Audio Probe
This is very simple yet very useful tool
for debugging new pedals. You need one 1/4″ mono plug, one 100nF
capacitor, alligator clip and some wire. Connect alligator clip to jack
shield and 100nF cap to jack tip. When debugging some circuit connect
clip to circuit ground and use other end of cap (or wire connected to
other end of cap) to follow signal path through circuit. Plug the probe
into amp and plug guitar cord to pedal input (pedal output stays
unplugged). Make someone play guitar while you’re probing circuit and
once you find a spot where nothing is heard through amp you found a
possible problem.
If you have a cap small enough you can fit into plug
casing. It will look nicer and cap will be protected inside. It can be
seen on this photo how I did it. If you can’t find any slave around to
play guitar while you’re probing the circuit it’s not a bad idea to
connect guitar cable to sound card output and just play some music on
computer.
The other way to make this useful tool is using 1/4″
jack socket and regular guitar cable. Advantage over previous design is
that you need shorter probe leads and you can use as long guitar cable
as you need.
If you have a cap small enough you can fit into plug
casing. It will look nicer and cap will be protected inside. It can be
seen on this photo how I did it. If you can’t find any slave around to
play guitar while you’re probing the circuit it’s not a bad idea to
connect guitar cable to sound card output and just play some music on
computer.
The other way to make this useful tool is using 1/4″
jack socket and regular guitar cable. Advantage over previous design is
that you need shorter probe leads and you can use as long guitar cable
as you need.
This probe includes resistors / some noise protection
Original Source: http://diy-fever.com/misc/audio-probe/
No comments:
Post a Comment