Maxon ad9 (re-house in wah(kinda)) mess

[masonlewisdiesel]

Happy belated new years.

My buddy asks if I could "take a look at" his Delay pedal. "My buddy threw it in a wah shell years back" he says. Right then, I should've thought about it a little more, and briefly dismissed the idea. But no, I went ahead and accepted it. I was handed what felt like a wah enclosure and without looking at it, set it on the shelf till I left. I get home and pull the cover off this is what I see. So I look into it and try to find some documentation. I am going to have to pretty much restart from Ground Zero. Remove all the wires with the insulation burns and figure out a proper way to mount these two pots securely,etc.
my neighbor also added i also tried to adjust the tiny little pots inside, but it got worse when i did. And I really don't remember where they were."
So a simple re-bias changed into a project. But, it is what it is...

My question for you fine folks:

Looking at the schematic, from the factory that unit came with a delay level of 10K, a repeat of 20K, and delay time of 10k(pots not trimmers).

1: Is there any reason that the delay level would want to have been changed to a 250K?
2: What about the 100K that is on the rack and pinion(treadle) that came from the factory as a 10k?

I should change back to OEM values right? I guess I need some reassurance

Thank you very much! I don't do this for a living. I'm a diesel technician. But I hate, and I mean absolutely hate following other technicians that have done these kind of jobs. There's a special place in hell for people that do this just like there is for people that use wire nuts on vehicles.

[masonlewisdiesel]

wow what a mess
Heres the PDF if anyone is interested

IBANEZ AD9 PDF

[PRR]

WELCOME Lewis Diesel!! ?
I wouldn't touch that poor pedal with a ten foot pole. Not an empty threat: the poles are in-stock at my HomeDepot.
https://www.homedepot.com/p/Unger-10-ft-Steel-Telescoping-Pole-989380/316416892

[ElectricDruid]

Welcome!

It looks like a lot of work for a pedal that might not be that great. Thanks so much for posting the full service manual PDF, that's really useful. You'd be surprised how many people turn up here asking for help with something, but haven't even bothered to make the effort to find the schematic.

Looking at the schematic, it's a typical MN3205 delay with companding. The main "innovation" here is that they've pushed the delay time out to 300ms with a sample rate of 6.82KHz. That's a best-case bandwidth of around 3KHz, and 2.3KHz is more realistic. No wonder they followed it up with a 30dB/oct filter to remove the clock noise. You'd need something steep.
What I'm really saying is that it's going to be a very dark delay, and only just over a quarter-second at best. Is that worth the effort?

If you reckon it is, I'd start from scratch. Many of the connecting wires aren't original and don't match the colours in the service manual anyway, so you could cut everything off, clear out and clean up the connection points, and then rewire the PCB into a new enclosure (a 1590B or something). At that point, you might have something solid enough to start any actual debugging that is required!!

HTH

[masonlewisdiesel]

Yeah, you know... I don't think its worth it at all, to be honest. I dont care for Delay too much. I found a Marshall JMP I fell in love with but didnt have anywhere close to the $ for a late 60s head. So he went and bought it for me and gave me 6 months to pay for it, I don't know. now that i've had it a few months paid off, I just would like to do him a couple "solids". and for that reason i'll (probably) proceed. Was going to clean all the wiring up, fix the pad solder pads, and go from there. My big concern at this point is the 100K hot pot(Delay time) that is on the rack and pinion(treadle) that came from the factory from Maxon with a 10k for (delay time)?
Or even better, is there any reading sources you would recommend so I could learn how changing variable resistors will alter the circut?

Does that make sense?

Thank you so much for the response