Kit 106. 50 Watt Audio Amplifier
Page
3
of
5
Circuit Diagram
* Please note C6 is shown incorrectly on the
PCB overlay. The circuit diagram is correct.
Suggested Power supply circuit
+
Input
13
Speaker
(not included)
+
_
+
+
+
+
+
C1
1u5
Negative
24 - 36V
DC
IC1
TDA 7294
2200uF
25V
C9
2200 uF
25V
C8
100nF
C10
100nF
C7
+
Gnd
22uF
63V
C6
10k log Pot
Input
Attenuator
(Not Included)
.
7
R1
150R
R2
10k
C2
2n7
1
8
15
R3
10k
R4
680R
3
4
14
6
Positive
24 - 36V
DC
C3
22uF
63V
2
DC
Gnd
R5
10k
R6
22k
Mute
Standby
10
9
C4
10uF
63V
C5
10 uF
63V
Output
(optional)
.
For a stereo pair you may double the VA of the transformer, diode bridge current,
increase capacitance and fuse rating.
Alternatively use two complete supplies.
A
N
E
Fuse
Switch 1a
Switch 1b
4* Diodes 5A/200V
or Diode Bridge
Mains
I/P
4700uF
50V
4700uF
50V
+
+
_
+
Gnd
35V
35V
Transformer
50V 80VA
centre tapped
.
.
2-3A
* All grounds must connect at the same point
(+/- 25V AC)