Help with Hydra Delay

[dawson]

Hello, thanks for reading:

I've finished my Hydra build but when I activate it, there is no delay effect. The signal passes and the "Level" control works. The "Mix" control passes unaffected signal at full CCW and fades to complete silence at full CW.

I moved a couple potentiometers off-board to change the layout slightly but I can't imagine that's part of the issue..

I measured all resistor & capacitor values before installing.

I've triple-checked the resistor color-codes.

I've replaced both TL072's and the regulator with no change in behavior.

I've connected the right side of R5 to ground as suggested here: https://forum.pedalpcb.com/threads/hydra-delay-not-delaying.3041/#post-24502
but nothing remarkable happened- no sign of the stock FV-1 settings.

Has anyone experienced this type of thing before?
Any help would be much appreciated.

Here's a picture:

 

[p_wats]

As someone who has had many FV-1 issues, there are a few common questions/places to check:

• Did you solder the FV-1 yourself? If so, you may want to check for bridges/reflow to ensure stable connections with the pins
• Do you have an audio probe? If so, do you get signal going to in to the FV-1 (usually pin 1) and do you get audio coming out of Pin 28?
• Have you measured the pins to ensure there is 3.3v coming off your regulator and getting to pins 4 & 8 of the FV-1?

I also see no dust cover on the back of the pot in the photo, is it possible the others below the board don't have any dust cover either and are shorting out against the board itself? (that wouldn't necessarily explain your symptoms, but you never know).

 

[dawson]

As someone who has had many FV-1 issues, there are a few common questions/places to check:

• Did you solder the FV-1 yourself? If so, you may want to check for bridges/reflow to ensure stable connections with the pins
• Do you have an audio probe? If so, do you get signal going to in to the FV-1 (usually pin 1) and do you get audio coming out of Pin 28?
• Have you measured the pins to ensure there is 3.3v coming off your regulator and getting to pins 4 & 8 of the FV-1?

I also see no dust cover on the back of the pot in the photo, is it possible the others below the board don't have any dust cover either and are shorting out against the board itself? (that wouldn't necessarily explain your symptoms, but you never know).

Thanks for getting back to me- this is super useful.
I did indeed solder the FV-1 myself.
My pots are not shorting anything but I'll probe & measure those pins on the FV-1 after I re-flow the chip.

 

[cooder]

When you reflow the chip hit it with plenty of flux before retouching. That's always good in my experience with smd.

 

[Boba7]

You sure about those pots not shorting out?

Otherwise yeah, the soldering doesn't look quite right, especially the FV1, so you might wanna reflow the chip and some resistors/caps here and there.

Good luck!