Ibanez AD-80 AD80 picture request

[newperson]

Hello,
Does anyone have a picture of the output wiring for the old Ibanez AD80 delay pedal?  I have one the looks to have a ground wire cut on the output jack but I cannot tell where it would go or if someone at some point cut one wire and just added a new one in place of the cut wire.  It has 3 black wires coming from the ground side with a 4th black wire cut. 

The pedal is passing clean signal only.  The blend takes out all the clean, but the other two knobs don't seem to be doing anything to the signal.  Just like the delayed path has a break in it. 

Thanks for any leads,
Paul.

[Dan N]

Here's some guts:

http://www.sonicurbs.com/ibanezAD-80/index.htm

Sounds like your issues are beyond a ground wire.

[newperson]

thanks, i have seen those and a couple more but nothing shows the wires going to the output jack.  i was hoping someone here owned one and would open it up and take a shot of the output jack.

guessing too that it is more than the wire, but i am trying what i see first.  audio probing to find out where the signal goes away tomorrow hopefully.

thank you for the reply,
paul.

[oldschoolanalog]

I have an AD80. What I don't have right now is a camera . Anyway, there are 3 black wires connected to the output jack. One goes to the switch (under the foam). One goes directly to the ground lug on the input jack. And one goes to a circle on the PCB marked "5 BLK". This is right by the DC jack.

Sounds like your issues are beyond a ground wire.

Big time +1.
BTW, I got this for $10 DOA. Some testing showed the NE570 was fried. After replacement & calibration it works great.
Nice delay definitely worth fixing. When I get my camera back I'll take some photos if still necessary.
Audio probe it & maybe post some V's.
All the Best!

[newperson]

thanks for the list!  that is the same for me.  i just have a 4th small stub of a black wire attached with a clearly resoldered look that i wanted to make sure that it was okay.  i will post the power values for you to take a look at soon. 

[newperson]

hello oldschoolanalog,

here is what i found,

MN3005
1    12.02
2    5.72  high pitch
3    6.14  pitch
4    6.16  delay pitch
5    0
6    5.72   high pitch
7    5.55   normal input pitch
8    .76


mn3101

1   11.43
2    5.72  high pitch
3    0
4    5.72   high pitch
5    11.35
6    .35
7    9.07   delay high pitch
8    .76



tl022
1    5.99   pitch
2    5.99    pitch
3    3.95   pitch
4    0
5    5.9
6    5.98
7    5.98
8    12.02


ne570

1     .90         weak signal
2     1.77       signal
3     1.77        signal
4     0
5     1.79
6     1.75
7     5.9
8     1.78
9     1.78
10    11.21
11    11.21
12    2.98        signal
13    12.02
14     1.77    delay signal
15     1.77    delay signal
16     .29      weak signal



bal trimmer has delay signal
level trimmer has delay signal
bias trimmer no signal
repeat trimmer no signal
clock trimmer no signal


and i am using a oscillator for the signal.  i am also calling it pitch on some of these readings because sometimes the oscillator was reading a higher sounding pitch with the audio probe.   

got any guesses for me? 
thank you,
paul.

[oldschoolanalog]

Sorry for the delay (bad pun ).
Here's the V's of my functional AD80. Conditions: 18V reg. power supply. All knobs 12:00. No input signal. I'll take more readings w/a test signal later.
NE570/  1: 1.13,  2: 1.9,  3: 1.9,  4: 0,  5: 1.9,  6: 1.9,  7: 5.7,  8: 1.9,  9: 1.9, 10: 7.8,  11: 7.8,  12: 1.9,  13: 12.1,  14: 1.9,  15: 1.9,  16: starts at .8V and slowly goes down  . I'll recheck this pin later w/an input signal applied. I'm very curious about this...
TL022/  1: 6.1,  2: 6.1,  3: 5.7,  4: 0,  5: 6.1,  6: 6.1,  7: 6.1,  8: 12.1
MN3101/  1: 11.5,  2: 5.8,  3: 0,  4: 5.8,  5: 11.4,  6: .5,  7: 9.4,  8: .78
MN3005/  1: 12.1,  2: 5.8,  3: 5.8,  4: 5.8,  5: 0,  6: 5.8,  7: 5.7,  8: .78

I'll check the test signals you posted later. Right now, our V readings don't look too far off. Try centering all your trimpots and see what happens. More to come...
Dave     

[oldschoolanalog]

Quick update on NE570 pin 16. Careful inspection of the board revealed a bunch of crud accumulated through the years. After a good bit of isopropyl & patience the board was cleaned. Now there is a steady reading of .85V at pin 16.
Lesson relearned. Clean is good.

[newperson]

Thank you for the readings.  I only see four that are off any and 3 of those for are on the ne570 chip.  I am going to look around to see if I can find one I can take out of another delay and put that one in the AD80 just to check that chip out.  Hopefully it will be that and not one of the transistors. 

Did you ever find out if my signal test matched yours?

Thank you again,
paul.

[newperson]

I did not have any luck finding the ne570n chip.  I was thinking this was the chip in the pt80 but I have a 571 in that one.  I just placed an order for one. 

[oldschoolanalog]

OK. Looking at the schematic:
http://www.freeinfosociety.com/electronics/schematics/audio/ibanezad80.pdf
You have signal at the input (pin7) & output (pins 3 & 4) of the BBD; level trimpot; and pins 14 & 15 of the 570 (input of the expander). There should be signal at pins 10 & 11 of the 570 (output of the expander). Is there any?
Just saw your post while typing.
NE/SA571 will work OK. 

[newperson]

no signal and those are the pins that have the higher 'wrong' voltages verses your correct readings.  i will swap in the 571 and try that.  just so i know, what is the difference between the 571 and the 570 chips?

[newperson]

let there be delay.  that was the chip.  so your voltage readings are right on.  i have to mess with the trimmers a bit because i centered them, but it is working just fine. thank you for taking your unit apart, posting the voltage readings and looking to see where there should be output.  it is nice to know there are such helpful people out there that are willing to go that far to help out a stranger.

one more question for you, is your power supply positive tip 18V or neg tip?

Thanks a million,
paul.

[oldschoolanalog]

...what is the difference between the 571 and the 570 chips?

Check this out (Thanks to StephenGiles)
http://www.ka-electronics.com/images/pdf/NE570_Applications.pdf
Page 1. The section about "Basic Operation". There's your answer .

...is your power supply positive tip 18V or neg tip?

It is a 1/8" mono jack. Positive tip 18V. IIRC, the schematic shows this.
Glad to hear you got things working Paul!
All the Best,
Dave