GALLIEN-KRUEGER gallienkrueger backline100service free download

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Service Manual Backline 100 Table of Contents Operating Instructions 3 Turn On / Calibration Procedure 7 Schematics 9 Engineering Change Orders (ECOs) 17 Bill of Materials 24 Backline 100- Lead Amplifier Turn-On Procedure GK Document # 420-0093-C Board #'s: 206-0093-C (pre amp), 206-0094-C (power amp) Backline 100- all options 12/9/92 Rev. 11/23/99-SW SETUP 1) Variac on zero, power switch off- connect power cord. 2) Connect output to load box with both sides connected together. 3) Resistance loads open (switch in center), speaker on. 4) 1X probe to scope-A. 5) Load box to scope-B and AC-VM. 6) Set oscillator on 200Hz sine wave @5mVrms (-26dBV). 7) DVM on 20mV range. 8) AC voltmeter on 30V range. 9) Scope-B on 10V/cm (or 5V uncalibrated ). 10) Scope sweep on 1ms/cm, scope trigger on B. 11) Connect reverb wires from preamp - red to output of reverb. 12) On Backline Front Panel, set knobs to 0, switches out. POWER SUPPLY ANY POWER AMP TEST 1) With power switch on, gradually increase variac to 50V. Listen to speaker and watch scope for no current draw. 2) Check preamp supplies- +/- 16VDC (+/- 1V margin). 3) Adjust variac to 120V and turn speaker off. 4) Set bias. Hook DVM across collectors of Q6 and Q81 and adjust R50 (on '94 board) for 2mV across power resistors (R11, 24,57,79). 5) Connect oscillator to return (200Hz @ -26dBV). Output = 9Vrms. 6) Increase oscillator to