Yellow Magic sort of works. (Resolved)

Everything is in working order so far… except for the delay. I’ve spent some time using my multimeter to test voltage outputs etc. and I have hit kind of a wall. Has anyone else built a Yellow Magic and ran into some silly issues? Anything overlooked? Scratching my head here.

Some batches of the delay chips require a resistor change to work reliably, it’s documented on the web page for this filter board.

i have the same issue (everything works just no echo at all) but i haven’t looked after it yet. maybe i find time tomorrow, would be cool to have it working

I really hope all it takes is replaceing a resistor. I love the way this filter sounds.

Indeed there are some batches of the delay chips that require some adjustments to components.

It´s all in the Filter´s assembly page

I’ve had this issue with chips from Small Bear, these require 39k for R58 and have the type of Stamping in the first photo.

The chips I got from Mammoth Electronics worked with the Spec 22k for R58. They have the type of Stamping in the second photo. Not sure if they are all prone to this issue or if the ones with this Stamp won’t latch up.

Thanks! That is super helpful. I got mine from Small Bear and it looks like that stamp. Maybe this kind of thing should go on the Wiki?

this worked for me, i have echo now, except for i cannot change the speed, i.e. changing the time parameter has no effect at all. level, feedback and eq work like they should.
i suspect the infamous badsolderjoint™ or do you guys have an idea?
btw mine is like in the first pic too, albeit probably from banzai


Cool! Glad it´s working. I love mine, think that the delay function adds a whole dimension of possibilities

it’s a bit weird. i’ve reworked the connectors pads again as well as a lot of others. it’s stuck on a time value until i touch the headers pads with a finger. then it seems to sample a new one and gets stuck with this, also producing weird noises/modulations in the process, which could be just echoing some bleeps or sth.
also the pot itself works and changes things in other menus so i think it has to be somewhere on the way in the echo part. gonna do further checks maybe tonight

Don´t forget to set the Shruthi to Delay on the configuration page or else it wont work.

And also save that configuration :slight_smile:

I kept forgetting that …

i’ve had it set to delay all the time but it never worked. since the resistor change it does work but there is a bug in changing the delay time. the other parameters work.
there must be a bad connexion somewhere, because a touch causes it to do once what it should do always. of course it’s not me, it’s because it was from the beta run :wink:

Is the voltage on the DAC output steady?

I had also problem that delay was always on and delay time didn’t work and other parameters worked,. my problem was MCP4822 DAC chip so maybe check that out…

thanks a lot, it is one of my suspects (touching this also has an effect)
i’ll check the DAC output …tomorrow (luckily i have a few spares)
i swear i’ll think twice before soldering ics in again

ripped off some pads, things get worse and worse now every time i try. i think i’ve misused this board now to a degree that it would be time to start a new one. i didn’t have a yellow control board anyway.
anyways thanks guys

You could always scratch the solder mask off… :x Not nice, but works. Unless you cut through the traces while doing so :stuck_out_tongue:

I would suggest you leave it be for a while, and come back at it in a few days/weeks/months when your patience has recovered. It always works for me!

Maybe after you assemble another YM?