my first project

neo644 · Joined: Aug 18, 2005 Posts: 43 Location: Argentina

hi.
i'm going to build this VCO as my first proyect and hopefully it will be driven by a ribbon controller to make some sort of electro-theremin or tannerin.
though i have some trouble fully understanding its construction.
what type are the potenciometers to control the frecuency (coarse and fine) ? i mean log or linear, or what will be best?
where are they actually conected in the board? i have figured out where the "course" pot is connected, but the other one is connected to a 2M resister which has no name in the schematics and i cant seem to find it in the pcb. kinda lost here.

and thats it for now. i'm also confused respecting the outputs. can i plug in an output directly a pair of earphones and will the volume be okey? or do i have to build some sort of VCA to go with this?

thanks in advance, i have found this forums to be very usefull as well as the information on this site! Smile

elektro80 · Posted: Sun Aug 21, 2005 12:08 pm Post subject:

You did see this one:

elektro80 · Posted: Sun Aug 21, 2005 12:17 pm Post subject:

This VCO might be a bit better:
http://www.paia.com/9720.htm

Too bad Tony Allgood has discontiued his brilliant VCO.
However, a company in the US has bought the manufacturing rights to his Oakley Modular System.
http://www.ear-group.com/oakley_start.html
They already have a few modules in production. These will be made both for the MOTM and the Doepfer systems.
The wonderful Wavefolder is already in production
http://www.ear-group.com/oakley_wavefolder.html

Tony can still be found at http://www.oakleysound.com/

It makes a lot of sense to get a VCO, VCF and some enevelope generators. LFOs are cool too. I consider that a basic system.

dnny · Posted: Sun Aug 21, 2005 2:31 pm Post subject:

hi neo644
if you want temperature compensated VCO whit very good PCB layouts, panel wiring diagrams and all.
try this one -

VCO
you can also Purchase the pre drilled PCB for 20$

but if you don't mind about drifting - your link will do the trick

hope this helps

daniel

dnny · Posted: Sun Aug 21, 2005 2:52 pm Post subject: Re: my first project

neo644 · Joined: Aug 18, 2005 Posts: 43 Location: Argentina

that looks good elektro80, but i'm not looking for a kit Razz

and dnny that vco looks much better and fully explained! thanks alot, i'm going to build that one instead!

adios

neo644 · Joined: Aug 18, 2005 Posts: 43 Location: Argentina

hey
i'm back because i'm having some trouble obtaining all the parts since i live in argentina.
i couldn't find these parts:
LF442 (can't i use a TL082? what is the actual diference?)
LM13700
MPF102 (it says you can use a 2N5457, but i have some trouble also finding this one, are there any other options?)

is there any other model that could replace these?

well, thanks again

dnny · Posted: Fri Aug 26, 2005 9:29 am Post subject:

DrJustice · Posted: Fri Aug 26, 2005 1:19 pm Post subject:

Hi neo644!

Some good info right there from dnny.

I'll just add that http://www.digikey.com/ has all of LF442, LM13700 and MPF102 in stock. Is it an OK option for you to order from them?

DJ
--

neo644 · Joined: Aug 18, 2005 Posts: 43 Location: Argentina

wow dnny thanks alot!!
i'll look into it and find out what i can get over here at a reasonable price.

DrJustice, sorry but i cant order international, that would be just too expensive.

adios