LabGruppen Line-Xtension_Service_Manual电路图.pdf

Line Extension Circuit description and schematics for C 20:8X C 10:8X C 10:4X C 5:4X Some of the schematics included here are not complete, or up to date. They should be used for educational purposes only. RadioFans.CN 收音机爱 好者资料库 INDEX INDEX .2 SP20F Circuit description .4 Functional overview.4 Block diagram.4 Soft Start.5 Stand-by (Auxiliary) supply.5 Mains Detector.5 PowerGood_AUX.6 PowerOn.6 PFC.6 Resonant converter.6 PowerGood_2kW.7 Service tips.8 SP20F Schematics.9 AICO4b Circuit description.13 Power supplies and power up/down.13 Stand-by supply.13 Start-up.13 Local supplies.13 FanControl.14 Control Ports .14 GPI .14 GPO.14 NomadLink.14 Controller operation .15 Controller .15 Analogue measurements .15 Digital measurements.16 FanControl.16 Signal flow .16 Input circuitry.16 Analogue control and monitor.16 Limiters .17 Clip limiter.17 Current Limiter.17 Average Current Limiter.17 Protections.18 Turn off channels .18 Low Impedance.18 Short circuit.18 VHF.18 DC-Protection.18 Temp Protection.19 DIP-switches .19 Service tips.20 RadioFans.CN 收音机爱 好者资料库 AICO4b Schematics (Partly).21 SPSMR Circuit description.29 SPSMR - schematics.29 Front Panel .30 A10D Circuit description.32 Power supplies and power up/down.32 Supplies.32 Power up.32 Signal Flow .33 Enable/Disable of a channel.34 Protections.34 VHF.35 DC-Protection.35 Temp Protection.35 Crowbar.35 Limiters .35 Clip limiter.35 Service Tips.37 A10D Schematics (Partly).38 RadioFans.CN 收音机爱 好者资料库 SP20F Circuit description Functional overview The power supply SP20F is used in the C-Series line extension amplifiers. It incorporates: Universal voltage input, 90-265 VAC Power Factor Correction (PFC) Soft start Fast mains unplugged detector A highly efficient isolated resonant converter for the high power outputs. A standby supply also used for lower voltages. Block diagram Soft Start PFC When the mains cord is plugged into the wall, the following will happen: The rectified mains will through D5 start to charge the capacitor bank C22-C25. The soft start circuitry will make the capacitor tank charge slowly with low inrush current. R33 is used as a current sense resistor and Q7 and Q4 is used to slow down this event. The voltage over the capacitor tank will rise slowly, and after about 1-2 seconds it will have completed its inrush cycle and R33 is bypassed via Q5, thus shorting the entire soft start circuitry. The node that in the schematics is named 400V, will be Vin * 1,41 (for 220v Mains it will be 311V, for 110v Mains it will be 155v). The circuitry will remain in this state until the external “Power On” is activated from the input board (PWR_ON_CTRL). Stand-by (Auxiliary) supply When the capacitor tank has reached about 80VDC the standby supply will try to start. AUXILIARY This converter is a self oscillating type and will change frequency depending on its load. The high voltage (80VDC) is fed through R76 by NomadLink command, by GPI (only when Nomadlink is disabled by dip switch) or on the front switches. The Controller will scan the front switches for On/Off if front switches are Remote - On. The DIP switch is set to GPI. The circuitry for GPI 1 and 2 are identical. If GPI1a and GPI1b are connected to each other, current flows through Q427. This opens Q421 and pulls this down through R486. This signals to the controller that the GPI1 is activated. During normal mode, by closing these connectors for more than 100ms will make the amp go on and when closing them again a second time the amp will go off. The same goes for GPI2. By activating the dip switch “GPI2 level trig” GPI1 is discarded. By closing GPI2 for more than 100ms the amp will go on. When opening GPI2 for more than 100ms the amp will go off. GPO NLIB/GPIO There are 2 semiconductor relays that control the GPO ports. By driving current through the diode the relay closes. The GPO2 is connected to the local +5v, so this will be activated as soon as the amplifier is on. The GPO1 is connected to the controller serial circuitry and will be activated by the controller when there is a fault on any channel. NomadLink NLIB/GPIO NomadLink is a transformer isolated serial communication network. Communication that comes into the IN port will only reach this device. Communication on the Out port will be directly transferred to the IN port. U417 has the capability to electrically exchange these ports so they switch functionality with each other. This is done when devices receives communication on the Out port only, and is controlled by the controller N/R pin, 0v means normal, 3,3v means switched ports. When NomadLink is turned off by the dip switches, the controller pulls NMLOn* to 3,3v. This disables the NomadLink completely by opening all the switches inside U417. The NMLOn* should be close to 0v normally. UPcBWhen no communication is present (NML cable unplugged), the processors transmission pin (Tx) pin will be internal disconnected and will be 1,65v because of the voltage division between R461 and R470. NLIB/GPIO this voltage will be gained in U413(1,2,3) to be 2,5v which will go through R473, through the transformer and end up at C432. U413(5,6,7) will in this state only transfer the 2,5v DC to its output, and through R462, through the transformer and to C433. U414 will detect any communication and in idle it will leave a high output of about 3,3v. During communication all these voltages will have an AC square wave signal on them, and it requires a digital storage oscilloscope to analyze them. If the DC voltages are correct, then it usually works. Controller operation All levels on the IO pins on the controller is interpreted as 2v as high (1). Any input that is more than 4,5v is hazardous to the controller pin. Controller The first criterion for the controller operation is that it has operating voltage on pin 5, 17 and 38. This should be over 2,7v (usually between 3,0 3,6v). The second criterion is that the RESET pin (4) is high. The third and final criterion is that the controller has a clock source. This could be measured on pin 8 of the controller using an oscilloscope. The wave shape does not need to be a perfect square wave shape; it looks more like a triangular wave. But it should run at the frequency of 7,37 MHz. During standby the controller uses the following pins: NMLOn* Out-port low - NomadLink on, high - NomadLink Off GPI Level In-port, Reading on dipswitch. GPIMode In-port, Reading on dipswitch. GPI1 In-port, Reading on GPI1 state. GPI2 In-port, Reading on GPI2 state. PwrOn/off In-port, Reading on Power On/Off switch state. RemOn/Man In-port, Reading on Remote On/Off switch state. NML Out-port, NomadLink direction. low = normal, high = switched PhSen In-port, high when NomadLink is connected Int0 In-port, PowerGood_Aux sense. Int1 In-port, PowerGood_105v sense. ComCt Out-port, controls ComLed, low =ComLed not lit, high =ComLed lit. MuteAll Out-port, when low all channels forced silent. PwrOnCt Out-port, when high the main PSU should start. When the controller goes into operating mode, 3 additional functions is started in the controller: Analogue measurements The Analogue measurements will start, for this to happen, the analogue to digital converter in the controller needs to be supplied. This is done via R436 to pin 27. This should be the same as the controller supply voltage (3,0 3,6v). The A to D converter also requires a reference voltage to function properly; this should be 2.49v 2.51v and could be measured at pin 29. U405 (on top schematics) will route the analogue level on its input pins to the controllers, AdIn pins, which are analogue input pin