Kobol Clone
Projecttitel: RSF KOBOL Clone
Status: FINISHED
Startdate: 01/2019
Duedate: 02/2020
Updated: 02/2023
Manufacture link: deliandiver.com
https://www.muffwiggler.com/forum/viewtopic.php?t=203509&highlight=
Summary:
works, but its not for beginners and until the developer do not change the PSU from Main AC to Walwart psu its definitely not for beginners.
you need 2x SSM2050 or use 2055/2056 with a mod.
This documentation is only for myself, to have some notes about changes and mods
This PCB which I used isn't available anymore !!
Theres no support available and much knowledge needed.
Sync sounds:
Backup from Crazy.P incl. SSM.-SSI adapter pinout
ISSUES
Nr. | Description | Priority | Solution | |
---|---|---|---|---|
1 | Switches - use other pcbs footprint size and/or change panel to toggle switch | 1 | ||
2 | BOM : LOG for Volume LFO and VP out gain | 3 | fixed | |
3 | missing mounting holes for pcbs | 2 | open | |
4 | LED driver needed for gate led | 2 | fixed | |
5 | leds polarity on pcb | 3 | fixed ? | |
6 | LFO speed inverted pot, left is fast on the prototype | 1 | Or use reveresed Poti | fixed |
7 | panel holes too big for potis | 1 | open | |
8 | powersupply design not allowed - | 2 | open - use a own PSU - Yamaha PA30 and resctifier, capactitors | |
9 | markers for voltage test points missing | 3 | open | |
10 | more clearly infos about matched trannys and resistors | 3 | ||
11 | envelope change too CEM3310 or digital | 1 | open | |
12 | capacitors are too close next to the power supply section on mainboard | 1 | fixed | |
13 | use bigger traces | 1 | open | |
14 | Gate signal bleed in LFO | 1 | Blocker | fixed |
15 | V/oct unstable - waveforms wobbling - | 1 | Blocker | fixed |
16 | Lfo led not working | 3 | fixed | |
17 | Holes in vcf board and VCO board to mount on metal spacers - for better mounting | 2 | open | |
18 | Case doesn't fit with the panel | 1 | workaround possible | |
19 | ua726 | 1 | use normal matched pair trannys | |
20 | ssm2040 | 1 | use the new SSI 2040 !! | |
21 | ||||
22 | knobs ask Patrick_H | |||
23 | connector 2pin | 13x | JST XH2 | https://www.reichelt.de/jst-stiftleiste-gerade-1x2-polig-xh-jst-xh2p-st-p185073.html?search=jst+st |
24 | connector plug 2pin | 13 | JST plug | |
25 | pin connector | 26x for 2 pin 2x 3pin | JST | |
26 | connector 3pin | 2 | JST | |
27 | connector plug 3pin | 2 | JST | https://www.reichelt.de/jst-buchsengehaeuse-1x3-polig-xh-jst-xh3p-bu-p185086.html?search=JST+XH |
BOM: 11-2020
changes:
in crazy.p clone R135 ---> 68pF
in Crazy.p clone R207 ---> 22nF
Panel Wiring 11-2020
Project schematics RSF Kobol Expander I Clone.pdf
please note the 3Pin Connectors are wrong in the Wiring guide !!
Ground is the middle pin on the 3Pole connectors.
for all jacks:
S is to be connected on TIP Pin (hot)
SW is the Tip Switch Pin (for grounding when no plug is in the jack inserted)
Switches
needed: 1x 2 rows with 3 pins (ON/OFF) power (DPST)
mouser | RS | ||
---|---|---|---|
power | SSSU022800 | ||
4x normal | SSSU015100 |
or:
mouser | ordered | ||
---|---|---|---|
power | MHS222K not avail. | 06-MHS22204 | |
4x normal | MHS122K apem | home stock | |
Nr | ||||
---|---|---|---|---|
Pots | 50€ thonk T18 shaft or round shaft- you need 2 center pots and 1-2 Log 100KB 2xx 100kA 100KB center detent for tune and vco2 beat optional for Freq. its up to you. look at crazy patroches pic and in the BOM | |||
jacks | 45€ | |||
resistors | 30 | |||
capacitors | 2,2MF | reichelt | 5euro | |
ICs: 3080, lm324, lmxxx | estimated 100€ | |||
trannys, Power reg. | 5 | |||
diodes | 2 | |||
switches mouser | 10-20 | |||
cable and headers | 20 | |||
SSM2050 | 2x | 480€ or ask me for a replacement VCA/ADSR PCB to use CEM3310/AS3310 | ||
heatsinks | 2x | 5 | ||
external Yamaha PA30 | 50€ | |||
SSM2040 | Ebay 50 or use new SSI2140 with adapter 10€ | |||
case | Buchla boat from SAMODULAR - cut the frame to make it fit 100€ | |||
ic sockets | 10-15€ | |||
Yamaha PA-20 powersupply | 40€ | |||
knobs tme | GWB19BK | |||
LEDS | 3x | red | ||
Calibration
VCO: linearity = High Freq. compensation. = there's a 1Mega Resistor which is connect to the Trimmer - adjust the Trimmer as close to 0V (which is a OFFSET and affect the V/Oct calibration)
2. VCO 1V/Oct as normal with Guitar tuner method or Freq. Counter/DMM
Schematics:
ob_345da9_schemas-carte-kobol-expander-1.pdf
MODS:
from http://www.crazy-patroche.com/2017/07/etude-des-racks-rsf-expander-1.html
in case of the SSM2050 (2x needed)
you can use SSM2055/56 with changes
https://oshpark.com/shared_projects/N9Tw7FAP
or by hand wiring
Pin 2 to GND not shown - importend
Final Pictures:
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Related content
how to bugfix: https://diysynth.wiki.dsl-man.de/wiki/spaces/SKM/pages/336101402/How+to+bugfix
non commercial pages, all infos are best can do without warranty, without liability.