Dr Phybes Rehab/Modification

[Chuck]

Best I can tell I originally finished the first version of this one in 2016 or 2017.  It’s been rehoused twice already and I had pulled the board to rehouse it again, then forgot about it.  Found several web discussions and videos about modifying Phase 90s and decided to take a different approach – where’s the fun in a pedal with just one pot and one switch?

Here’s the face:

And the guts:

The smaller knob is for the depth mod – there are a couple of versions floating around, I settled on pulling R30 (1M) and replacing it with a B1M pot with a 470K resistor in series.  Checking values with my multi meter with the pot all the way down gets me a baseline at about 485K and with the pot all the way up I’m just over 1.5M – ‘That’s great, Chuck – what’s it sound like?’ – at the bottom end there seems to be more distance between the top and bottom of the phase with less distance when the pot is cranked.  This seems to effect the rate some.  Some versions of the depth mod suggest just replacing the resistor with a B1M pot – I’m not certain in that case that all of the pot rotation would be usable.  The ‘s’ switch is the Script Mod described in the build document – I used a 33K for R16.  The  ‘hf’ switch is the 45/90 switch.  The green 3mm LED is attached to lug 3 of the rate pot as a rate indicator – It just turns on and off with no fancy fade in and out.  Barry supplied the Dr Phybes board, 3DPT board and bi-color LED,  purple pot condoms (they are there, trust me), hook up wire, and transistors; the tan resistors came from a stash I bought a Radio Shack many years ago – they were oddly very good; blue resistors, ICs, sockets, DC jack, stomp switch, and Lumberg jacks came from Small Bear. I stumbled across the orange 125B box on the Tayda site and decided it fit the bill for this one – the fit of the bottom of this one is amazingly tight.

Thanks for looking,

Chuck

[Chris]

Nicely done, I may try that depth mod for sure.  And I think we can agree we all like a tight bottom. :-p

[Anonymous]

You forgot the 45/90 wilkie mod. 🙂  Nice work as usual Chuck.

[Chuck]

Wilkie1, the switch is there (upper right corner) but I did forget to attribute that mod to you.

Chuck

[Anonymous]

Ah, shucks.  I must have read your description too fast.  I missed the 45/90 switch.

 

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