Training Manual Multi-Product Hi-Fi Technology and Troubleshooting Digital Board Hi-Fi Output Model: STR-DE845 Troubleshooting Switching Power Supply Super Audio CD Model: DAV-700/900 New Technology DAV-S500 HCD-S500 HCD-C700/900 Course: A-124...
1. Introduction Introduction Purpose The focus of this book is on the digital board operation in the sample receiver (STR-DE845) and covers the following subjects: • A working understanding of sound fields and what type of movie or music software should be used with each sound field for optimal performance.
2. Sound Fields Sound Fields What is a Sound Field? Each venue, be it a concert hall, cinema theater or small jazz club, has a characteristic “sound field” made up of direct sounds and reflections from the surfaces of the environment. Some venues sound large and spacious, others sound small and intimate.
2. Sound Fields Note: Front Left – FLT Low Frequency Effects - LFE Center – Cntr Front Right – FRT Rear Left – RLT Rear Right - RRT Listening Position – LP FIGURE 2-2 Virtual The five different Virtual modes create sets of virtual speakers using the actual existing speaker system which could be a six or three speaker system.
Page 6
2. Sound Fields 2) V. Multi Rear: Uses 3D image processing to create three sets of virtual speakers from a six-speaker system (two actual rear speakers; ref. Figures. 2-6, 2-7 and 2-8). The position of the rear speakers (Side, Mid or Rear) must be programmed in the A/V receiver SET-UP menu for this sound field effect to work properly.
Page 7
2. Sound Fields FIGURE 2-10 5) Virtual Enhanced B: Uses 3D image processing to create one set of virtual rear speakers. This is accomplished using only the front left and right speakers without using actual rear speakers (ref. Figure 2-11). FIGURE 2-11...
(e.g. The Kim Novak Studio is particularly good for Science Fiction movies). The Sony Entertainment Scoring Stage is an actual studio used for recording the music portion of the movie. Once again, this studio has especially good characteristics for recording movie sound tracks.
2. Sound Fields Theater There are four theater sound fields: 1) Night theater: Retains theater-like sound characteristics while listening at a low volume level, ideal for late night movie viewing. 2) Mono Movie: Creates theater-like sound characteristics from movies with mono soundtracks. 3) Stereo Movie: Creates theater-like sound characteristics from movies with stereo soundtracks.
Page 10
2. Sound Fields 3) Speaker wires must be connected correctly, e.g. the Positive (+) on the receiver terminal connected to the Positive terminal on the speaker. Same for the Negative (-) terminal. 4) The speaker impedance switch on the receiver should match the impedance of the speakers connected. Note: If only output “A”...
Page 11
2. Sound Fields T A B L E 2 -1 - IN P U T S O F T W A R E F O R M A T D o lb y D ig ita l (A C -3 ) S te re o D o lb y P ro lo g ic P C M...
3. Digital Board Inputs Digital Board Inputs Analog Inputs 2 Channel Stereo Inputs There are nine analog inputs on the digital board. They are as follows: Tuner Phono MD/Tape TV/SAT DVD/LD Video 1, 2, 3 These inputs enter the digital board as analog audio and supply one of the following audio formats: Mono, Stereo or Dolby Prologic.
Page 13
DE845 (REAR VIEW) IN AUDIO OUT A IN AUDIO OUT 2ND AUDIO ANALOG INPUTS PHONO DVD/LD MD/DAT TAPE DEVICES TV/SAT SOFT WARE DOLBY SURROUND DOLBY PROLOGIC STEREO MONO FORMATS FIGURE 3-1 - STR-DE845 ANALOG & DIDITAL INPUTS 13CA124 1380 10/15/01...
3. Digital Board Inputs Figure 3-1 illustrates the typical devices connected to the various receiver inputs and what software formats are compatible with each input. NOTE: The audio from the Tuner antenna section is also an input to the digital board. It is processed the same as any of the other analog inputs in order to apply the desired sound field effects.
Page 15
3. Digital Board Inputs Figure 3-3 illustrates the encoding and decoding Dolby Digital and DTS 5.1 channel formats. These formats are encoded into a digital data stream only, such as a DVD disc, Satellite signal, etc. (no analog encoding). There are actually six channels in the 5.1 channel format (Left, Right, Center, Subwoofer or LFE, Left surround and Right surround).
4. Control Signal Block Control Signal Block Input/Output Select ICs Control Signal Block DIGITAL BOARD AU SW BOARD MAIN BOARD ANALOG INPUTS REAR PANEL JACKS TO IC304/ IC1101/ IC1005 PINS 3 & 5 IC303 PIN 3 DIGITAL ANALOG 2 CH. MODE IC304/ INPUT INPUT...
4. Control Signal Block Data and Control Line Waveforms for IC1301 and IC502 Oscilloscope Settings: 5v/div. 100us/div. PIN No.46 5Vp-p DC coupling (R1202) Trigger rising edge WAVEFORM 4-1 PIN No.48 PIN No.47 5Vp-p 5Vp-p DATA (R1204) (R1203) WAVEFORM 4-2 WAVEFORM 4-3 Digital Processing ICs Control Signal Block 12.282MHz MCLK...
Page 18
4. Control Signal Block Circuit Description Data, Clock, and Chip Enable Lines The control lines for IC1401 (IC1201/parallel data lines 17 to 24, pin 25 (address line) and pin 16 (CE)) and IC1503 (IC1201/pins 30 (data), 29 (CLK) and 28 (CE)) are only present during input switching. The waveforms on the control lines are the same as those shown in Waveforms 4-1, 4-2 and 4-3, except standby voltage state is high (5V dc).
Page 19
4. Control Signal Block Reset lines and Crystals The main Reset line is applied to IC1201/pin 90. During normal operation, this line is High (5V dc). The other Resets are output to IC1101/ pin 48 (normal high 5V), IC1301/pin 62 (normal high 5V), IC1503/pin 17 (normal high 5V) and IC1401/pin 26.
Page 20
4. Control Signal Block waveforms is the amount of activity in each mode. The first two modes (AFD and 2CH) show very little activity because no reverberation is necessary and all the processing is being performed in the DSP internal RAM. The third mode, where any of the Cinema studio and Hall modes can be selected, shows increased activity.
Set the DVD to output Dolby digital; this is done in the DVD menu (audio section) in the STOP mode. • Set the STR-DE845 to the DVD/LD input (digital cable should be connected to the DVD/LD input) and AFD mode.
5. Analog Signal Block Description: This will exercise the Front Left, Front Right, Center, Left Surround and Right Surround channels. So, data can be viewed on IC1301/ pin 24 (SOA Front Left/Right), pin 23 (SOB Center/Subwoofer), and pin 22 (SOC Rear Left/Right). Reference Waveforms 5-3, 5-4 and 5-5 for example waveforms on IC1301/pin24, pin 23 and pin 24.
Page 23
5. Analog Signal Block The signal from the analog switching ICs (IC301and IC303) passes through Buffer IC304 (located on the Main board), and then splits off in two directions after CNP11. One path is to IC1502 (Output Select IC), which is used when the receiver is set to 2CH mode.
Page 24
5. Analog Signal Block NOTE: There is no data present on the SOB and SOC lines in the following sound fields: Mono, Stereo and all Hall modes. There is data only on SOA in these modes. Channel designation for SOA, SOB and SOC are as follows: SOA ————...
6. Digital Signal Block Digital Signal Block R1001 REAR L/R IC001 DATA IN 100Ω IC1301 OPTICAL D/LD IC1101 CENTER SUB DOLBY RECEIVER IC1005 DIGITAL DIGITAL R1002 DIGITAL FRONT L/R AUDIO 100 Ω AUDIO IC1002 INPUT DECODER SAME AS ANALOG OPTICAL SELECT RECEIVER BLOCK CIRCUIT...
Page 26
6. Digital Signal Block The desired input signal is selected by IC1005/ pin 7(Digital Input Select). The input signal is then applied to IC1101/pin 3(Digital Audio I/F Receiver) .The digital signal format is still S/P DIF. The Digital Audio I/F Receiver takes the S/P DIF format, strips off all of the overhead control data and sends the sound data (e.g.
QV S.W. BOARD R1241 R1247 Ω Ω R1218 Ω Q1203 C1214 2200pf NOT USED ON STR-DE845 NORMAL NORMAL IC1201 SYSTEM CONTROL FIGURE 7-1 - MUTE SIGNAL BLOCK 4A124 1/21/02 Circuit Description NOTE: Reference figure 7-1 for the following circuit description.
8. Troubleshooting Block Troubleshooting Block Aside from confirming the normal operating signals and voltage already discussed in this course, the digital board can be troubleshot by dividing the board into specific sections using various normal operating modes. Figure 8-1 and the text below will describe how this can be accomplished. 5.1 CH.
Page 29
8. Troubleshooting Block 4) Set the receiver for AFD or any Sound Field (e.g. Normal Surround), and select a Digital Input to set up and test the following signal path: Digital input ⇒ IC1005 ⇒ IC1101 ⇒ IC1301 ⇒ IC1403 ⇒ IC1401 ⇒ Partial IC1503 ⇒ IC1502 ⇒ Audio Amps ****ICs bypassed are IC304, IC1504, IC1554 and Partial IC1503 (Input Circuit) 5) The DSP/SRAM Self Test can be performed to check the operation of the DSP (IC1401), SRAM (IC1402)
9. DAV-C700 Switching Type Power Supply DAV-C700 Switching Type Power Supply This switching power supply description and troubleshooting currently applies to these three Sony models: • DAV-S500 (HCD-S500) • DAV-C700 (HCD-C700) • DAV-C900 (HCD-C900) Switching Power Supply Advantages Although switching power supplies have the disadvantage of containing more parts than a 60 Hz. power transformer...
Page 31
9. DAV-C700 Switching Type Power Supply Power Supply Control See Figure 9-1 for the control of the power supply stage. In this A/V product there is: • A front panel latching master power ON/OFF switch (S901) that applies AC power to the product; •...
Page 32
9. DAV-C700 Switching Type Power Supply This switching power supply actually has four modes of operation: OFF, Standby, Power ON and power ON in DVD. In the OFF mode, S901 is open. In the standby mode, S901 closes, the oscillator (IC901) outputs in bursts and the error regulator (IC902) is disabled (by D912) to prevent the oscillator from shutting down.
Page 33
9. DAV-C700 Switching Type Power Supply If a circuit failure disabled D912, error regulator IC902 would be operational, outputting a correction voltage of about 0V to Switching regulator IC901/pin 1 in this oscillator burst (standby) mode. This 0Vdc is output because IC901 is producing less power (outputting only bursts), but error regulator IC902 outputs 0V attempting to raise the output to normal.
9. DAV-C700 Switching Type Power Supply To do this, P.Cont 1 turns ON Q915, which forces Inverter IC907 to output a HIGH at pin 4 for PC902. The transistor in isolator PC902 turns OFF, allowing switches Q901 and Q902 to fully conduct (via R905). As a result, the entire regulated 20Vdc from regulator Q903 (emitter) is applied through Q902 (e-c) into switching regulator IC901/pin 4.
9. DAV-C700 Switching Type Power Supply T901’s output voltages are dependent upon the match between its resonate frequency and the input frequency from the oscillator (IC901). When IC901’s oscillator frequency is the same as the T901-C916 resonate frequency, there is maximum power transferred from T901’s primary to secondary, producing maximum output voltage (peak of Figure 9-4’s bell curve).
Page 36
9. DAV-C700 Switching Type Power Supply Power Supply is Dead Normally when you press the front panel ON switch, the CPU (on the DVD board) is powered with 5.6Vdc. The unit can then power ON when you press either the front panel Play or one of the five Eject buttons. The display will then illuminate, showing the unit’s model number and then the input mode - “DVD”.
9. DAV-C700 Switching Type Power Supply • Remains at 0V - CPU IC901 on the DVD board is not outputting this power ON command. • Goes to 4.7Vdc - the problem is on this power supply board. Go to step 11. 11.
9. DAV-C700 Switching Type Power Supply 3. Plug the unit into AC and press the front panel Power ON switch so it latches in. The power supply should start and produce the following voltage. See Chart 9-7 below: Chart 9-7 - No Load Power Supply Output Voltages – Use Cold Ground Location No Load Voltage Normal Power ON Voltage...
10. Hi-Fi Output Troubleshooting Overview Hi-Fi Output Troubleshooting Overview Troubleshooting Audio Power Amplifiers is frequently a matter of simply changing a pair of output transistors. Other times the protection light just will not go off. In the worst-case scenario, the newly replaced transistors are destroyed as power is applied.
Page 40
10, Hi-Fi Output Troubleshooting Overview AUDIO OUTPUT BIAS DRIVE NETWORK RELAY OUTPUT FIGURE 10-2 10.2A124 10/26/01 Problems with the bias network usually cause excessive current draw. In rare cases, bias network problems may cause crossover distortion. Problems with the Driver amplifier cause small DC offset voltages to appear at the amplifier’s output (speaker connection).
11. Troubleshooting Driver Amplifier & Bias Network Circuits Troubleshooting Driver Amplifier & Bias Network Circuits Protection light will not go off after replacing Output transistors Most modern Power Amplifiers use an IC package for the Drive Amplifier (shown in Figure 11-1). If you have small DC offset voltages at the Driver amplifier output, the protection circuit will be triggered and the receiver will enter the protection mode.
11. Troubleshooting Driver Amplifier & Bias Network Circuits In a discrete Driver amplifier circuit, DC offset voltages are usually caused by the differential amplifier stage (TR1 and TR2 are the internal differential amplifiers in the STK350-230, shown in Figure 11-1). The differential amplifier has two transistors with their emitters tied together.
Page 43
11. Troubleshooting Driver Amplifier & Bias Network Circuits Obviously the “Jumper Method” is much slower (but a lot safer) than the “Find the HOT transistor” method. I recommend practicing both methods as physical access limitations shift the advantage from one method to the other.
Page 44
11. Troubleshooting Driver Amplifier & Bias Network Circuits Once you have located the bad channel, it is time to shotgun (due to very few components) all the active components (diodes or transistors) in the bias network. Shotgunning is preferred since intermittent bias components can cause expensive damage to the Power Amplifier.
12. Troubleshooting Audio Protection Circuits Troubleshooting Audio Protection Circuits The most common problem in audio receivers is “protection” light is ON and no sound. The usual cause is one or more shorted Output transistors in one of the Power amplifiers. In many cases, you can find the source of the problem with an ohmmeter by checking the E/C junction of the audio Output transistors.
12. Troubleshooting Audio Protection Circuits (+/-) Offset Protection Circuit TO PROTECT L = PROTECT FIGURE 12-2 - +/- OFFSET PROTECT 12.2A124 11/20/01 Q1 and Q2 detect DC voltages at the Power Amplifier Outputs (Ch1 through Ch5). Both transistors have their emitters grounded.
12. Troubleshooting Audio Protection Circuits Over Current Protection Circuit TO PROTECT L = PROTECT Q100 R100 Ω Ω 1.5K 0.22 RELAY R200 Ω Ω 6.2K 0.22 Q200 POWER AMP FIGURE 12-3 - OVER CURRENT PROTECT 12.3A124 11/28/01 Since current in the Output transistors also flows through the 0.22 ohm emitter resistors, the voltage-drop across these resistors will be proportionate to the current in the Output transistors.
Super Audio CD Overview Developed by Sony and Philips in early 1982, the compact disc (CD) was a revolutionary development that overturned conventional thinking about audio media. Unlike the analogue recordings, which were mainstream at that time, the CD system converted music signals into digital signals for recording and playback. Users were amazed by the dramatic improvement in sound quality, the quick access and the handling convenience provided by the compact 12cm discs.
Page 49
13. Super Audio Cd ANALOG INPUT SIGNAL OUTPUT SIGNAL SHOWS TYPICAL BITS 000000 00000 01 11111 01 1111111 01 11111111 FIGURE 13-1 - DSD WAVEFORM 13.1A124 1392 11/1/01 Compared to PCM, in which numerical data is clearly demarcated, the digital data processed with DSD is extremely similar to the analogue data.
13. Super Audio Cd To combat the problem of software pirating, Super Audio CD utilizes Pit Signal Processing (PSP) technology to impose a faint image, or Watermark, on the signal side of the disc. The inclusion of this Watermark makes it easy to ascertain whether a disc is a fake, an effective means of protecting the rights of artistes and copyright holders.
13. Super Audio Cd SUPER AUDIO CD RECORDING PROCESS PLAYBACK PROCESS Input Output Delta Signal Signal Super Analog. Sigma Audio Low - ∆ Σ Pass Modu 64fs 64fs Filter -lator 1 bit 1 bit (Noise Shaping) CONVENTIONAL CD RECORDING PROCESS PLAYBACK PROCESS Output Input...
Page 52
13. Super Audio Cd 1-BIT QUANTIZER 1-BIT QUANTIZATION OUTPUT ANALOGUE SIGNAL INPUT FIGURE 13-3 - EXAMPLE OF 1-BIT QUANTIZER CONFIGURATION 13.4A124 1394 1/21/02 The difference between the shape of the incoming and outgoing wave forms (gray area, bottom of Figure 13-4) is known as quantization noise.
Page 53
13. Super Audio Cd In this way, ∆Σ modulation accurately expresses the level of the signal by adding a density characteristic (referred to as shadow density) to the pulse waveform. As opposed to PCM, which only handles the computed data, ∆Σ modulation converts analogue signals directly into a pulse stream of “0”s and “1”s.
Page 54
13. Super Audio Cd Additionally, the effects of noise in the upper range can be eliminated by passing the signals through an analogue low-pass filter at the time of playback. By incorporating ∆Σ modulation, the DSD format can achieve expanded frequency characteristics and a greater audible dynamic range.
13. Super Audio Cd Figure 13-9 illustrates the difference in outcome when a 10kHz square waveform is converted with the DSD format compared to the PCM format. A square waveform is made up of a fundamental waveform and multiple sine waves. That is, the square wave contains many odd-number harmonic waves. With CD’s PCM format, the wave cannot be reproduced beyond the second harmonic wave, resulting in a sine wave output that cannot exceed 20kHz.
Page 56
13. Super Audio Cd Separate Space for Multi=Track Recordings and Extra Data The Super Audio CD is standardized, with disc space reserved for multi-channel recordings of up to six tracks, extra data and audio signals, including conventional 2-channel stereo recordings. In short, allocated disc space ensures that Super Audio CD will be able to handle all future applications.
Page 57
13. Super Audio Cd Three Disc Variations Super Audio CD offers three types of discs (ref. Figure 13-11). The most elementary of these is the single-layer disc that contains one high-density (HD) layer of information. As mentioned previously, this disc provides a 4.7Cbyte capacity.
Page 58
13. Super Audio Cd Watermark Technology In order to fully protect copyrighted property, Super Audio CD utilizes Pit Signal Processing technology (PSP) to embed a Watermark, which consists of a controlled array of microscopic pits on the surface of the disc. PSP enables two types of Watermarks: an “invisible”...
Mute, which is activated by pressing the mute button on the front panel. IC1101 Digital Audio I/F Receiver (DIR) The DIR receives the Sony/Phillips digital interface protocol (S/P DIF) signal, which contains the necessary Overhead and Surround Sound protocol Data. The DIR separates the Surround Sound protocol Data (e.g. AC- 3, and DTS) from the S/P DIF signal and outputs it to the Digital Audio Decoder for further processing.