News:

Forum may be experiencing issues.

Main Menu

[SOLVED][HELP] No effect (just clean) on EQD Tentacle

Started by neil463, April 15, 2017, 07:44:29 PM

Previous topic - Next topic

neil463

    I'm working off of this layout:
http://tagboardeffects.blogspot.com/2016/11/earthquaker-devices-tentacle.html

Schematic:
http://imgur.com/7trLVjz

Album of board:
http://imgur.com/a/6NGxf

Troubleshooting:
Measured Transistors and Resistors, used sound probe. 

Outcome of troubleshooting:

  • R3 is supposed to be 160k, but when it's on the board it's only measuring @ 125 (replaced with a new resistor that I measured at 160k off,  reading 125k once it was on the board).
  • 4 resistors had no audio on one leg - see the circled spots on the diagram http://imgur.com/IdOADyb
  • Q3 had no audio on the C leg
  • Ran razor between the traces to try to ensure no bridges were there
  • Verified transistor pinouts to make sure I had them in correctly (I did)
  • All pins on transistors had audio
  • Transistor Measurements





TransistorCBE
Q15.132.041.47
Q23.655.185.81
Q39.44.33.82


Not sure what to do next.  The resistors that don't have audio on one leg all measure out ok, so I'm not sure why they wouldn't at least have some passing through.  Admittedly I don't really know much at all about electronics so I hope what I'm telling you is helpful.

Thanks in advance![/list]

somnif

#1
The resistance of a R on the boar may look a bit funny because once its part of the circuit, your DMM is seeing the rest of that circuit. That charge is going to take the path of least resistance, so, you stick probes on either side of a 160K resistor, but there is a 125k path around it, that is what it will take.

I do see one error in your layout though. The anode side of D1 should be on the lane below the output line, on your board they are on the same line. Should just be the output wire, one side of the 100n cap, and the 47k resistor on that lane until the cut. You have a diode wired there too.

somnif


neil463

Sorry for the delay - that was exactly the issue.  The effect isn't as pronounced as in demo videos on Youtube, but I'm gonna chalk that up to production values.