Monthly Archives: January 2014

ARP Odyssey VCO Prototype

Sounds good so far. Need another prototype as i goofed up a bit but quite happy it worked first time!

Edit 1 :

Final version will have Thru-hole transistors for the expo pair as I can’t get any good tracking with smd trannies. I’m tracking 3 octaves with MMBT3904/MMBT3906, 4 octaves with BC850/BC860. Quite ridiculous.

With a pair of 2N3904/2N3906, i’m getting 8 octaves of tracking (go figure…)

I’ll also change the Pulse Width trimpot to 1 turn as having a 25 turn there is making adjusting more difficult .

Still need to test how it behaves under +/-12V and to check temperature stability.

 

photo-2

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