MXR™ Phase 100™

This is the original MXR™ Phase 100™ Phase Shifter Replica known as P100. Thanks to Stephen Giles for sending some documents to make this project possible. Due to obsolete optical parts, we no longer stock the PCB or kit for this project, but the information is still available below. Any Trademarks mentioned here belong to their owners and not General Guitar Gadgets

Project files

Everything you need to build it

PDF · Start hereGeneral Build Instructions↓PDF · 6 pagesPhase 100™ Build Instructions↓PDF · 6 pagesPhase 100™ Bill of Materials↓PDF · 1 pagePhase 100™ Schematic↓PDF · 1 pagePhase 100™ Parts Layout and Wiring Diagram↓PDF · 1 pagePhase 100Parts Layout and Wiring Diagram using two toggle switches instead of the rotary switch.↓

Phase 100™ Ready-For-Transfer Printed Circuit Board Layout

Schematic

Parts layout

Parts Layout / Wiring Diagram

Phase 100Parts Layout and Wiring Diagram using two toggle switches instead of the rotary switch.Open full size Download PDF

What you will need

Bill of Materials

Resistors

Resistor ID	Value	3-band Marking	4-band Marking
R1	15k	brown-green-orange	brown-green-black-red
R1 (alternate)	29.4		red-white-yellow-gold
R2	10k	brown-black-orange	brown-black-black-red
R3	10k	brown-black-orange	brown-black-black-red
R4	10k	brown-black-orange	brown-black-black-red
R5	10k	brown-black-orange	brown-black-black-red
R6	10k	brown-black-orange	brown-black-black-red
R7	10k	brown-black-orange	brown-black-black-red
R8	10k	brown-black-orange	brown-black-black-red
R9	10k	brown-black-orange	brown-black-black-red
R10	10k	brown-black-orange	brown-black-black-red
R11	10k	brown-black-orange	brown-black-black-red
R12	470k	yellow-violet-yellow	yellow-violet-black-orange
R13	20k	red-black-orange	red-black-black-red
R14	20k	red-black-orange	red-black-black-red
R15	20k	red-black-orange	red-black-black-red
R16	100k	brown-black-yellow	brown-black-black-orange
R17	100k	brown-black-yellow	brown-black-black-orange
R18	6k2 (6.2k)	blue-red-red	blue-red-black-brown
R19	6k2 (6.2k)	blue-red-red	blue-red-black-brown
R20	10k	brown-black-orange	brown-black-black-red
R21	10k	brown-black-orange	brown-black-black-red
R22	10k	brown-black-orange	brown-black-black-red
R23	10k	brown-black-orange	brown-black-black-red
R24	10k	brown-black-orange	brown-black-black-red
R25	10k	brown-black-orange	brown-black-black-red
R26	10k	brown-black-orange	brown-black-black-red
R27	10k	brown-black-orange	brown-black-black-red
R28	10k	brown-black-orange	brown-black-black-red
R29	10k	brown-black-orange	brown-black-black-red
R30	10k	brown-black-orange	brown-black-black-red
R31	10k	brown-black-orange	brown-black-black-red
R32	150k	brown-green-yellow	brown-green-black-orange
R33	20k	red-black-orange	red-black-black-red
R34	20k	red-black-orange	red-black-black-red
R35	100k	brown-black-yellow	brown-black-black-orange
R36	100k	brown-black-yellow	brown-black-black-orange
R37	100k	brown-black-yellow	brown-black-black-orange
R38	100k	brown-black-yellow	brown-black-black-orange
R39	47k	yellow-violet-orange	yellow-violet-black-red
R40	47k	yellow-violet-orange	yellow-violet-black-red
R41	150k	brown-green-yellow	brown-green-black-orange
R42	3K9 (3.9K)	orange-white-red	orange-white-black-brown
R43	22k	red-red-orange	red-red-black-red
R44	150k	brown-green-yellow	brown-green-black-orange
R45	6k2 (6.2k)	blue-red-red	blue-red-black-brown
R46	47k	yellow-violet-orange	yellow-violet-black-red
R47	20k trimmer
R48	39k	orange-white-orange	orange-white-black-red
R49	120k	brown-red-yellow	brown-red-black-orange
R50	6k2 (6.2k)	blue-red-red	blue-red-black-brown
R51	100k	brown-black-yellow	brown-black-black-orange
R52	150k	brown-green-yellow	brown-green-black-orange
R53	150k	brown-green-yellow	brown-green-black-orange
R54	20 ohm	red-black-black	red-black-black-gold
R55	150k	brown-green-yellow	brown-green-black-orange
R56	4k7 (4.7k)	yellow-violet-red	yellow-violet-black-brown
R57	Speed Control Potentiometer

Capacitors

Capacitor ID	Value	Type	Possible Marking
C1	0.01µF	Film	103
C2	300pF	Ceramic or Film	301 (or 300pF)
C3	0.01µF	Film	103
C4	0.01µF	Film	103
C5	0.01µF	Film	103
C6	0.01µF	Film	103
C7	1µF	Tantalum ( or Aluminum Electrolytic)	1µF
C8	0.01µF	Film	103
C9	0.01µF	Film	103
C10	0.01µF	Film	103
C11	0.01µF	Film	103
C12	0.01µF	Film	103
C13	0.01µF	Film	103
C14	15µF	Tantalum (or Aluminum Electrolytic)	15µF
C15	15µF	Tantalum (or Aluminum Electrolytic)	15µF
C16	0.01µF	Film	103
C17	15µF	Tantalum (or Aluminum Electrolytic)	15µF

Potentiometers

Part ID	Value	Type
R47 - Center Frequency (trim)	20k	Trimmer
R57 - Speed Control	500k	Reverse Log Taper (or 100k linear)

Other

Part ID	Part Name
IC1, IC2, IC3, IC4, IC5, IC6	TL022
VR1, VR2, VR3	VTL5C2/2 or VTL5C3/2
6 - jumper wires or 0 ohm resistors	Jumper (6 times)
D1	1N914
D2	LED (status indicator optional)
Q1	2N5088 (or other NPN BJT) Transistor
Q2	2N5088 (or other NPN BJT) Transistor
Q3	2N5088 (or other NPN BJT) Transistor
Q4	2N5088 (or other NPN BJT) Transistor
J1	Stereo quarter-inch jack
J2	Mono quarter-inch jack
J3	DC Jack
B1	9 volt battery (not included in the Kit)
Sw1	Heavy Duty 3PDT foot switch
Sw2	2-pole 4-way rotary switch ( or 2 SPST toggle switches) 9v battery snap, Printed Circuit Board, 24 gauge stranded wire, Enclosure, Knobs

Download the BOM (PDF)

How to build it

Instructions

This is a replica of the MXRTM Phase 100TM referred to as P100 in these documents. This is a replica of the original, vintage, real MXRTM unit, not the DunlopTM reissue. This is very versatile and unique sounding 10 stage phase shifter. An excellent set of sounds controlled by a 4-way switch that ranges from mild phase sounds to an intense phase that almost borders on chorus pedal sounds. The unique sound of this unit can be heard, used by Keith Richards of the Rolling Stones on their song "Shattered" on the "Some Girls" CD Among many other recorded examples of that time period. Use the project documents provided, starting with the General Build Instructions. It will fit nicely in a 1590BB or 1590NS enclosure, with a little planning. We use a Lorlin (manufacturer name) PCB-mount 2-pole rotary switch that can be set to any number of positions up to 8. We chose the PCB-mount version to keep the profile low so the board would fit over it. We clipped off all the unused terminals and bent down the terminals that we soldered to. This kept the profile of the switch low enough to fit the board over it. Then we used double sided tape to hold the board in place and insulate the terminals of the rotary switch. The holes for the jacks need to be drilled as close to the top of the enclosure as possible and enclosed jacks should be used. All the “jumpers” are included in the top layer of the PCB, so you don't need to add any jumpers to the components of the PCB. When you install the capacitors, especially C7 if the radial capacitor is tall, make sure that you lay it down flat before you solder the leads. There's not much “head room” between the PCB and the bottom plate, so everything needs to be low as possible.

You can also see this in the photo below. The kit includes IC sockets. When we built this one, we decided not to socket anything. We're not against using sockets, but for whatever reason, we soldered the ICs straight to the PCB. In some cases the P100 will oscillate on the "regenerated" settings. This can be fixed by replacing the 15k R1 resistor with a higher value resistor. The kits include a 15k resistor and also a 29.4k resistor to use in R1 if you encounter oscillation. There are a couple of mistakes on the PCBs that need to be considered. The screen print on the top of the PCB shows the diode in the wrong direction. Follow the layout and look at the photo below for the correct installation of the diode. Also a last minute addition to the PCB to add the LED current limiting resistor (R59) is not correct, so you'll still need to add the 1k resistor inline with the LED wiring and don't add R59 to the PCB.

The kit comes with a Lorlin adjustable rotary switch. The collar around the pole should be set in position 4 when the switch has been turned to the most counter clockwise position. The back of the switch has numbers and the poles are labeled with letters. The chart below describes the connections to the switch using the wire colors shown in the wiring diagrams.

Pole A (Pad “AP”)

Pole C (Pad BP)

8 (Pad “B2”)

3 (Pad “A3”)

4 (Pad “A3”)

10 (Pad “B2”)

Comments and questions are welcome and can be sent to [email protected]

Download the PDF