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 2720 VCO tuning 
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Joined: Wed Jan 01, 2014 1:36 pm
Posts: 61
Location: Toronto
Post 2720 VCO tuning
I have 1 2720-2 and 2 -2a vcos. none of them will tune to the same note per volt or tune to a proper scale. any suggestions?


Thu Feb 13, 2014 8:18 pm
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Joined: Sun Nov 09, 2008 2:49 pm
Posts: 725
Post Re: 2720 VCO tuning
Just posted the procedures for setting up these two models of PAiA VCOs over at the 2720/4700 area linked below. Cross your fingers and hope for the best with the 2720-2: It wasn't long before the 2720-2 VCO design was updated to be the 2720-2A with a more accurate zero-intercept implementation.

viewforum.php?f=31

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Scott Lee
scott@paia.com


Fri Feb 14, 2014 5:06 pm
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Joined: Wed Jan 01, 2014 1:36 pm
Posts: 61
Location: Toronto
Post Re: 2720 VCO tuning
I was finally able to get my oscillators in tune (correct scale)
- 2720-2 I changed cap C1 and then added a 343n cap in parallel
- 2720-2A I added the zero mod, changed C1, and changed R5 to 14k
- 2720-2A I added the zero mod, changed C1, removed R5, and replaced
R8 with a 5K multi turn trim pot.

I'll have to see how well this holds up under use

Bill


Wed Feb 19, 2014 11:52 am
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Joined: Fri Feb 21, 2014 5:20 pm
Posts: 1
Post Re: 2720 VCO tuning
Hi! I'm new here. How the heck do I do a new post? I have a vintage PAIA keyboard that I'm trying to find info about.

Thanks
Marcus


Fri Feb 21, 2014 7:30 pm
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Joined: Wed Jan 01, 2014 1:36 pm
Posts: 61
Location: Toronto
Post Re: 2720 VCO tuning
click on New Topic


Fri Feb 21, 2014 10:57 pm
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