PedalPCB Electrovibe Mini

fig

Village Idiot
What a sweet pedal! A really fun build with no hiccups. I used Adafruit low-profile feather headers. Perfect fit! The LDRs are matched and BIAS is set to ear. It's a quiet pedal, which given the effect, it has to be. I had several ideas for graphics but none made the enclosure (meh). The vibe is strong and full, as is the phase mode. All controls are full sweep and mostly useable (subjective).
The 3PDT switch board ended up below the main board and pin headers made the connection nice and neat!

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Build one!
 
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Nice build! I aligned my LDR’s to point at my bulb. Is it recommended to point them more up like yours? Also, how did you match the LDR’s?
 
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All I have is a TC1 component tester and a simple DMM so I suppose I can't match LDRs. Is matching them necessary?
It's my understanding that no real matching is required. I used an LCR45 but a DMM works fine and it's horseshoe rules matching. Testing and measuring components is one thing I do to hopefully avoid a gig in the TS section. It's also my way of learning a bit more about how each component functions within a circuit (my original goal with building pedals...how am I doing so far?).

Here's the datasheet for Siliconex LDRs; Screen Shot 2022-05-01 at 8.42.13 AM.png

I confess that I did not allow the cells to adapt to 30-50ftc for 16 hours prior to taking measurements, although they were enjoying the glow of my maglight for awhile while I was on break :cool:

Vactrols (optocouplers) are another story....more on that as it becomes relevant.

Questions? Answers? I'll take either!
 
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It's my understanding that no real matching is required. I used an LCR45 but a DMM works fine and it's horseshoe rules matching. Testing and measuring components is one thing I do to hopefully avoid a gig in the TS section. It's also my way of learning a bit more about how each component functions within a circuit (my original goal with building pedals...how am I doing so far?).

Here's the datasheet for Siliconex LDRs;View attachment 25817

I confess that I did not allow the cells to adapt to 30-50ftc for 16 hours prior to taking measurements, although they were enjoying the glow of my maglight for awhile while I was on break :cool:

Vactrols (optocouplers) are another story....more on that as it becomes relevant.

Questions? Answers? I'll take either!
So you measure their resistance under a light and then in the dark and choose LDRs with similar Ohm readings?
 
So you measure their resistance under a light and then in the dark and choose LDRs with similar Ohm readings?
Yep, that's basically it. If they are within datasheet tolerances and close with all three measurements, I call them matched. As with anything, the larger the sampling the closer you can get the matches (for circuits that are picky).
 
Any experience with GL-55xx series ldrs?

View attachment 25829
I have little experience period, but 10 lux is about one footcandle so the 7532 is around 10KΩ @ 10 Lux correct? That would not align with the dark resistance of about 6.8MΩ would it? I'm not sure if that is factored into the circuit or not....
 
I think this same question came up on a thread I started about the Duophase and iirc the 55 series should work? I looked at the data sheets the other day and did some math. Check out that thread.
 
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I believe I have 8 or so of the Digikey 9203 units slated for my modified EV Mini.

I think my big boy used the SBE/Jameco units.

I may look for something cheaper and more plentiful for the Monk Vibe.

Great build Tim!
 
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I've got a couple of Univibe boards I need to work on... now I'm inspired to actually get cracking... :D
 
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