question about Z Vex lo fi loop junky

[ξεναγος νεκροπολης]

hello there people!
i want to build a lo fi loop junky. the best schem that i have round isd1420 is madbean's loophole.
i've already drew and build the mobius trip looper from ggg (you can find the layout in this forum).

my problem is that i can't achieve the vibrato+depth controls...

i've read almost everything, and tried lots of things.

if anybody hs any idea on how i could do this, it would be great.



things i've done:

http://tech.thetonegod.com/payback/payback.html


this had some old tape style results but not good enough and without the depth control

https://wraadefects.wixsite.com/pedals/single-post/2019/02/03/ISD1420-LoFi-Looper-Sample-Rate-Reducer


i couldn't try this one cause i don't have the cd 4093
http://www.madbeanpedals.com/forum/index.php?topic=2172.0

thanks
Savvas