Swoosh! It's an XC Phase!

PedalBuilder

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Build Rating
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A few months back my name came up in the Mystery PIF thread, and @tcpoint generously sent me this PCB and a matched set of MMBF5457 JFETs. I finally got around to building it over the weekend. It's a fun build and I highly recommend it!

This was the first build where I soldered SMD transistors myself. To my surprise, it was quite easy. If you're on the fence about trying a build that uses SMD transistors, you can do it! Here's how I did it. First, firmly tape the PCB to your work surface with a couple strips of painter's tape. This will give you a steady surface for the following steps. Next, apply a tiny dab of hot solder on one of the JFET pads. Once it's cooled, use a pair of tweezers to place JFET on top of pads. Make sure that it's aligned with all three pads, and reheat the pad that previously had solder applied to it. Now the JFET should be fixed in place. Check that it's still aligned with all three pads. If it's not, reheat the solder joint and use the tweezers to reposition the JFET so that it's aligned. Finally, solder the two remaining terminals, and you're good to go.

As many have suggested, I used a TL022 for IC3, and a 2N5087 for Q5, but otherwise it's a completely stock build.

The bias trimmer is extremely sensitive, so go very slowly when setting the bias. But once it's biased correctly, you'll know at once. Swoosh!

Other details? I used my own I/O board and relay bypass board. The enclosure is a Tayda 125B in orange sand, UV printed with a gloss finish.

IMG_2724.jpeg IMG_2725.jpeg
 
Wow, super clean, looks great!

The enclosure art is a great nod to the original without overdoing it.

Also, that's a pretty cool lookikng I/O board. Based on the silkscreen it looks like your own design? What all have you got going on there?
Thanks! The I/O board is my own design, with some inspiration from others. It provides reverse polarity and over-voltage protection and has an extra 9v pad to power a relay bypass board. The PCB fabrication house assembles all of the surface mount components, so all I need to do is add the jacks and two zener diodes, and it's ready to go. The cutout in the middle provides room for the panel-mounted DC jack. The two holes on the left of the DC jack's pads are for (optional) strain relief for DC jack's wires.

IO Board.png
 
Thanks! The I/O board is my own design, with some inspiration from others. It provides reverse polarity and over-voltage protection and has an extra 9v pad to power a relay bypass board. The PCB fabrication house assembles all of the surface mount components, so all I need to do is add the jacks and two zener diodes, and it's ready to go. The cutout in the middle provides room for the panel-mounted DC jack. The two holes on the left of the DC jack's pads are for (optional) strain relief for DC jack's wires.

View attachment 77448
Can you share the circuit for the power section? I’m curious. Also do you omit the polarity protection diode on the main board?
 
Can you share the circuit for the power section? I’m curious. Also do you omit the polarity protection diode on the main board?
Sure, here's the circuit:

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My own PCBs do not include a polarity protection diode, as the circuit above renders them redundant. I would have omitted the polarity protection diode on the XC Phase PCB, but I didn't decide to use the I/O board until I was almost finished with the build. I was all set to put in the jacks and box it up when I realized that I didn't have any other 1/4" jacks on hand other than the ones that I use with the I/O board.
 
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