158 Dual Sine/Sawtooth Oscillator
Two independent oscillators in one unit. Frequencies are continuously variable from 5 cps to 20 kc and may be controlled internally or with externally applied control voltages. Waveshape is continuously adjustable from sine to sawtooth; oscillators may be wideband frequency modulated.
Bill of Materials (value/qty)
- Resistors
- 1.0K x 4
- 10K x 8
- 150R x 2
- 15K x 2
- 1.5K x 16
- 150K x 2
- 220R x 2
- 2.2K x 10
- 2.2M x 2
- 3.3K x 16
- 33K x 2
- 330K x 4
- 47R x 2
- 470R x 4
- 4.7K x 8
- 6.8K x 10
- 2.2R, 1/2 Watt x 2
- 1.0K Trimpot x 6
- 50K audio taper pot x 4
- 10K linear pot x 2
- Capacitors
- 47pF x 2
- 22pF x 2
- 910pF x 4 (can sub 1nf)
- 4.7nF (polystyrene) x 2
- 47nF x 2
- 1uF x 2
- 15uF tantalum x 2
- 56uF tantalum x 4 (can sub 47uf)
- 47uF tantalum x 2
- Semiconductors*
- 1N457 x 6
- (MD708B) 2N5550 x 4
- (2N4916) 2N5401 x 12
- (2N3565) PN3565 x 14
- (U147) 2N5020 x 2
- (E101) J201 x 2
- Misc.
- .156" 4-pin power header x1
- DPDT Switch x
Errata/Notes
- *Transistor substitutions:
- Q1/Q2, NPN matched pair: MD708b is unobtainium - substitute 2n5550 (a matched pair of 2n3904 may also be used)
- Q3, Q5, Q6, Q12, Q13, Q14, 2N4916 PNP: technically obsolute but pretty easily available NOS; 2N5401 would be a recommended replacement (check pin-out)
- Q4, 2N3391 NPN: currently available from Mouser
- Q6, P-channel FET: U47 is unobtanium, substitute 2N5020
- Q4, Q8-Q11, Q16-18, 2N3565 NPN: currently available from Mouser as PN3565
- Some builders have substituted 2n3904 for all NPN and 2n3906 for all PNP transistors, across the board; I've not tried this yet myself.
- C6 was orginally a 5-35pf trimmer capacitor; substituted a fixed 22pf
- R35 was orginally a 3k3 fixed resistor; substituted a 5k variable resistor to trim signal feeding sine shaper (Mike Peake's suggestion)
- Some builders have changed R45 from 3k3 to 4k7, to modify sine waveform