DBA Reverberation Machine - No Sound

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A2K
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DBA Reverberation Machine - No Sound

A2K
Hello!

I've just finished building the DBA Reverberation Machine and unfortunately, I'm not getting any sound from it when testing.

http://tagboardeffects.blogspot.com/2015/10/death-by-audio-reverberation-machine.html?m=0&_sm_au_=iVV48SMF7sZTrnsN

I've attached a few pictures that will hopefully help with debugging. I know I should post the voltages from the IC, but I'm afraid that I don't really know how to do that! If someone would be kind enough to explain how I would be happy to post those as well.

A few notes that might be helpful:

1) I have built it to include the decay pot and momentray switch as per Marcello M's instructions in the comments section. That's why you'll see 2 loose wires coming off of the BTDR daughterboard I have ( I don't have the pot for the decay control as of yet).

2) It seems weird to me that nothing is connected to lug 3 of the Gain pot. Am I missing something there?

3) I put a trimmer in the R1 position

Pictures:

https://imgur.com/a/23GkF1a

Thanks A TON in advance to anyone who can help me out here. I'm still a newbie but have learnt so much from this site. This is my 6th or 7th build and the first one I haven't been able to get working on my own, so I will send you endless good vibes if you can help me :)
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Re: DBA Reverberation Machine - No Sound

squirrels
I’m not too sure but try connecting the two wires.
A2K
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Re: DBA Reverberation Machine - No Sound

A2K
squirrels wrote
I’m not too sure but try connecting the two wires.
Thanks, but that didn't work. Which makes sense because those wires are only used to create a feedback loop between the bricks input and second output.

(I'm assuming you meant connect the two loose wires off the brick's daughterboard)
A2K
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Re: DBA Reverberation Machine - No Sound

A2K
Hmmm so i just looked at the BTDR datasheet and it says that pins 2 and 4 are internally connected, which would make my link between those pins unnecessary...any chance this would be creating a problem?
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Re: DBA Reverberation Machine - No Sound

Sentenza
In reply to this post by A2K
Hi!
At first glance, the diode 1n4001 has the positive leg connected one row above.
Nothing is connected to the 3rd lug of the Gain pot.

Here are the working voltages of my build:

V: 8.73V

IC (TLC27M4AIN)

1) 4.01 V
2) 4.01 V
3) 3.82 V
4) 8.02 V
5) 3.82 V
6) 4.01 V
7) 4.01 V
8) 2.1 mV
9) fluctuates
10) 12 mV
11) 12mV
12) 3.82 V
13) 4.02 V
14) 4.01 V


L7805

O: 4.76 V
G: 0 V
I: 8.04 V