Moodring 2015 No blend from GTR

[klonisgayjplay]

Hey guys, first post in awhile.

Let me preface with saying, i know. i should have a test rig. This is literally my next step as a builder. I have put it off. No longer will i do this. This is the second build ive had go awry and its super frustrating.

Anyways, im not getting a blend signal from the guitar just sort of "reverb noise, and feedback"

Things ive noticed.

When the effect is turned OFF, i get a bypass signal. The guitar comes through the amp perfectly.

When the effect is turned on I get a slight delayed  guitar signal. Very distant sounding.When i turn the trimmer down it increases the gain on the delayed signal but not the guitar.

When i engage the kill switch, i lose all sound.

Also im using the BTDR-2H Long. Not medium as reccomended.


On IC1 the TL072CP im getting 8.2v on the first leg.

More Voltages.

Ic1 TL072CP
8.1
2.1
4.4
0
4.4
4.9
1.4
8.2

Ic4 TL072CP

4.4
4.4
4.1
0
4.1
4.3
4.3
8.8

Ic3

4.9
2.4
0
0
2.7
2.4
0.7
0.7
2.4
2.4
2.4
2.4
2.4
2.4
2.4
2.4






Going through the parts now

[blearyeyes]

Try re-flowing the solder on the mix pot. You could also add some to the solder side .  You really need to make an audio probe. It could even be a capacitor and a wire going into any kind of amplifier  powered speaker something for an iPod  etc.  Print out the diagram of the layout and the schematic then start at the input and follow the money. You'll find a place where the dry signal stops. That will be your culprit.

[klonisgayjplay]

literally building that, as we speak lol.

[madbean]

1st things first: ground that output jack when testing it outside an enclosure.

[klonisgayjplay]

1st things first: ground that output jack when testing it outside an enclosure.

Yes, I actually test this IN the enclosure. I know that's not advised, and I promise I'm building a test rig! I'm currently figuring out how to include a test probe in the rig.

Back to the moodring, with the output jack grounded, I run into the same problem.

[klonisgayjplay]

Okay, i have my signal tester.

I can get signal after C1 and R2.

HOWEVER on IC1, Nothing on pin one. Loud ramping up crashing noise on pin 2 Nothing on 3, 4 , 5, 6, 7, 8.

Also im not entirely sure i have an understanding on how the switch works.

Anyways i can send more pictures of the PCB hooked up. I tried to reflow some joints on the IC, no effect.

[klonisgayjplay]

Just checked resistors and Caps. so far so good.

[klonisgayjplay]

The signal goes right before resistor 2. Then immediately stops right after.

[madbean]

You're not going to hear a signal at pin2 of that IC. But, you should hear it at pin1. Your voltage on pin7 is too low. So, either there is something wrong with the soldering, the socket or the IC. Since your bias voltages (4.5v) are correct otherwise, the IC might be the culprit.

What I do in these case is actually pull all the ICs and audio probe incrementally. With IC1 removed:
-If you have a continuity checker  on your multimeter, verify that R2 and the empty pin2 socket have continuity. Verify that pin2 does not have continuity with pin3 or ground.
-With the IC still removed, verify that audio gets to the empty pin2 socket (you should hear signal there without the IC in). If you have no audio, then you have lost the signal at R2.
-If you do have audio at pin2, re-insert the IC and check pin1 for audio. Same problem? It's the IC. Pull an IC from a working build and try that. If it's still not getting audio at pin1, then there is something else going on....maybe at the board level like a tiny short with the soldering.

[klonisgayjplay]

You're not going to hear a signal at pin2 of that IC. But, you should hear it at pin1. Your voltage on pin7 is too low. So, either there is something wrong with the soldering, the socket or the IC. Since your bias voltages (4.5v) are correct otherwise, the IC might be the culprit.

What I do in these case is actually pull all the ICs and audio probe incrementally. With IC1 removed:
-If you have a continuity checker  on your multimeter, verify that R2 and the empty pin2 socket have continuity. Verify that pin2 does not have continuity with pin3 or ground.
-With the IC still removed, verify that audio gets to the empty pin2 socket (you should hear signal there without the IC in). If you have no audio, then you have lost the signal at R2.
-If you do have audio at pin2, re-insert the IC and check pin1 for audio. Same problem? It's the IC. Pull an IC from a working build and try that. If it's still not getting audio at pin1, then there is something else going on....maybe at the board level like a tiny short with the soldering.

Brian THANK YOU!! I was missing continuity from R2 to pin 2.. on to the next one!