760A / 760D / 760N 5–1
Section 5Performance Check and Calibration ProceduresThis section of the manual consists of two procedures. The Performance Check
procedure is a guide to verifying warranted specifications of the 760A, while the
Adjustment procedure, when properly performed, will result in a 760A that
performs as warranted in SECTION 1, INTRODUCTION AND SPECIFICATION.
Throughout both procedures, all 760A front– and rear–panel nomenclature is
fully capitalized, (e.g., DISPLAY GAIN). All 760A internal adjustment and
jumper names have only the first letter capitalized, (e.g., Geometry).
The following list of test equipment and requirements are the minimum
necessary to perform the Performance Check and Adjustment procedures. The
specific test gear that was used to develop this procedure is listed in parenthesis
after each generic test equipment name.
1. Leveled Audio Frequency Signal Generator
(TEKTRONIX SG 505 Opt. 2)
Balanced Output 50Ω impedance
Frequency Range 20 Hz to 20 kHz
Output Level Range 3.5 mVrms to 4.89 Vrms
Frequency Response "0.1 dB from 20 Hz to 20 kHz (1 kHz reference)
2. RMS Voltmeter
(TEKTRONIX DM 501A)
Accuracy: "2% of reading, 20 Hz to 20 kHz.
3. Digital Volt/Ohm meter
(TEKTRONIX DM 501A)
Dc Accuracy: "0.5% of reading, –12 V to +12 V.
4. Test Oscilloscope with Differential Comparator, with two X1 probes.
Adjustment procedure only
(TEKTRONIX 7704 w/7A13)
Common–Mode Rejection: 1000:1
5. Variable Autotransformer
(General Radio Metered Auto Transformer W10MT3W)
If 220 volt operation must be checked, a conversion transformer or
appropriate 220 volt autotransformer is needed.
6. Male XLR adapter cables (3)
Manufacture three cables that will interconnect the 760A rear–panel XLR
connectors with the Leveled and Second Audio Signal Generator outputs.
XLR pin 1 = Gnd
XLR pin 2 = +
XLR pin 3 = –
Introduction