Lem AMP2.4 free download

File name Lem-AMP2.4 pwramp.pdf

Index 2 4 5 Technical Specifications, Introduction, Test Procedures & Adjustments Schematic Diagrams Layout & Spare Part List Warnings Notice Service must be carried out by qualified personnel only.Any tampering carried out by unqualified personnel during the guarantee period will forfeit the right to guarantee. For a correct operation of the instrument, after having switched off, be careful to wait at least 3 seconds before switching on again. To improve the device's specifications, the schematic diagrams may be subject to change without prior notice. All components marked by this symbol have special safety characteristics, when replacing any of these components use only manufacturer's specified parts. The (µ) micro symbol of capacitance value is substituted by U. The () omega symbol of resistance value is substituted by E. The electrolytic capacitors are 25Vdc rated voltage unless otherwise specified. All resistors are 1/8 unless otherwise specified. All switches shown in the "OFF" position. All DC voltages measured to ground with a voltmeter 20KOhm/V. Soldering point. Male connector. Female connector. M/F faston connector. Supply voltage. Test point. Flag joined with one or more flags with the same signal name inscribed. Logic supply ground. Analog supply ground. Chassis ground. Earth ground. SERVICE MANUAL v CODE: 270232w ATTENTION Observe precautions when handling electrostatic sensitive devices. Address GENERALMUSIC S.p.A. Sales Division: 47842 S.Giovanni in Marignano (RN) ITALY - Via delle Rose, 12 - tel. 0541/959511 - fax 0541/957404 GENERALMUSIC on the NET: http://www.generalmusic.com 1t TECHNICAL SPECIFICATIONS Dimensions: Weight: Power Requirements: (230Vac±10% 50Hz) Output Power: (8 stereo/parallel) (WxHxD) 483x44x310mm (1U) 8Kg 300VA 2x 130Watts 92Vpp 0.775Vrms (0dB) 30K 15K 32±0.5dB 10V/µS (8 stereo/parallel) (-0.2dB) (-3dB) (SMPTE 60Hz/7KHz 4:1) (THD+N) (unweighted) (1KHz) >400 20Hzч20KHz 10Hzч60KHz <0.1% <0.1% >95dB >70dB µ Before proceed to supply the amplifier check visually the internal assembly, if appears an evident damage find the most possible reasons that cause it. µ Check the wiring cables for possible interruptions or shorts. µ If the damage has burnt a printed circuit board don't try to repair it, replace with a new one. CN3 pin 3 =-15±1Vdc µ If one or more voltages don't correspond, check the rectifiers, capacitors and transformers disconnecting them from circuitry, refer to schematics. Channels Check µ The CH1 channel is on the left and CH2 channel is on the right of the chassis. µ These procedures are intended for one channel at a time, repeat these operation for the other channel. µ Verify, with the Multimeter, the insulation between the heatsink and the transistors collectors. µ Verify, with the Multimeter, the PTC resistor value (R133 connected across pin 8 an pin 9 of CN3), it must be between 50 and 200. µ SETUP: Connect the ch1 scope GND clip to CN102 pin 1 (GND terminal). Connect the ch1 probe tip to