Honda CX500 1978 Shop Manual page 243

HONDA
TECHNICAL FEATURES
PULSER WAVE FORMS AND SCR PULSER WAVE FORMSWHEN ADVANCE
TRIGGER VOLTAGE BEFORE ADVANCE STARTS
Before advance starts, only the signal from the fixed
The voltage of the advance pulser rises t o SCR trigger
pulser is applied t o SCR gate through the diode D3. voltage faster than that of the fixed pulser. If there is
an increase in engine speed, there will be a correspond-
ing advance in timing.
SIGNAL FROM
FIXED PULSER
(THROUGH D2)
SIGNAL FROM FIXED
PULSER (THROUGH D3)
-
PULSER WAVE FORMS DURING TIMING
ADVANCE
M
SIGNAL FROM ADVANCE PULSER
PULSER WAVE FORMS AT END OF
ADVANCE
With further increases in engine speed, a transition The negative pulse from the fixed pulser balances the
occurs in the wave form, such as from A t o B. That is, positive pulse from the advance pulser, causing the
SCR is triggered sooner t o advance the ignition timing.
timing t o stop advancing.
COMBINED SIGNAL
OF ADVANCE
AND FIXED PULSER
/
SIGNAL FROM
SCR TRIGGER
VOLTAGE
ADVANCER PULSER
SIGNAL FROM
4
-
TIME
FIXED PULSER
Date of Issue: January, 1978
OHONDA MOTOR CO., LTD.
19-7