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Title: Help with this Schematic
Post by: John Lyons on April 07, 2004, 11:12:22 AM

Hey there.

I can't figure out what +Vb means on this schematic.
+9 would be the battery positive tab but +vb stumps me. Maybe + volts bias? If it's bias where does this bias originate? I'm trying to build this as a 2 band Parametric eq pedal but there are a couple "missing" pieces in the puzzle.

Also how does the resistor and cap assortment (mid left of schem) tie in to the rest of the schematic?

Thanks in advance

John

Title: Help with this Schematic
Post by: smoguzbenjamin on April 07, 2004, 11:19:17 AM

Vbias is usually 1/2 of V+ or in this case 4.5v.

Post the link to the schematic and I can help you better ;)

Title: Help with this Schematic
Post by: Mike Burgundy on April 07, 2004, 11:35:05 AM

Look in the DIY FAQ (link above) and read the "Power Supply - What is V.R., V.B, VREF, 1/2V+ etc" bit. This will also give you an inkling where them resistors+cap arrangement tie in.
There should be a point marked Vb between the two resistors (resistive devider - cuts the voltage in half) and a couple of points in the schematic with the same label.
Rule in schematics: if points are labelled the same (A, B, Vb, +, ground, etc) they're tied together in real life.
hih

Title: Help with this Schematic
Post by: puretube on April 07, 2004, 04:28:02 PM

http://www.diystompboxes.com/sboxforum/viewtopic.php?t=21

plz scroll dwn to last post...

DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: John Lyons on April 07, 2004, 11:12:22 AM