[sdiy] MS 20 FILTER

[synth DIY]

hi! i have this MS 20 filter project to do and i've been have some problems:

in this schematic i don't really understand the meaning of the symbol in the
output of U1a and U1b.

"Vr" voltage is the ground voltage?

between pin 7 and 8 ( and 10 and 9 ) it's a buffer circuit. should i use any
specific kind of buffer?

Lm 136000 datasheet is not available, but i found a
http://www.datasheetcatalog.com/datasheets_pdf/L/M/1/3/LM13600.shtml.
<http://www.datasheetcatalog.com/datasheets_pdf/L/M/1/3/LM13600.shtml>
is it the same?


thanks
Diogo
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20051218/934b62fb/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: sk.gif
Type: image/gif
Size: 7042 bytes
Desc: not available
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20051218/934b62fb/attachment.gif>