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Tagboard Effects

MXR Phase 90 - 4 / 8 Stage

Based on the MXR Phase 90 - 4 / 8 Stage

Category
Phaser
Controls
Speed
Build
Vero· 21×23· 28 cuts, 20 links
Layout
Unverified · no build reported at Tagboard Effects yet
Tags
MXR, Phaser

From the post

I was going to just add this to the bottom of the Phase 90 post, but on reflection thought it better to start a new one to keep discussion about this build in one place.

A few people have requested a layout for the Phase 100 and I thought this could be a happy medium until I start on the circuits that are currently a low priority due to my preference for PCBs when it comes to larger circuits to keep the box dimensions down.

I was happy with the size of the Phase 90 layout and so I thought it would make sense to make this modular rather than using a large single board as it will then allow you to add more daughterboards if you want to, maybe two to make a 12 stage phaser if you like, or three for 16 stages.

The standard Phase 90 layout was used as an example in this layout, but you could do exactly the same thing with the modded version with the depth pot if you prefer. This inserts the new stages in between stages 2 and 3 of the main Phase 90 board which means that all other components of the Phase 90 can remain exactly the same, making it easy to add this to an existing build if you want to. All you need to do is add a cut and make the switch connections shown at the top of the Phase 90 layout and the daughterboard, daisy chain the supply and ground and link the sources and gates as shown. Voila, you have a Phase 90 with 4 or 8 stages selected by the Stage Switch.

I haven't done this from a verified schematic and so it's all just theory at this stage, so it's definitely one for the experimenters out there. And of course the people who don't mind matching at least 8 JFETs :o)

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 Tagboard Effects. No KiCad fragment has been drawn for this circuit yet.

Parts list 28 rows

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Check before you build · 1 value the reader of this layout was not sure of
  • 15u electrolytic at the bottom of the main board next to D1: printed clearly, unusual value
RefValueNormalizedTypeNotes
Resistors 8
×1710K10kread from the layout by eye
×922K22kread from the layout by eye
×6150K150kread from the layout by eye
×21M1Mread from the layout by eye
×2470K470kread from the layout by eye
×13M93.9Mread from the layout by eye
×156K56kread from the layout by eye
×14K74.7kread from the layout by eye
Capacitors 5
×1047n47nread from the layout by eye
×210n10nread from the layout by eye
×147u47uelectrolytic; read from the layout by eye
×115u15uelectrolytic; read from the layout by eye
×110u10uelectrolytic; read from the layout by eye
Diodes 1
D15V1 zener5V1read from the layout by eye
Transistors 9
Q12N59522N5952JFET; read from the layout by eye
Q22N59522N5952JFET; read from the layout by eye
Q32N59522N5952JFET; read from the layout by eye
Q42N59522N5952JFET; read from the layout by eye
Q52N41252N4125read from the layout by eye
Q62N59522N5952JFET; read from the layout by eye
Q72N59522N5952JFET; read from the layout by eye
Q82N59522N5952JFET; read from the layout by eye
Q92N59522N5952JFET; read from the layout by eye
ICs 1
×5TL072TL072ICs are TL072; 3 on the main board, 2 on the stage board; read from the layout by eye
Potentiometers 1
SpeedC500KC500kPotentiometerReverse Log; read from the layout by eye
Trimmers 1
×1250K250kread from the layout by eye
Switches 2
ScriptSPSTSPSTread from the layout by eye
StageDPDT on/onDPDT ON/ONread from the layout by eye