21" ) Bit 1 : OSD Program Displayed Time - 0 = Short Time, 1 = Long Time 54 Red Reference for Auto BKGD Adjustment 55 Green Reference for Auto BKGD Adjustment 56 Blue Reference for Auto BKGD Adjustment 57 Control 2 : OSO, VSD, CB, BLS, BKS, CS1, CS0, BB 58 Control 3 : HOB, BPS, ACL, CMB, AST, C
CA1 Course Notes Binary code Button on remote to toggle 1 0 1 0 7 6 5 4 0 1 0 1 3 2 1 0 In the example given above, the hexadecimal code is A5, the binary equivalent is 1010 0101 and the remote control button to toggle each bit on or off, i.e. a 1 or a 0 is shown below the binary code. Therefore to change this to A6, remote control buttons 1 then 0 would be pressed. NVM Programming Application One application for entering the NVM set up mode is to enable the Hotel Mode as described below.
CA1/CA1 Course Notes Future Developments Sharp are currently developing two wide screen models to be introduced into the UK market place sometime at the start of 1998. These are the 76DW18H and 66DW18H models and will be fitted with the CA100 chassis. Both receivers have the same specifications, except for CRT size.
CA1/CA1 Course Notes Faults Page 70 Sharp Electronics (UK) Limited CE Technical Support Group
CA1/CA1 Course Notes Notes Sharp Electronics (UK) Limited CE Technical Support Group Page 71
