Simple Fix for a 1976 Morley Pro Flanger

Last year, I repaired a 1976 Morley Pro Flanger (PFL) pedal, doubling its value in the process. 

It ended up being a simple fix, so I thought I'd share my brief repair notes.

Morley Flanger Repair Notes, 031713:

• Pot codes: 1377621 (May 1976)
• Pedal passes a signal in bypass
• Passes a signal when engage, but no flange effect  
• Checked switches – all worked fine.
• All solder connections seemed very solid.
• No obviously burnt out components.
• Because everything else looked fine, I started adjusting the trimpots, one at a time (I marked the original positions first of course).
• The 25k trimpot next to the 100k trimpot seemed to do the trick. When I adjusted it, flange became apparent in the signal.

Pedal worked fine in foot and auto modes after that.

For those that are not familiar with Morley, this pedal works by way of a black fabric at the far end that covers and uncovers a photoresistor as the pedal is moved forward and backward.

Biyang PH-10 Phase Adjustment

I recently purchased a Biyang PH-10 Phase Pro on eBay. I noticed that in eBay's stock photo of this pedal, SPEED is spelled SEEPED (seriously), so I wasn't sure what to expect. This one's not too bad.

The PH-10, like MXR's M-101 Phase 90 (the natural comparison in this price range), did not sound that great out of the box. I took it apart to see if there was an easily accessible trimpot inside, and there was indeed.

The stock sound was over-pronounced for me. I made careful note of the stock position of the trimpot screw and turned it little by little until it sounded good to me. You may end up with different results if you try this, but I ended up about 270 degrees counter-clockwise from the original position (see pic below). The pedal now sounds much creamier. If I don't sell it first, I will a/b it with an Custom Shop Phase 90 and a 74 Script Phase 90. One thing at a time, though.

The yellow dot indicates the stock (top) and adjusted (bottom) position of that end of the slot.