[Alt-photo] 365 nm. UV-Densitometer. Part 1a of 7

[Erich Camerling]

The power supply  (Part 1)

This supply  delivers  the  power  for the clock factory ,
LED-driver ,
sensor ,
reverse circuit and
                                                                 DVM .
The input is an alternating voltage from a trafo with a middle-branch : 
2 x 12  V  5 VA
The output is a flattened  + 14 V , not stabilized , for the input 
voltage to the sensor and the reverse circuit ,
                        a flattened  - 14 V , not stabilized , for the 
input voltage to the sensor and the reverse circuit ,
                      a stabilized  + 10 V  for the LED-driver ,
                      a stabilized  +  5 V   for the clock factory and 
the DVM  and
                      a stabilized  -  5 V   for the DVM .
However :  the  + 5 V is determining for the amplitude from the 10 msec 
pulse from  the
clock factory and with that determining the current through the UV-LED . 
For that reason
the 78L05 receives a stabilized  + 10 V. And sensing is meaningful in 
this situation !.
We assume that the UV-LED driver will use 60 mA average , the clock 
factory 3 mA ,
the sensor circuit 8 mA and the DVM  x mA  (depends on which supply is 
used : LCD
or LED)

Part list :
78L05 , 79L05 , 7810
4x Diode>= 2 A  (e.g. BYV27 , 1N 5060  etc.)
C1 , C3 , C8  = 0.47 µF / 63 V
C2 , C4 , C9  = 0.1   µF / 63 V
C5 = 1000 µF / 35 V
C6 =   470 µF / 25 V
C7 = 1000 µF / 25 V
R2 =  158 Ohm
5x  5.08 mm. pitch screw terminals 3 pins ( from www.te.com . No: 
1776119-3    or an other supplier )

To be continued next week.

PS. May be the solution for attachments : when you  are really interested ,
        send your e-mail address to my personal e-mail address and I 
will send you
        the attachments going with the different chapters.