Lexicon PCM 42 - Page 6

N. DELAY DISPLAY
When the SET-MODE switch is in the DELAY posi-
tion, the DELAY DISPLAY gives a precise 4-digit
display of the actual Gelars ime in milliseconds. With the
SET-MODE switch at CLOCK, it shows display of the
clo ae eee {see seca K above). The delay time
disp is accurate and updates itself very quickly,
stewines it to track all sweep functions as fast as the eye
can follow.
O. CLK LED
The CLK LED flashes in synchrony with the CLOCK
UTPUT on the rear panel. The rate at which the la amp
he is determined by the fraction programmed v os
SET-MODE, DOWN and UP, coupled with the settin
of the VCO-SWEEP controls.
To determine the exact period of the CLOCK, step
the delay tap value upward with UP until the display
ceases to increment, indicating maximum delay time.
(Use the fast-forward function described in paragraphs
K and L.) Note the delay time, and then switch SET-
MODE to CLOCK and read the display as a fraction,
with the numerator on the left and the denominator on
the right. The clock period is equal to the delay time
times the clock fraction. Note that if DEPTH is not set to
QO, or an external modulation is present, the clock rate
will not be stable.
P. co LED
The INFINITY LED is illuminated whenever the repeat
mode is selected by the INFINITE RPT pushbutton or
the corresponding footswitch jack.
Q. 6 kHz LED
The 6 kHz LED lights when the long delay mode is
selected by DELAY X2, indicating a reduction in band-
width to 6 kHz and a doubling of the available range of
delay.
R. MANUAL VCO-SWEEP
The MANUAL VCO-SWEEP control provides con-
tinuous, smooth control of delay times over a range of 3
to 1 by modifying the sampling rate. This control func-
tions as a,manual modulation for flange, chorus and
pitch twisting effects, and for access to very long delay
times.
S. DEPTH
The DEPTH control adjusts the amount of internal
modulation of the VCO, affecting the depth of sweep
r or flange, chorus and pitch-twisting. When DEPTH is
set at “O"', the internal sweep Is inactive. As the DEPTH
control
.
advanced
clockwise
toward
‘'10",
the
range
of the sweep increases to a maximum clock ratio of 3:1.
The DEPTH control interacts with the MANUAL
¥CO-SWEEP control (Fig. 2.1-R). The MANUAL con-
trol has its maximum effect with the DEPTH at 0", and
no effect with the DEPTH control at 10".
T. WAVEFORM
The WAVEFORM control selects the
modulation:
type of VCO
1. Full counterclockwise rotation selects sinusoidal
modulation: the delay time smoothly increases
and decreases at a speed governed by the RATE
setting.
2. Setting the control at the center detent selects
envelope-follower modulation: the delay time
changes in response to the level of the input
signal.
3. Full clockwise rotation selects square-wave
modulation: the delay time jumps instantaneously
up and down according to the setting of the RATE
control.
4. Intermediate positions of the control blend either
sinusoidal or square-wave modulation with
envelope-follower modulation.
U. RATE
The RATE control adjusts the low-frequency
oscillator (LFO) that controls the frequency of the sine-
or square-wave modulation. With the WAVEFORM
control in the center (envelope-follower) position, the
RATE control will have no effect.
V. RATE LED
The RATE LED flashes on and off to indicate the rate
of the LFO and to allow playing in synchronization with
the delay sweep.
W. POWER SWITCH
This latching pushbutton turns the AC power on and
off. On power-up, the delay time is automatically set to
O ms, the infinite-repeat function is turned OFF, and the
clock ratio is set to a value of 1/2. All other switch and
control settings remain as they had previously been set.