HELP mobius trip looper

[thieves]

im trying to build this
http://www.generalguitargadgets.com/pro ... rip-looper

i cant get it to record -or to play what records, not sure whats happening.
i ve checked my wiring,soldering,components lots of times. i even built it a 2nd time on a new pcb with new components, still the same result.
i intaled the jumpers and conected pin 28 with a 0.1uf, i also read this thread
http://www.diystompboxes.com/smfforum/i ... ic=32651.0
but it didnt help at all:(

the dry pot works fine when the fx is engaged, i get a bypass signal , everything seems normal exept i dont record.
i also hear some scraching sounds when i turn the pots.
i didnt used a safe mode

anyone can verify this schematic works??

please im desperate:S

[thieves]

here are the voltages i get  with the both switch (rec and play) off

isd1020ap :   
p4 -- 4,98v     p9-- 4,98v   p10--4,98v   p16--5v    p23--4,98v     p24--4,7v    p25--5v    p27--4,98v   p28--5v

hcf4001  :
p1--4,98v   p2--5v   p5--4,7v   p6--4,7v     p8--4,98v   p9--4,98v    p12--4,98v   p13--4,98v   p14--5v

tl072 (close to isd):
p1--5,01v  p2--5,01v  p3--4,95v   p4--0v   p5--5v   p6--5,01v  p7--5,01v   p8--9v

tl072(bottom left of pcb)
p1--5v  p2--5v  p3--5v  p4-0v   p5-- 5v   p6-- 5v  p7--5v  p8--8,98v

1n4005v:      kath--9,06v  an--0v
1n914 (close to isd) :      kath--4,7v   an--4,98v
1n914 (close to 4001):       kath--0v   an--4,7v

[thieves]

soz the links doesnt work
here is the right ones:
http://www.generalguitargadgets.com/projects/28-other-projects/147-mobius-trip-looper

and
http://www.diystompboxes.com/smfforum/index.php?action=printpage;topic=32651.0

[Hides-His-Eyes]

It's a bitch of a project, I'll leave it to somebody that's actually tried it before!

[Badman]

did you check the flux capacitor?

[the3secondrule]

Did you ever get this working?

I'm having the same issues. will do full de-bug / voltages shortly, just wond'ring if you had any tips...

[AVBear55]

I'm having the same exact problem!!! I came on today to look for help. At least I can take comfort in the fact that other people are having the same issue. It's not just me. So frustrating though. I've been working on this for the last couple of days. I etched a board for it and was very disappointed when it didn't work.

I did notice something however. the schematics contradict the PCB layout in two areas. Here is a link with the schematics and the PCB Layout. I assume we used the same since we are having the same problem. I noticed two things. one was that terminal 1,2,3,5,6,26 for the ISD are supposed to be seeing ground however when i checked on my meter i got a reading of 1.7v. In the layout you can see that all these point connect but there is no connection to ground. I grounded those leads but i still got nothing.


http://www.generalguitargadgets.com/pdf/ggg_mobius_trip_analog.pdf

http://www.generalguitargadgets.com/pdf/ggg_mobius_trip_pcb_lo.pdf

The other odd thing was that terminals 2 and 3 for IC U3 (TLO 72) are supposed to see a resistor that leads to a capacitor, leading to a terminal on the ISD chip. In the schematic term. 2 on U3 leads to term. 14 on the ISD, and 3 to 15. The PCB layout however has it reversed.  2-15 and 3-14. I'm going to try switching that around and see what happens and I'll be back.

[AVBear55]

Never mind, nothing happened.  I have no idea what the problem is. The chip could be shot. not sure