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Test Box

Started by Josemitejam, March 04, 2021, 10:57:20 PM

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Josemitejam

Hi all,

I was looking to build this test box, I just wanted to be really sure of where all the cables are going to. I'm going off this picture on reddit:

https://www.reddit.com/r/diypedals/comments/8z17c6/how_to_build_a_simple_pedal_test_box/

if the lugs are set up as:

147
258
369

then it looks like:

3 and 6 are joined
1 and 9 are joined
1 is also going to tip of the input jack???
2 is an alligator clip that will attach to ____________?
4 is going to _______________?
5 is going to the sleeve of the input jack
7 is an alligator clip going to ________________?
8 is going to the tip of the output jack???

From the Input/output jacks it looks like:

the input jack sleeve is going to the dc jack's terminal 1 (an alligator clip is coming off of terminal 1 there too)

What is the red and blues wires in the bottom left of the picture going to?
How are the red wires that attach to the dc jack connected?
What does each color alligator clip connect to?

...I'm struggling with off board wiring right now, so I wanted to build one of these to make sure my board is in fact solid. Ironically, this is purely off board wiring, making the gods laugh right in my face...

Any help is appreciated!


Joe

GGBB

3 and 6 are joined yes
1 and 9 are joined yes
1 is also going to tip of the input jack??? yes
2 is an alligator clip that will attach to circuit input
4 is going to LED cathode
5 is going to the sleeve of the input jack yes - this is ground
7 is an alligator clip going to circuit output
8 is going to the tip of the output jack??? yes

From the Input/output jacks it looks like:

the input jack sleeve is going to the dc jack's terminal 1 (an alligator clip is coming off of terminal 1 there too) ground for circuit and power

What is the red and blues wires in the bottom left of the picture going to? red is power to the LED anode via a current limiting resistor, blue is switch #8 to output jack tip

How are the red wires that attach to the dc jack connected? one goes to LED, one goes to alligator clip for circuit power

What does each color alligator clip connect to?
green (white wire) to circuit output
yellow (blue wire) to circuit input
red to circuit power
black to circuit ground
  • SUPPORTER

Josemitejam

Perfect! Thank you for the quick and thorough reply! I'll be throwing this thing together tonight!


Joe

Josemitejam

So I got it all hooked up and the led lights up and the bypass works, but the circuit doesn't seem to work. Before I start diving into that I just wanted to double check and see if anyone is able to spot anything wrong With the off board wiring. I wasn't sure about my led wiring....There's a resistor in the circuit for the led and there's one under the yellow tape of the test box too....or could my two red wires from the dc socket be flip flopped?











GGBB

Does the circuit work outside of the box - that is, connected directly to power, ground, and jacks?

Does the box work without the circuit? Connect the circuit input and output to each other, and connect your meter to the power and ground wires to check for supply voltage - this will tell you if the wires are flipped.
  • SUPPORTER

Josemitejam

Hmm...I'm not sure I'm following those directions. When I hook it up to the test box I get  my clean bypass Just fine, and when I turn it on the LED lights up but no sound.

So when you ask if it works outside the box, am I still connecting it to the test box's power, ground and jack alligator clips? If so, how about the LED lead? The LED hookup is one of the confusing spots to me , although I'm assuming I hooked it up right if it was turning on.

When I check the box without the circuit, I can just connect the two alligator clips together for the input and output? And when I connect my multimeter what setting should I have it on and what reading am I looking for? As of now I haven't gotten a reading, although I may still be doing something wrong. If I don't get a reading , where might the problem lie? With the dc jack terminals being flip flopped?

In the meantime I'll be probing through the schematic to see if it is the circuit.

Thanks so much for your time again! Off board wiring has been a mystery for a long time now so I'm glad I'm finally confronting it!

GGBB

#6
You've established that bypass works and the LED works. You need to find out whether the test box is not passing either power or signal to the circuit, or not receiving signal from the circuit. First test for signal by bypassing the circuit - connect to clips that would go to circuit input and output to each other (looks like the two yellow clips). Now you should have direct guitar sound in both bypass and engaged mode.

To check power, set your meter measure DC voltage and connect the positive probe to the red clip and the negative lead on the black ground. It should read your supply voltage which I assume is about 9V.

If that's all good then it points at the circuit not working. Connect the leads of your circuit board directly to power, ground, input and output without using the box. Make sure you have ground connected to the signal in and outs as well. If the circuit is working the it was your connections to the box that were faulty - did you have input and output reversed?

One thing I cannot make out from the picture is how you have wired the power connections to the power jack and what type of jack it is. Some jacks - the kind most used in DIY pedals I think - have two positive connections. One is to supply power to the circuit and LED, and the other is to receive power from a battery. The battery connection is disconnected when you insert a plug from the power supply. Without any power plug inserted, the battery is connected to the other power connection and therefore sends power to the circuit. So you should have both the led power wire and the circuit power wire connected to the same terminal on the power jack.

This offboard 3PDT pedal wiring diagram might help:


  • SUPPORTER

Josemitejam

The culprit was the dc jack! I put my led and the circuit power wires on the same lead and wallah. Thanks a ton for your help and thorough explanations. There's nothing like finally getting a pedal up and running while simultaneously realizing another aspect of how this all works.

Unfortunately the Buzzaround still isn't working, but that seems to be the ic chip. My newly built Jordan bosstone proved the matter instead.

Thanks for your time and knowledge!


Joe

kaycee

Well done on persevering and getting it working.

The only other thing I'll add, is that being familiar with HB cartoons, 'JosemiteJam' made me chuckle to myself all day yesterday, well played :icon_biggrin:

Josemitejam

Hahaha good to hear that!