Fat-1_Calibration_Procedure 电路图.pdf

FATMAN: FAT1 CALIBRATION PROCEDURE. The test signal is always 11 1kHz Sinewave. Start test with all push buttons out, Gains pots in mid-position, Compressor pots anti-clockwise. 1. POWER SUPPLY. Check Testpoint V+ for +15 vdc (:to.25v). Check Testpoint V- for -15 vdc (:t 0.25v). Check R29(Nr C84) for. Ilvolts dc (:tlv). Check R30 for approx 95 volts dc. (:!:5v). 2. OFFSET. Using a DC Voltmeter adjust RV6 for +400 mVat TP3. Press KNEE switch IN and check the voltage changes to +200 mV :t15 mY. 3. BIAS. Connect Input to Channell and adjust RVl3 for a reading of 0.5% Distortion. (:to.l%) Input source = 0 dBu. Connect Input to Channel 2 and adjust RVl4 for a reading of 0.5% Distortion. (:to.l%) Output = distortion. 4. GAIN. With the Input still connected to Channel 2 set the Output Level for +4.0 dBu using RV2. Input source = +4 dBu. Connect the Input to Channell, set the Output Level to +4.0 dBu using RVI. Output = dBu. Set the COMPRESSOR ON switch IN. Check value is +4.0 dBu (:!:O.3dBu). 5. THRESHOLD Set THRESHOLD and RAllO pots fully clockwise. Input source = -20 dBu. Set RV7 initially fully clockwise and note value, then slowly anti-clockwise until the Output Output = dBu. Value changes by 0.2 dBu. 6. METER CAL Set THRESHOLD and RATIO fully anti-clockwise. Input source = +4 dBu. Verify the Output Value is +4.00 dBu. Trim gain pot if necessary. Output = dBu. Adjust RV5 so the Meter is reading Zero dB. Set the METER switch IN. Adjust RV4 so Meter is reading Zero dB. Set THRESHOLD fully clockwise. Vary RATIO so the Output reads -2.00 dBu. Set RV3 so Meter is reading -6 dB THIS PROCEDURE IS INTENDED FOR USE BY A QUALIFIED TECHNICIAN ONLY. WARNING! ! ! HIGH VOLTAGES EXIST ON THE PCB. RadioFans.CN 收音机爱 好者资料库