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Circuitbenders Forum => Circuitbending discussion => Topic started by: PolyPhuckin on January 15, 2009, 12:19:52 AM

Title: LTC1799 Precision Oscillator
Post by: PolyPhuckin on January 15, 2009, 12:19:52 AM

Has anybody had a go at making the Precision Oscillator posted up on the GetLofi.com (http://www.getlofi.com/?page_id=1302) site?

Just wanted to know what peoples experiences with it were before i ordered the chip.

Cheers

Title: Re: LTC1799 Precision Oscillator
Post by: Gordonjcp on January 22, 2009, 02:13:19 PM

It looks okay, but how accurate do you need your oscillator to be?  If the chip is cheap enough then fair enough, but I'd just use a little single-tranny oscillator for a few MHz and up, or a couple of NAND gates for up to about 1MHz.

Title: Re: LTC1799 Precision Oscillator
Post by: PolyPhuckin on January 23, 2009, 12:00:11 AM

To be honest its only so i can have an adjustable pitch on my SA-21.

I think they're £2 a pop and SMD.

Title: Re: LTC1799 Precision Oscillator
Post by: Gordonjcp on January 23, 2009, 02:09:59 PM

What frequency is the crystal or ceramic resonator in the SA-21?

Title: Re: LTC1799 Precision Oscillator
Post by: Bogus Noise on January 23, 2009, 02:37:32 PM

22Mhz I think. There's a good bit of info about changing the SAx crystals by Paul Oceanus on Casper Electronics, haven't tried it with a precision oscillator though, would be interesting to hear how you get on! I'd guess if it works it will probably crash if you change the pitch while it's switched on, but be ok to set the pitch before turning it on.

http://www.casperelectronics.com/finished-pieces/casio-sa-keyboards/

Title: Re: LTC1799 Precision Oscillator
Post by: PolyPhuckin on January 25, 2009, 09:37:37 PM

i've actually just finished that mod on my SA-5 but i used a 3PDT instead of a DPDT. It works really well.

This is where i first saw the idea, so i thought i might give it a go http://www.getlofi.com/?p=1383#comments

Title: Re: LTC1799 Precision Oscillator
Post by: the_zombiest on January 26, 2009, 11:16:36 AM

I think these are great. I've got one in my sk-1 and a couple of vtech toys. They do the trick and offer a really stable osc with a good range. The boards are already populated so you don't actually need to solder the chip onto the board, just the wires. You've gotta be careful how much power goes to the chip though cos anything over 5v is gonna burn it up.

Title: Re: LTC1799 Precision Oscillator
Post by: PolyPhuckin on January 26, 2009, 09:23:29 PM

cool, i think i'll go ahead and have a go building my own.

i'll tell you how it works out.

Title: Re: LTC1799 Precision Oscillator
Post by: Bogus Noise on January 28, 2009, 06:18:29 PM

Cheers for the link, I'll give it a try next time I open an SA! Good luck with yours :)

Title: Re: LTC1799 Precision Oscillator
Post by: PolyPhuckin on January 29, 2009, 12:39:34 AM

Thanks man.

Well, the chips arrived today, so, time to break out the etching tank (i have to buy one first though  ;D )

Title: Re: LTC1799 Precision Oscillator
Post by: Bogus Noise on January 29, 2009, 01:07:07 AM

hahaha... I know *exactly* what you mean!

I will get one... one day...

Title: Re: LTC1799 Precision Oscillator
Post by: strssmmnt on February 28, 2010, 01:59:15 AM

I really like the LTC1799... I've put one in an sk-1, and I will do another soon!