Yamaha R S300, Service Manual

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R-S300
R-S30
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4. AD DATA
This menu is used to display the A/D conversion value of the microprocessor which detects panel keys and protection
functions by using the sub-menu.
When “4-3. KEY 0/KEY 1” sub-menu is selected, keys become non-operable due to detection of the values of all keys.
However, it is possible to advance to the next sub-menu by turning the “INPUT” knob.
*
Numeric values in the figure are given as reference only.
4-1. PS/DC
PS: Power supply voltage protection detection
The voltage at 93 pin (PRV) of the IC502 is displayed.
Voltage detects:
PS: ACL, AC15, ±15, +5S, +15UNREG (R model)
Normal value:
PS: 36 to 77 (Reference voltage: 5.0 V=255)
*
If PS becomes out of the normal value range, the protection function works to turn off the power.
DC: Power amplifier DC (DC voltage) output is detected.
The voltage at 89 pin (PRD) of the IC502 is displayed.
Normal value: 48 to 128 (Reference voltage: 5.0 V=255)
*
If DC becomes out of the normal value range, the protection function works to turn off the power.
P S : 0 5 7 D C : 0 9 0
3 . P R E S E T I N H I
3 . P R E S E T R S R V
3. FACTORY PRESET
This menu is used to reserve/inhibit initialization of the back-up IC (EEPROM: IC503 on FUNCTION P.C.B.).
3-1. PRESET INHIBIT (Initialization inhibited)
Initialization of the back- u p IC is not exec u ted. Select this s u b-men u to protect the val u es set by the u ser.
3-2. PRESET RESERVED (Initialization reserved)
Initialization of the back- u p IC is reserved. (Act u al initialization is exec u ted the next time the power is
t u rned on.) To reset to the original factory settings or to reset the back u p IC, select this s u b-men u and
press the “ ” (Power) key to t u rn off the power.
CAUTION: Before setting to the PRESET RESERVED, write down the existing preset memory content of the tuner. (This is
because setting to the PRESET RESERVED will cause the user memory content to be erased.)