Service Manual ProTone
Page 2 of 20
© 1996-2001 Spectral Audio
1
Description of the Operating Elements
3
1.1
Sockets on the Rear of the Housing
3
1.2
Front Panel Controls
4
2
Functional Description
5
3
History of Series
7
4
Improvements and explanations
7
4.1
Sense of R174 and R175
7
4.2
Sense of C63 – C65
7
4.3
Sense of R174 and R175
8
4.4
Hum Problems
8
4.5
Increasing the Gate voltage to +12V
8
5
Adjustment of the ProTone
9
5.1
Digital PCB (MIDI to CV converter)
9
5.2
Analog PCB (VCO1 and VCO 2)
9
5.2.1
VCO1
9
5.2.2
VCO2
9
6
Digital PCB
11
6.1
Assembly plan
11
6.2
Part list
11
7
Analog PCB
13
7.1
Assembly plan
13
7.2
Part list
15
8
Mechanical part list
20
