Hammond Organ L-100 Series, Руководство по обслуживанию

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Page 29
4–1 GENERAL
This section contains performance standards, adjustment
procedures, and troubleshooting information.
NOTE 4–1–A
Before making any checks or adjustments involving amplifiers, test all
tubes to ensure they are operating properly.
4–2 ORGAN PERFORMANCE CHECK
To prepare the organ for performance check, proceed according to
the following:
a. Place all tabs in up (off) position.
b. Push drawbars into limit of motion.
c. Set swell pedal for maximum output.
d. Connect meter to speaker terminals.
NOTE 4–2–A
At certain steps in the following procedure, conditions other than
above may be specified. Return controls to above conditions as each
step is completed.
NOTE 4–2–B
Drawbars, pedals, and keys are called out by number, beginning with
No. 1, at left end of row.
4–3 EQUIPMENT REQUIRED
a. VTVM, Commander 870 or equivalent.
b. Oscilloscope, Tektronix 503 or equivalent.
4–4 PROCEDURE
a. Depress UPPER DRAWBARS tab and pull drawbar No. 1 to
position 8. Play lowest C on upper manual (Frequency 25),
and observe meter. If output is not between 1.6V and 2V rms,
adjust GAIN ADJUST on power amplifier to bring output into
range.
b. Maintain conditions of step a. Depress VOLUME SOFT tab.
Output should drop to range of 0.69 to 0.9 volts rms.
c. Set pedal drawbar at position 8. Depress lowest C pedal.
Output should be between 4V and 5.5V rms.
NOTE 4–4–A
If output is not within specified range, select R1, Figures 5-1 through
5-4, from 1.8
Ω
to 27
Ω
to bring output into range.
d. Maintain conditions of step c. Depress VOLUME SOFT tab.
Output should drop to 0.8V to 1.5V rms.
e. Return VOLUME SOFT tab to “up” position. Maintain
other conditions of step c. Play all pedals to be sure output
changes smoothly from note to note.
f. Make upper manual preset listening check. Hold down F, A,
C chord near center of upper manual.
1. Trumpet. Set up upper drawbars to 006688888. Press
SECTION IV
PRACTICAL SERVICE SUGGESTIONS