Roland AP-7 Jet Phaser - let's get it working! (Aion FX Octatron)

Well, I'll be the first to throw this up.

It's not "DONE" as the distortion side isn't working and I haven't had the chance to figure it out.
But since we're looking at the behavior of the phasing I thought I'd focus on that.

I initially biased according to the build doc, -1.35v but I wound up biasing by ear to get the best phasing. I found the exact opposite of the build doc in that small adjustments on the trimmer make a pretty big difference in the phasing. I wound up somewhere around -1.78v.

Having said that, I have some oscillation that modulates with the phaser even when not playing. I can't seem to dial it out with the trimmer.
It "could" be dirty power at my house.

As far as the phasing itself, it sounds good. Using the 4 stage it sounds somewhat like a Boss PH-1r. 6 Stages is pretty cool and may be my favorite setting. 8 stages gets into Mutron-ish land.

Regarding the "thunk", @aion can you be more specific about what the issue is? Or point to a clip on the issues?
I'm not hearing anything like a clunk, or a hiccup at the bottom sweep if I'm understanding correctly.

Couple of tips.....if you haven't built it yet.
For Q12, use the 9th JFET that Kevin sent to you. I tried a TO-92 2SK208 initially and wasn't getting any phasing. I popped the JFET that Kevin sent in and it fired right up.

Secondly, Q11, if you're using the Interactive BOM it calls for a 2N5088. The build doc says to use a 2N3904. Use the 2N3904.
It SHOULDN"T make any difference between these two options but in my build, for some reason it did.

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Alright so i got mine together and did some quick tests. I haven’t dug into it much yet but the jet side on mine doesn’t work either. I haven’t explored much like I said but the phaser side does work. I did have to bias at -1.72 to get a good phase effect. The -1.35 starting point had very very very little phasing sound at all. All the controls work as they should and I am not hearing anything odd like the thunk. Maybe the thunk is only there when the jet side is working as well? Anyway we are off and running at least. I am curious to see if anyone else is having luck with the jet side.
 

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