[sdiy] very simple vco

[Motohiko Takeda]

Hi jim, luca and list! 

> musically useful VCO...they only thing that might make it complicated is
> locating the Q81 type (+3300ppM) tempco resistor.

Now a days, TC is not hard to get item. I think.

So many years ago, it made from platinum, it's so expensive and hard to 
get. But now a days, here comes good and cheap material to make TC. 
It's thin metal film or something, I heard.

It may be used in electrical home appliance all around us as it's 
becoming so cheap.
I check the web and phone book just a little, and make 3 phone call 
then I can get it.
Please try in your place.
My "let's share the TC" project still go on. Try TC !

I think that, Small Dual TR is more hard to get now.  

ASM1 is simple I think. Rene's 4069VCO is also simple.

I had experimented this schematic 
http://www.aleph.co.jp/~takeda/radio/farmVCOIIe.html
it's pcb pattern.
http://www.aleph.co.jp/~takeda/radio/pdf/vco2.pdf

and this is almost same as asm1 VCO that I had experimented.
http://www.aleph.co.jp/~takeda/radio/img/farmVCOIII-scheme.gif
http://www.aleph.co.jp/~takeda/radio/pdf/vco3.pdf
I had used Japanese TR and FET for these VCO. Check it out for
their pin structure.
These are intended to use in musical use.

Cheers,
Motohiko Takeda
Tokyo Japan.