Doepfer

Hi Dieter,

> MM5837 data sheet (digital noise source)
> Digital Noise Generator of the Formant Synthesizer (Book Elektor 
Verlag,
> ISBN 3-921608-19-8, 1981, pages 24-25)
> Digital Noise Generator published in the magazine Elektor about 
1978/1979

Thanks for those pointers - I found that book online, and through it 
discovered the circuit is used in quite a few others places: the ETI 
3800, 4600 & 5600, and it is also mentioned in Barry Klein's book 
too, though unfortunately none of these give any decent analytical 
treatment of it. However I finally managed to work through most of 
the theory myself, to the point where I could deduce the period as 
2^18-4, so agreeing with the brute-force calculation of the whole 
sequence. If anyone is that interested, I gave the bare-bones of it 
on the Synth DIY list, available in the archives here:

http://search.retrosynth.com/synth-diy/search/lookit.cgi?-v0805.169

Tim