Luxman CL 35 mk III - Time Delay Circuit; Time Delay Circuit Operation

r---~--O+6. 52V
fig.-ll
lN4002
" 1
input
6.52V
IN4002
rms
0
~
~
The circuit is shown by Fig. 11. Power supply section is common to headphone amp and pilot lamp.
Q212 is put into operation the instant the power is switched on. As to Q213 bias is gradually
given on the base through R231 and C215. To activate it some 0.4V is needed. When the power
supply is 100% 0.4V equals 6%. To charge 6%, T/CR is needed by 6% which corresponds to 24 sec.
(CR =400uF.Kohms).
Q211
is activated when Q213 is turned on, and relay functions to break allowing the Pre Out
terminal to be open from short-circuiting.
Q2l2 is turned off the instant the power is switched off, and then Q2l3 and Q2l1 are turned off
to let the relay.contact make and short-circuited.
Thenafter the base current of Q2l3 is supplied by D204.
PB-667
"
4