Correction to the LAL 86 Oscillo Fuzz layout Hi! I’ve recently built the 86 Oscillo Fuzz and found that the original layout and schematic available online have a small but important wiring error. The correct version has the 470Ω resistor connected to +9V together with the 47k, and its other side joins a 10k resistor going to the collector of Q2 — this node is also where the 100nF output cap and Osc switch connect. I’ve redrawn and tested the corrected schematic — it now works perfectly, producing the expected fuzz and siren-like oscillation. Hope this helps anyone trying to get this great pedal working properly!– how can I upload the sechematics here? Thanks Sérgio
The 470r & 47k do connect to 9v through the protection diode, but the error is that the other side of the 47k goes to the base instead of the collector of Q1?
B/10 which is labeled Level 2, should be Level 1 instead?
ReplyDeleteWhere's the CV input from the original?
ReplyDeleteRead the Freestompboxes thread in the schematic link?
ReplyDeleteHi Anders, hope you're doing fine! Keep up the amazing work. I wanted to build this but it seems that the schematic shows lvl2/output is grounded :
ReplyDeleteYea, Level 1 should be grounded & Level 2 goes to Output as usual?
ReplyDeleteWhat other NPN general purpose transistors work well as replacement for the PN100?
ReplyDelete2n2222, 2n3904, 2n4401, etc. anything in the lower medium gain range?
ReplyDeleteCorrection to the LAL 86 Oscillo Fuzz layout
ReplyDeleteHi! I’ve recently built the 86 Oscillo Fuzz and found that the original layout and schematic available online have a small but important wiring error. The correct version has the 470Ω resistor connected to +9V together with the 47k, and its other side joins a 10k resistor going to the collector of Q2 — this node is also where the 100nF output cap and Osc switch connect. I’ve redrawn and tested the corrected schematic — it now works perfectly, producing the expected fuzz and siren-like oscillation. Hope this helps anyone trying to get this great pedal working properly!– how can I upload the sechematics here? Thanks Sérgio
The 470r & 47k do connect to 9v through the protection diode, but the error is that the other side of the 47k goes to the base instead of the collector of Q1?
ReplyDeleteNo, the 47K goes to collector of Q1 and base of Q2.
DeleteThe other side of the 47k should only connect to Q1 collector & not Q2 base
ReplyDelete