What would cause static 3 components in?

[Luke51411]

I'm working on dead astronauts abductor delay and I am getting static as the signal enters the first opamp. http://www.diystompboxes.com/smfforum/index.php?topic=110419.0
I posted some details on that thread. I'll port them here when I get a chance. It is still there with pt2399s removed though they do amplify it. I'm getting the static at pin 1 of IC5. I've checked everything I can think of.

[Luke51411]

I socketed IC5 and tried others to no avail. The static is starting at pin 1 of IC5 it's present when on and bypassed and with pt2399s removed. It's much louder in long delay mode but I think the delay line is just cascading the static. The volume doesn't affect the static level. I socketed the jfet, removed it, tried another, no help. Removed C1 I think (100uf filter cap) and replaced it no change, I might try replacing other electros but I don't think that's it since the static is still present with no pt2399. Where does static come from? I do have a lot of offboard wiring, maybe it's coming from that? I'm running out of things to check, the dry signal path is short and is basically just both sides of IC5. I'll probably dig the probe out again and see whets happening again.

[midwayfair]

Is the static GONE when you remove the JFET? How about when you remove IC5?

If you remove the JFET, is there static on either side of D2?

[Luke51411]

Is the static GONE when you remove the JFET? How about when you remove IC5?

If you remove the JFET, is there static on either side of D2?

Removing the jfet did not remove the static. I haven't checked D2 yet but I will when I get a chance, thanks.

[midwayfair]

Is the static GONE when you remove the JFET? How about when you remove IC5?

If you remove the JFET, is there static on either side of D2?

Removing the jfet did not remove the static. I haven't checked D2 yet but I will when I get a chance, thanks.

Replace the op amp and reflow your solder joints.

[Luke51411]

Is the static GONE when you remove the JFET? How about when you remove IC5?

If you remove the JFET, is there static on either side of D2?

Removing the jfet did not remove the static. I haven't checked D2 yet but I will when I get a chance, thanks.

Replace the op amp and reflow your solder joints.

I've done that, I'll try a few more just to be sure but I've had the same issue with 3 opamps, checked continuity around at all the components related to IC5. Made sure nothing was bridging to one of the vias. I'll probably go through and reflow one more time to make sure. Isn't static usually a sign of DC getting through somewhere?

[midwayfair]

Isn't static usually a sign of DC getting through somewhere?

The presence of DC doesn't make the static sound you're thinking of (if it did, every single pedal would sound like static, because every pin of an active component has DC on it) -- that's caused when the DC changes. It's the same thing that causes a pedal to pop, except the pops are very small and happens very quickly.

[Luke51411]

Isn't static usually a sign of DC getting through somewhere?

The presence of DC doesn't make the static sound you're thinking of (if it did, every single pedal would sound like static, because every pin of an active component has DC on it) -- that's caused when the DC changes. It's the same thing that causes a pedal to pop, except the pops are very small and happens very quickly.

Ah ok thanks for the explanation.

[Luke51411]

.015v at pin 4 of ic5 the ground pad at the bottom of the board the same. The ground at the top of the board reads 0.00 I'm going to hardwire the ground at the bottom to my star ground and see if that does anything.

I think it helped a little but most of the noise is still there.

[Luke51411]

Ok I heard back from Rob, he checked voltages his original build of the abductor and got the following
IC5: in/out..
1:4.61v
2:4.61v
3:3.77v
4:0.00
5:4.58v
6:4.61v
7:4.59v
8:9.15v

I got something like this
IC5: in/out..

1:4.50v
2:4.50v
3:4.40v
4:0.00
5:4.50v
6:4.50v
7:4.50v
8:9.15v

Would .7v difference on pin 3 mean anything useful? He also mentioned that a few of the pot lugs aren't supposed to be connected so I'll try snipping those and see if they were acting as an antenna or something. At least I still have things to try...