Boss

GT-X Setup Manual page 116

Section 27 Factory Rest/Commissioning
5. MIDI IN/OUT Check
This appears to be a MIDI loopback style test. This is done
using a single MIDI cable in a simple connection from the
MIDI Out -> MIDI In.
If you have no MIDI cable connected, the display will read
'No Connect' and you may simply press [EXIT] to move on
to the next test. If you have a MIDI cable, simply connect in
to out. The test should produce 'Verify OK' if the MIDI
ports are OK.
6.Output D/A Converter Test
Be careful with this next test. Have your volume control
set FAIRLY LOW to avoid damaging anything!
suggest not having an amp connected at all for the next
few signal tests!
This test is designed to be done on an oscilloscope. A
rectangular waveform is applied to the input, and the GT-5
OUTPUT control is adjusted from 0-100% to verify level
changes. If you don't have an O-scope, you can connect the
GT-5 to your amplifier (with the volume starting at ZERO).
Slowly turn up the volume, you will hear something like a
500Hz tone being muted and un-muted...in time with the
Mute Off/On display in fact! If you haven't turned the
output level knob up do so now. Do it slowly and carefully.
On the other hand, if you've just parted with your speakers
and/or your eardrums, then turn it down. I told you so
(before we started!). When you are bored press [EXIT] to
move on.
7. DS A/D/A: Low Gain Check
This test is checking a complex analogue test signal that is
converted to digital, then back to analogue for comparison
using an Oscilloscope. [GAIN LOW] is displayed on the
display's bottom line. Press [EXIT] to continue.
8. DS A/D/A: High Gain Check
This test is checking a square wave analogue test signal that
is converted to digital, then back to analogue for
comparison using an Oscilloscope. [GAIN HIGH] is
displayed on the bottom line. Once again, press [EXIT] to
continue.
9. DS A/D/A:Overdrive Check
This test is checking a square wave analogue test signal that
is converted to digital, then back to analogue for
comparison using an Oscilloscope. This test is checking the
DS A/D D/A converters. [OVERDRIVE] is displayed on
the bottom line. Once again, press [EXIT] to continue.
© Copyright 2000-2002 Barry S. Pearce et al.
10. DS A/D/A:CV Check
This test is checking the DS Control Voltage test signal
using an Oscilloscope. [CV Check] is displayed on the
bottom followed by a control voltage number that scans up
and down. Once again, press [EXIT] to continue.
11. LOOP Check
This test checks a generated DSP signal to the SEND jack
of the LOOP. Again, this is designed to be done on an O-
scope showing a nice rectangular waveform output. When a
blank plug is inserted into the RETURN jack, the signal
should stop at the SEND Jack, and show up at the OUTPUT
(L) Jack. This verifies the cut-off function of the RETURN
I Jack. The display bottom line reads [DSP-> EXT -> OUT].
Once again, press [EXIT] to continue.
12. Noise (IN->OUT) Check
This test checks the residual noise of the I/O system with
the INPUT and OUTPUT levels at MAX. Using a noise
meter, connect to the OUTPUT Jacks (R, then L with a
blank plug in R), look for noise at –79DbM or better. Once
again, press [EXIT] to continue.
13. Noise (LOOP) Check
This test checks the residual noise with the LOOP system
converters engaged. Set the INPUT and OUTPUT levels at
MAX. Using a noise meter, connect to the OUTPUT Jacks.
Connect a cable between the LOOP SEND and RETURN
Jacks. Look for noise at –79DbM or better. Once again,
press [EXIT] to continue.
14. Noise (DS)
This test checks the residual noise of the DS system with the
INPUT and OUTPUT levels at MAX. Using a noise meter,
connect to the OUTPUT Jacks (R, then L with a blank plug
in R), look for noise at –71DbM or better. Once again, press
[EXIT] to continue.
15.INPUT A/D Check
This test is checking a square wave analogue test signal that
is input into the INPUT Jack, run through the ADC / DAC
process, then to the OUTPUT Jack for comparison using an
Oscilloscope. First the INPUT Level, then the OUTPUT
Level are slowly adjusted to show output level change on
the scope. [IN---- OUT] is displayed in the bottom line.
Once again press [EXIT] to continue.
16. DSP Pitch Interrupt Signal Test Check
An interrupt signal generated by IC9 on the board is
checked. It either passes or fails. The test quickly displays
'--- OK! ---' Once again press [EXIT] to continue.
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