Page 1 of 1


Posted: Mon Oct 30, 2017 10:27 am
by Rarecomponentadsr
There is a PCB track and component pattern on the web of the Moog 901b which looks authentic.

Has anyone made a 901b clone using this diagram ?

If you did.....does it work ?

Sorry I don't know how to post the image and I cannot find a link.

(Component values in red/green. Track links in blue)

I found that this had been posted on Electro-music forum a while ago,

Re: 901b

Posted: Mon Oct 30, 2017 10:33 pm
I've made one if we are talking about the same layout and it works.
901B layout.jpg
I have a few more 901a and 901b layouts in .pdf if you want them.

Re: 901b

Posted: Tue Oct 31, 2017 7:40 am
by Rarecomponentadsr
That's the one....thanks for putting this up.

And thanks for letting me know that it does work. I've made up circuits off the web only to find out they didn't work properly... very frustrating.

Regarding this actual circuit, the author I believe, suggested to use identical resistors and diodes around the unijunction transistor if making a bank of say three oscillators. This may help me in a tracking problem I've been getting on one of my own clones.