Help me with my first pedal (High Pass Filter)

[mushjoon]

Hi guys, this is my first ever pedal. I tried to make a high pass filter pedal for bass that cuts frequency below 40 Hz.

I used a 0.033uf capacitor and a 120k resistor. I actually don't remember the exact values of them right now, but I know that I ordered the correct parts.

However, only LED comes on when I turn on the pedal. There is no sound coming from the speakers, regardless of being turned on or not. Is there something that I'm doing wrong here?

Also I tried to connect the ground wire to the wall of the box with a tape, but I don't think I've done a good job with that....

[Cozybuilder]

Here's a useful site for learning about and calculating appropriate values of components for high pass filters: (Your values give a knee at 40hz)

http://www.learningaboutelectronics.com/Articles/High-pass-filter-calculator.php#answer1

Regarding the ground wiring- the bodies of the input and output jacks (Sleeve) are connected to the enclosure, which are mechanically connected to signal ground. You should connect the battery ground to the switch center lug, as power is only used for the LED in this passive circuit.

It appears the battery positive is connected to the cap, not the 3 resistors making up the CLR.
Likewise, the CLR appears to be connected to the output jack, rather than the battery +.
The circuit output (blue wire) should be taken from the cap/resistor junction, not at the resistor/ground junction.

I would imagine this will short out once the lid is screwed on, you need to plan out the lead dress so that is not possible.

[mushjoon]

Here's a "clearer" picture of my pedal.

The bottom left of the 3DPT is marked as 1 and top left is 3.

[Cozybuilder]

1. Connect the battery neg to the center lug of the 3PDT switch, nowhere else
2. Connect the battery pos to the CLR (one end of your three 1K5 series resistors, nowhere else
3. Move the blue wire to the capacitor/120K junction
4. Connect the ground side of the 120K to a jack sleeve
5. Keep the connection between the jack sleeves
6. Other connections appear to be OK
7. Now wrap electrical tape around all bare connections before replacing the lid.

[GGBB]

It looks to me like when the pedal is turned on, the output is connected to the blue wire which is connected to ground - therefore the output is grounded == no sound.

Try this instead (what Cozy wrote):


The mechanical connection of the box and jack grounds will suffice, but you can if you want run a wire between the jack grounds for certainty.

[mushjoon]

Thanks everyone!

I was able to fix the pedal and now my bass sounds more clear.