Enclosure not stated · 3 knobs
Multivox / Big Jam SE-4 Octave BoxVerified
Based on the Multivox / Big Jam SE-4 Octave Box
From the post
A pretty cool variation of MXR Blue Box with a few extra bits and features. The only thing that is a bit unclear is the switch that selects between one octave down, 1/2 octave down and 2 octave down. Original has a 3 position slider switch but I would like to convert to a toggle switch (3PDT on/off/on or DPDT on/on/on?) or maybe a rotary but I'm not sure how to tackle it. Layout has the switch labels per the schematic which can be found in this link: https://music-electronics-forum.com/filedata/fetch?id=829397 *update*7mike_p found a solution for the switch. See hit comment below.
Schematic
This is a board layout, a drawing of where each part goes, and the post may link the schematic it was drawn from. Open the layout at Dirtbox Layouts. No KiCad fragment has been drawn for this circuit yet.
Parts list 32 rows
Report a wrong parseGot parts in a drawer? See what you can build with them.
Check before you build · 3 values the reader of this layout was not sure of
- Q3 and Q4 (top of board): drawn and labelled but the legend lists only 'Q1-Q2: 2N5088,2N3904 etc.', which probably means Q1-Q4
- 33uF electrolytic at column 8, rows V-W: text partly hidden by the can's stripe, read as 33uF; printed clearly enough, unusual value
- Switch: legend itself says '3PDT on/off/on?'
| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 9 | ||||
| ×6 | 100K | 100k | read from the layout by eye | |
| ×6 | 56K | 56k | read from the layout by eye | |
| ×6 | 10K | 10k | read from the layout by eye | |
| ×5 | 1M | 1M | read from the layout by eye | |
| ×2 | 27K | 27k | read from the layout by eye | |
| ×2 | 680Ω | 680 | read from the layout by eye | |
| ×1 | 47K | 47k | read from the layout by eye | |
| ×1 | 470K | 470k | read from the layout by eye | |
| ×1 | 33K | 33k | read from the layout by eye | |
| Capacitors 10 | ||||
| ×3 | 10nF | 10n | read from the layout by eye | |
| ×2 | 33nF | 33n | read from the layout by eye | |
| ×1 | 15nF | 15n | read from the layout by eye | |
| ×1 | 22nF | 22n | read from the layout by eye | |
| ×1 | 220nF | 220n | read from the layout by eye | |
| ×1 | 680pF | 680p | read from the layout by eye | |
| ×4 | 1uF | 1u | electrolytic; read from the layout by eye | |
| ×1 | 10uF | 10u | electrolytic; read from the layout by eye | |
| ×1 | 33uF | 33u | electrolytic; read from the layout by eye | |
| ×1 | 100uF | 100u | electrolytic; read from the layout by eye | |
| Diodes 3 | ||||
| ×2 | 1N60 | 1N60 | D1, D2; read from the layout by eye | |
| ×2 | 1N4148 | 1N4148 | D3, D4; legend: 1N4148/1N914, 1S2473 in original; read from the layout by eye | |
| D5 | 1N5817 | 1N5817 | read from the layout by eye | |
| Transistors 4 | ||||
| Q1 | 2N5088 | 2N5088 | legend: 2N5088, 2N3904 etc.; 2SC945-Q in original; read from the layout by eye | |
| Q2 | 2N5088 | 2N5088 | legend: 2N5088, 2N3904 etc.; 2SC945-Q in original; read from the layout by eye | |
| Q3 | ? | ? | value not given; legend lists only Q1-Q2 (2N5088, 2N3904 etc.); read from the layout by eye | |
| Q4 | ? | ? | value not given; legend lists only Q1-Q2 (2N5088, 2N3904 etc.); read from the layout by eye | |
| ICs 2 | ||||
| IC1 | 4558 | 4558 | read from the layout by eye | |
| IC2 | CD4013 | CD4013 | read from the layout by eye | |
| Potentiometers 3 | ||||
| Tone | A50K | A50k | Potentiometer | read from the layout by eye |
| Balance | B50K | B50k | Potentiometer | read from the layout by eye |
| Level | B50K | B50k | Potentiometer | read from the layout by eye |
| Switches 1 | ||||
| Switch | 3PDT on/off/on | 3PDT ON/OFF/ON | legend: 3PDT on/off/on?; read from the layout by eye | |