TubeOhm SMR4P User manual

29.08.2018
TubeOhm SMR4P-multi VCF
DIY manual
© 2017 by TubeOhm
1

SMR4P- multi VCF a embly guide V 1.03
TubeOhm
technical pecification :
•multimode 4 pole filter
•20 Hz.. 22kHz (res 24dB)
•max signal amp input 5 p
•resonance control intern/ext. 0..10 v
•cutoff control intern/ext 0..10v /OCT
•modulation ext. 0..10 v
•inbuild filter FM
•inbuild CA , ext. control 0..10 v
•15 filtermodes available ,6+12+18+24dB LP, 6+12+18 dB HP, 6+12 dB BP, HP2LP,
HP3LP,Notch,Phaser, Notch+LP1, Phaser+LP1. oltage controlled 0..10
•Current 30 mA on -12 , 50 mA on + 12
•Dimensions : 50,5mmx128,5mm = 10TEx3HE eurorack format
•power +/- 12 olt
Schematic and BOM
The BOM and the schematics can be found on TubeOhm.com
2

1:) Prepare the PCB
Separate the PCB in three parts . Simply break the PCB into 3 peaces and cut with a
cutter the little rest on the top and back of the PCB.
break it into three peaces
3

cut the rest with a cutter
smooth it with a file
4

1 2 3
Now we have three PCB'
1) the Pannel Board V 1.03 for the pots, LED's, plugs
2) the Control Board V 1.03 for the CPU,and the pole mixing
3) the Analog board V 1.03 the complete filter board
Let u tart with the analoge board V 1.03
first we solder all resistors and coils - diode
second all caps
third the IC sockets and transistors / power regulators
forth the headers and pin connectors
5

we start with R 59 = 68ohm
Image Description Quantit Notes
68 ohm 1
Blue, gray, black, gold brown
R59
than 5 x 220 ohm
Image Description Quantit Notes
220 ohm 5
Red,red,black,black, brown
R18,29,31,39,72
6

2x 1k ohm
Image Description Quantit Notes
1k ohm 2
Brown,black,black,brown,brown
R19,58
3x2,2k ohm
Image Description Quantit Notes
2,2k ohm 3
Red,red,black,brown,brown
R23,65,71
7

12x 10k ohm
Image Description Quantit Notes
10k ohm 12
Brown,red,black,black,brown
R16,17,27,28,30,32,34,35,36,37,55,63
1x 12k ohm
Image Description Quantit Notes
12k ohm 1
Brown,red,black,red,brown
R 2
8

2x 15k ohm
Image Description Quantit Notes
15k ohm 2
Brown,green,black,red,brown
R 21,38
3x22k ohm
Image Description Quantit Notes
22k ohm 3
Red,red,black,red.brown
R 20,57,67
9

1x 33k ohm
Image Description Quantit Notes
33k ohm 1
Orange,orange,black,red,brown
R13
1x47k ohm
Image Description Quantit Notes
47k ohm 1
Yellow,purple,black,red,brown
R14
10