Vertex Boost

tcpoint

Member
I've already traced it. Then I moved and can't find my schematics. I might have to trace it again. The volume pedal interface is the highlight. The ferrite bead is kind of cheesy.
 

tcpoint

Member
What was it a copy of? Also on the input wire or like an inductor?
I think it was an original design. The bead is on the input. It is opamp based and the optional volume pedal resistance is in parallel with the feedback resistor. If I remember, one half of the opa2134 is used as a buffer (which is always on) and the other half is used for the boost. Wouldn't take much to roll your own. I need to look through some stuff, anyway. I will try and find the schematic. No luck. I started tracing it, again. I got the power section traced and the input. Still, need to finish the signal and the volume. It's a MAX1044 that gives you +/-9V. Will probably have time to finish it up this weekend. Anybody, have any ideas on how to measure a ferrite bead. I guess I could get a signal generator and send some high frequencies through it and see where the cutoff is. I could always make a guess of 600-1000R. Got it roughly worked out. Need to desolder a couple caps to measure them. Luckily, the resistors have the values on. It's mostly smd.
 
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tcpoint

Member
Nope. Might work as well or better. I have all the values measured and most of the trace done. Just not feeling too well, today. There's a charge pump in the vertex, the bypass is different, values are different. I made a boost about 5-6 years ago that is way overkill. Maybe, I'll revisit it and put a volume pedal on it. I still need to publish my mods to the Steel String.🤨
 

tcpoint

Member
About got the trace done. I was sick, last week. Just figuring out how to make all the switching look neat in a schematic. Then I'll verify the trace. There are some "interesting" design decisions.
 

dorrisant

New member
"Interesting"... Can't wait to see. I'm thinking of making a go of one of these. I'll try to stuff it into my Ernie Ball volume pedal.
 

PedalPCB

Administrator
Staff member
This is supposed to have 20db of boost. How does it look?
I looked at that schematic a while back. Somewhere later in that thread I believe the designer discouraged building that particular circuit.

Whenever tcpoint finishes up the schematic we'll jump right on that one. :D
 
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