Circulator "Saturn Phaser"

Nice build! Why did you remove R100?

It was causing the green LED on the bicolor LED not to illuminate. But now the effect is not working it seems. The knobs control the phaser but only if they are moved manually. I am going to have to troubleshoot it. It worked fine before I messed with R100 but that is probably a coincidence.
 
Not a coincidence. If you replaced R100 with a jumper, then the green LED is loading down the LFO and causing it to not work. Mr. PedalPCB said in another thread that the LFO does not have the capability to drive some 2-color LEDs.
 
It was causing the green LED on the bicolor LED not to illuminate. But now the effect is not working it seems. The knobs control the phaser but only if they are moved manually. I am going to have to troubleshoot it. It worked fine before I messed with R100 but that is probably a coincidence.
What you described is what the middle function of the 3 position toggle does. It "parks" the frequency so you can manually sweep the phase, dialing in the cocked wah sound. By chance, was it in that position when you tested it?
 
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For what it's worth, I used this LED with the 1k CLRs and have had no problems. It seems that different LEDs may have different forward voltages that may be interfering with the LFO's operation.
 
This LED is common anode I believe, I got some from GuitarPCB a while back. I will replace R100 and just deal with one color.
 
Hey I’m curious to know if you’ve compared the phaser in this one to the duo phase you built.

I’d like to build either the circulator or phase ii soon but haven’t heard from anyone who’s owned or built both.

here’s my impressions just from research.
Pros for eqd:
-can really dial in the sound you want with the extra knobs.
-vibe mode is cool, though not quite the same as a photon vibe type pedal
-no trimmers or ldrs to mess with
Pros for mutron
-vintage circuit = cool
-maybe the base tone is better/cooler than the eqd even if you don’t have all the controls of the eqd

let me know what you think after if you get a chance to compare them. Thanks
 
For what it's worth, I used this LED with the 1k CLRs and have had no problems. It seems that different LEDs may have different forward voltages that may be interfering with the LFO's operation.
If the LEDs try to draw more current than the LFO can supply, then the LFO output sags and the LFO stops. The amount of current that the output can deliver depends on the RATE pot setting. Maximum LED current draw depends on R33, R100 and the two LED's Vf. If the resistors are made large enough, then the LFO won't freeze. Except when the RATE switch is in the middle position and it's supposed to freeze.

EQD only drives one LED, the little red one next to the RATE knob, with the LFO.
 
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