A/DA Flanger no sound with pedal engaged

[mort]

I'm very unskilled at pedal repair so asking for a little help.

The bypass mode passes guitar signal but with the switch engaged there's no sound except for just a very small noise while sweeping the enhance control. Otherwise it's silent.

I've given it a visual inspection and read 20v on the secondary of the transformer. Not even sure where to go from there.

Thoughts?

[dmeek]

Since you can hear some sound at the output I would guess the problem is at the input. The enhance pot feeds the output back into the delay chip.
Maybe a bad 3403 op-amp or missing power supply voltage. It's split 4 ways, at least on this schematic. Yours might be a different version.
ADA-Flanger-schematic-10-186p-rev-D.pdf

[g1]

Apparently there is also a re-issue version. I don't think it would have the SAD1024 like in the schematic posted above.

[mort]

It has 10-205P molded into the inside of the enclosure. Doesn't have a sad1024.

225615 appears to be a serial number on both the back panel and the circuit board.

Just noticed this resistor on the trace side of the board. Possibly done at the factory? Appears to match the existing work. The one on the underside is positioned where the one on the top looks like it was supposed to be. Perhaps a board layout mistake that was fixed in this manner?

[vintagekiki]

http://adadepot.com/index.php?topic=148.0
Schematics and Mods
ADA Effects
https://elektrotanya.com/showresult?what=ADA

[g1]

Maybe one of the 10-189 or the 10-185 schematic, see attached

[mort]

Maybe one of the 10-189 or the 10-185 schematic, see attached

Didn't see a match but there's good info in there. Thank you. Looks like mine might fall around 1980 according to the serial number.

http://adadepot.com/index.php?topic=148.0
Schematics and Mods
ADA Effects
https://elektrotanya.com/showresult?what=ADA

That ADA board isn't allowing new registration, fwiw. Has current posts though.

[vintagekiki]

#7
That ADA board isn't allowing new registration...

http://adadepot.com/index.php?action=register
Please note "Depot New Registrations Temporarily Suspended" Please see discussions for how to register.
1)

2)
https://aronnelson.com/diywiki/index.php/ADA_Flanger

https://docplayer.net/37550920-Ada-flanger-clone-build-documentation-mn3007-version-pcb-rev5-january-2010-updated-feb-2012.html

http://moosapotamus.net/images/FlangerClone_SCH_rev5_MN3007_jan2010.gif


https://www.eserviceinfo.com/downloadsm/52170/ADA_flanger.html

ADA-Flanger-schematic-10-186p-rev-D.pdf

[mort]

Here's the layout, fwiw. Has the MN3010.

https://flic.kr/p/2mbZsPh

[vintagekiki]

Here's the layout, fwiw. Has the MN3010.

Schematics for Ada flanger with MN3010 see g1 post #6

ada_flanger_schematics.zip
ADA-Flanger-10-189-MN3010BBD-starting-with-pn-227331