You're good to go. Just have a look at the schematic in the PDF file and you will see for yourself.

Btw, it's not pin two but pin three of the IC (U24) that connects with R131 and the negative side of C31.



Maybe read up on this to get the noise section correct, there has been a revision done:

viewtopic.php?f=16&t=155

And you can find the revision in the 808 service manual too! See page 8 on the right and page 15 bottom left.

http://www.ericarcher.net/wp-content/up ... vc-man.pdf

I recommend to install sockets on all IC's.

I feel like I'm allready to throw in the towel....

Its very difficult to match parts. I would have paid an extra couple hundred dollars just to have a "kit"with parts pre-sorted by build section. Its an incredibly time heavy project, just sorting the parts alone, let along trying to figure out what parts keep changing from the BOM etc...sorry, just frustrated.

I'm only at the noise section and can not get a good 130mv reading. The numbers just keep moving all over the place. I changed the one resistor to a 47k...didnt help. I've checked according to the schematics as to where continuity should be, to see if I screwed anything up - my soldering is looking horrible, and there is a tremendous amount of flux coming off the board it seems.

I'm not sure what to do next...I'm ready to bag it all up and throw it on ebay to get some of my money back...I feel like if I'm this stuck so close into it, that it's not going to be a fun project to continue, and I cant see my workbench being taken up with this for the next 2 months, because I only have a few hours here and there to work on it.

I dont want to move on to the next section unless I can figure out what the problem with the noise section is...

hi , to measure mv in ac mode you need good true rms multimeter. Leave noise section and go to next instrument, follow instructions and be careful during process, that's my advise. Probably you will need to update noise section as it is in 808 manual.

In my experience i've found that the "noise generator" is simple to assemble, but very important for the sound of the entire machine. If i well understand, the difficulty in having the right tension is caused by the tolerance of construction of the transistors used and maybe also because all the components are cheap. I could not get the 130 mV also adopting the mods in the service manual, but the sound quality of the noise obtained satisfy me and it looks like the original. I would not worry too much about this problem and go forward. You have no choice, you must continue!

I don't have a multimeter that is accurate enough for the noise section, so I just installed a trimmer instead of that resistor (can't remember the number, but it's the one with all the suggestions) and trimmed it to taste. You can do it by ear if you've got good recordings of an 808 to compare to.

80sboy wrote:I feel like I'm allready to throw in the towel
...
I dont want to move on to the next section unless I can figure out what the problem with the noise section is...

Hey, DONT DESPAIR!
I built the whole yocto without having the noise part measurements right. I just socketed the noise transistor and all ics.

I am fine tuning things now, that my build is over. It has not been a difficult or overlong build, and the sheer excitement of having an 808 drives me.
It is an amazing kit, Vincent is a very helpful guy and this forum cant be beat, so dont despair, and go on please.