USL JSD-80 Manual - Manual (Page 24)

USL, Inc. JSD-80 Instruction Manual Page 24 3rd Edition. February, 2006
Connect the shielding of the cable to
the Chassis terminal (pin 3). Do not
connect the shielding at the projec-
tor end. The D-9 connector should be
plugged into the Projector 1 input of
the JSD-80.
3. Film readers with active circuits, such
as a Jaxlight line amplifi er or a reverse
scan reader, will require a ground con-
nection at the reader. Good results can
be achieved using the drain (shield)
wire of the cables listed above, how-
ever, some agencies (such as CE)
prohibit using the drain conductor
for this purpose. In that case, use two
3-conductor shielded cables (such as
Belden Nº 9939) (see Section 6.1).
4. If there are two projectors, the change-
over is accomplished by grounding the
“X-OVER” terminal. Connect a latching
relay, with the appropriate rating, so
that one coil is powered by the dowser
circuit of Projector 1 and the other
coil is powered by the dowser circuit
of Projector 2. The relay contacts
must be connected to the “XO” and
“COM” terminals so that the contacts
are closed when Projector 2 is opera-
tional.
5. Set the JSD-80 preamp controls so
the gain is at the midpoint and the
high frequency boost fi lters are at the
maximum frequency (32 kHz). This can
be accomplished from the JSD Laptop
Interface Software. Connect a dual
trace oscilloscope to the test points
on the JSD-80 “Input Module” board.
“Left” is RED, “Right” is GREEN, and
“GND” (Audio ground) is BLACK. Run
a 100% alternating left/right STEREO
ALIGNMENT fi lm and move the cell
in and out until the crosstalk is at a
minimum on both channels as shown.
It may be necessary to set the gain of
the preamp roughly at this time.
6. Run a 50% level fi lm such as the Cat
69T or equivalent. Adjust the Left and
Right level controls on Projector 1
until the preamp calibration LEDs on
the input screen show two green indi-
cator lights. Repeat the procedure for
Projector 2 if applicable.
7. Double check the cell alignment by
running a 100% STEREO ALIGNMENT
fi lm. The amplitude of the two 100%
modulated waveforms should be iden-
tical (see illustration). If one is greater
than the other, while the modulated
waveforms of the 50% level fi lm are
identical, there is a problem with the
scanning beam. Either the slit is not
uniformly illuminated along its length,
or the scanning beam is not in perfect
alignment with the fi lm guide roller
and solar cell. Since most soundhead
optics cannot be moved in or out, it