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Joe Gagan is right - Bob Starr'sOctavia

10/13/2000 9:30 AM
Joe Gagan is right - Bob Starr'sOctavia
The Bob Starr Octavia is actually really fun!  
Made with 100% Radio Shack parts, - the only subs I made were using a .1uF input cap and a 10uF instead of 220uF coupling cap to the transformer.  
The only thing weird is that I had to have the input drive level all the way up for it to work well for me.  
Otherwise, the Shaka 3 through this thing is like a good Tycobrahe and reminds me of a Foxx Tone Machine.  
Very easy to make and it really does do the octave thing quite well for what it is. Just remember to match the diodes well.  
You need to download the massive archive unfortunately to get the schematic.
10/13/2000 2:13 PM
Eric H

"The only thing weird is that I had to have the input drive level all the way up for it to work well for me."
You can change the gain of the LM380 from 20x (the default) to 200x, by adding a cap (possibly between pin 2 and 4 --from memory). Check the data sheet.  
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10/13/2000 5:28 PM

Yes, I remember this.... I forgot to say, it was VERY easy to build - much more so than any other octavia device.  
It sounds very good!  
It's so easy, it could be a first project.
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