Vintage Phase 90 problem

[AntKnee]

I'm building a vintage phase 90, the six IC version, and I'm not getting full phase out of it. I can get a beautiful phase effect if I manually manipulate the trimpot back and forth, but it won't phase on its own. I have tried all manner of adjustments to the trimmer, but all it does is output the tone created by the trimmer position, with no "wave" to it. I was hoping someone could point me in the right direction based on those symptoms, if possible.

I used a set of 2n5952 trannies that I matched myself, so I know they should be good.

I apologize for not having a schematic. I built this from an etched pcb made from a layout I got from FSB, which did not include a schematic and I don't know what schematic it is based upon. I didn't post voltages because my build doc and layout do not even have IC numbers to relate the voltages to. You can find the doc I used to build the pedal here: https://dl.dropboxusercontent.com/u/13215910/Script%20Phaze%2090.pdf

[jimilee]

The pin outs on the trannies are opposite the 5452 trannies. Did you check that? Also check for bridges against the mask that you used to etch the board.


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[AntKnee]

The pin outs on the trannies are opposite the 5452 trannies. Did you check that? Also check for bridges against the mask that you used to etch the board.


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Ah, a fellow phaser lover.

Yeah, bridges was my first check. I don't see any that shouldn't be there.
My layout is made for 5952, so I don't think orientation (opposite the 5457) is the problem.

[AntKnee]

So, yeah, it was a solder bridge near the trimmer. It only took my 3 rounds of checking to find it!

[Zigcat]

This one?

[jimilee]

Nicely done sir. I do love a good phaser.


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[AntKnee]

Nicely done sir. I do love a good phaser.


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It sounds good, not as bright as my Nom Nom and a tiny bit more lush than my block logo phase 90.
It does have a heckuva pop in the footswitch, though. It may need a pull down. It doesn't have electro caps, so I can rule out a leak, I think.

[somnif]

Are those 50nF'ers Class Y caps? I'm not used to seeing the Blue splayed-leg look on standard components.

[AntKnee]

I don't know what class it is, but here is the link. I didn't expect them to be blue or have these legs. The pictured item is different, but it does say that the actual item may differ from the picture. I just wanted it to be larger than the tiny ones I keep ending up with from everywhere else. I wanted it to resemble the original phase 90 components.

http://www.newark.com/multicomp/mccc250v503my5u/ceramic-capacitor-0-05uf-250v/dp/97M4051?ost=97M4051&searchView=table&iscrfnonsku=false&ddkey=http%3Aen-US%2FElement14_US%2Fsearch

[AntKnee]

Hate to renew this, but I've still got a bad pop with the footswitch. I am measuring 2.4v at the input! I'd suspect a leaky cap, but there are no electrolytics in this circuit. What else should I look for?