Internal Adjustments - Shure M367 User Manual

Only qualified service technicians
should perform these modifications.
These internal adjustments require only removal of the top
cover:
1.Remove battery compartment.
2.Remove four screws securing two plastic end caps and one
ground–bonding screw on the side opposite the battery compart-
ment.
3.Slowly slide cover up and off chassis.
VCA DISTORTION TRIMPOT (R607)
DO NOT ADJUST! This potentiometer is precisely calibrated on
each mixer for minimum distortion.
VU METER ADJUSTMENT (R684)
This trimpot adjusts the VU meter to indicate 0 VU at a preset out-
put level. The factory setting is +4 dBm. The user adjustment range
is –10 dBV to +4 dBm (–6 dBV to +8 dBm with DIP switch 1 down).
To set the VU meter to a value other than the factory setting
(0 VU = +4 dBm), proceed as follows:
1.Connect a 600 Ω load to an XLR output set for Line.
2.Connect an ac voltmeter with 1 MΩ or greater input impedance
(Fluke 77 or equivalent) in parallel with the load.
3.Set the 1 kHz tone oscillator switch to the ON position.

INTERNAL ADJUSTMENTS

WARNING
4.Adjust the 1 kHz tone oscillator level with the Master gain
control until the ac voltmeter reading is at the level desired.
5.With the M367 top cover removed, adjust the VU Level
Calibration trim pot R684 with a screwdriver until the VU Meter
reads 0.
6.For 0 VU settings between +4 and +8 dBm, set internal DIP
switch S701 position 1 "down", and perform steps 1 through 5.
VU METER
CALIBRATION
TRIMPOT
R684
(ACCESSED
THROUGH
HOLE IN
UPPER FRONT
PC BOARD)
INTERNAL ADJUSTMENTS
FIGURE 8
VCA
DISTORTION
TRIMPOT
R607
DIP SWITCH
S701
7