Function Test; Starting Built-In Inspection Program - Zoom g9.2tt Service Manual

After the G9.2tt is assembled, the following inspections and settings should be made.
* Equipment required
· AC voltage meter (audio analyzer would be better)
· IHF-A filter (audio analyzer might include it)
· Oscillator
· AC adapter (AD-00012)
· Cables
● Set up before start up Test Mode.
* Adjust both [GAIN SW] (SW200) of OUTPUT and [GAIN SW] of EXT LOOP in -10 dBm.
* Adjust [OUTPUT LEVEL] (VR200) in MAX.
* Adjust both [TUBE] knob (VR201) of ENERGIZER and [BOOST] knob (VR202) of
ENERGIZER in 0 (turn counterclockwise extremely).
* Adjust [TUBE] knob (VR701) of ACCELERATOR in 5 (center) and [SOLIDSTATE] knob
(VR703) of ACCELERATOR in 5 (center).

1. Starting built-in inspection program.

Connect the AC-adapter.
(1)Turn on the "Power SW" while holding [AMP SELECT SYSTEM] key(SW5) and [EXIT]
key(SW19).
Or TP1 of the main PCB connect to the GND before power on. And then power will be turn on, the
set is running as Test Mode.
*AC adapter must be used AD-0012.
(2)After turning on the power, 7SEG LED will be displayed as [8.8.] and LCD, all of the SW, LED
will be ON.
*There is no sound comes out from OUTPUT in this status.
*To make sure that there is no broken or any no dark LED was found.
*After power turned on, the tube will be warm and bright.
(3)When any key will be pressed, the system will be start to DSP Download test mode.
This is the test for Test mode program downloading to the DSP.
This test methodology is comparing with the data which was written and the data which was read.
If in the case of successfully, LCD will be displayed as [DSP DOWNLOAD OK].
If in the case of fail, LCD will be displayed as [DSP DOWNLOAD NG]. If in this case all of the
testing after that will be ignored.
After holding display for 1sec, the LCD comes up all segments again, and then DSP can do a
signal processing.
(De-Emphasis and Emphasis circuit are working in this status.)
*After this the sound which is added from [INPUT] and [AUX IN] comes out from all [OUTPUT ]
(PHONE, L/MONO, R terminal).
When any key will be pressed, all LCD and LED will be off and then the system will be into
another test mode.

Function Test

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