A P P E N D I X
Appendix I: Quick Reference - Summary of indicators
Indicators and displays
:
Off
: No display
Standby, not ready for power up
: Slow flashing ----, relevant red LEDbar and relevant diagnostic LED lit (see
Fault section)
Standby, ready for power up
: Steady ---- with no other lights lit
Triode mode
: Red MODE light
Tetrode Mode
: Green MODE light
Power up
: Blinking blue POWER light, 240 to 000 countdown on display (if not suppressed) with MUTE light
flashing. Steady 000 (if not suppressed) and flashing blue POWER light if biasing not yet completed, and MUTE
light blinking
Power on
: Steady blue POWER light
Muted
: Steady red MUTE light
Unmuting
: Blinking red MUTE light
Tube Biasing
: Steady or Flickering green light (if not suppressed) on top deck next to each tube.
Tube not biasing
: All top deck tube lights off, indicating amp is receiving signal.
Phase inverted
: Steady red INVERT lighted text
Non-critical tube fault
: Steady green TUBE lighted text, relevant tube number (01 to 12) on display, slow
blinking green LED on top deck by tube corresponding to number on display, tube light turned off for
corresponding tube on other phase biased to cutoff.
Critical tube fault
: Slow flashing red TUBE lighted text, relevant tube number (01 to 12) on display, fast
blinking green light on top deck by tube corresponding to number on display.
Overheat
: Slow flashing red HEAT lighted text and flashing ---- display to show re-power not allowed until safe
temperature reached. (HEAT text extinguished and steady ---- when temperature drops to safe level, to indicate
re-power allowed)
Power supply faults
: Slow flashing red POWER lighted text on front panel, and relevant display
•
AC power supply fault
: Incorrect AC voltage (low or high): Alternately flashing AC voltage setting and
---- to indicate power up not available until correct voltage sensed.
Regulator fault modes
:
•
OC
(over current) (Plate or Screen) Flashing red POWER lighted text and steady ----, to indicate
immediate re-power available.
•
OV
(over voltage) Slow flashing red POWER lighted text and ----, with re-power not allowed until
technician re-set after repair.
•
Regulator current shift fault
: Steady red POWER lighted text as regulator drops out of current shift
and immediate shutdown, and slow flashing red POWER lighted text and steady ---- when shut down to
indicate immediate re-power available.
Diagnostic LEDs
:
•
Total Time
(Operate or standby modes): Not re-settable. Press to show total amp on time.
•
Tube time
(Operate or standby modes): Press to show tube time. Reset with retube by holding down
TUBE TIME and RESET buttons for 15 seconds until clear response (--) from display.
•
Service Reminder
Green TUBE led bar and TUBE TIME led after every 3000 hours of TUBE TIME
,
at each successive 3000 hour interval to remind the user to check the tubes and re-tube if necessary.
•
AC voltage display
: (Operate mode) Press to show AC voltage at supply. (Standby mode: Press to see
pre-defined AC voltage setting in EEPROM)
•
Bias display
(Operate mode only): Press to show bias setting for each tube. Top deck led flashes super
fast and tube number (01 to 12) shows on display to identify tube. Bias readout then shows on display
for 2 seconds. The bias button led comes on when the bias button is pressed.
S-400 Amplifier Owner’s Manual
VTL
58
