[sdiy] Anyone sucessfully built an EFM Vco4d?

[jeff brown]

Make sure that the "Sync In" is normalled to ground. My 4E wouldn't 
oscillate without it.

There was also an older erroneous 4D schematic that showed the "Sync Out" 
normalled to ground instead. Probably not good :)


----- Original Message ----- 
From: "Tom Arnold" <xyzzy at sysabend.org>
To: "Julian" <julian at 22host24.com>
Cc: "Synth DIY" <synth-diy at dropmix.xs4all.nl>
Sent: Tuesday, January 25, 2005 1:19 PM
Subject: Re: [sdiy] Anyone sucessfully built an EFM Vco4d?


> On Tue, Jan 25, 2005 at 11:15:27AM -0000, Julian wrote:
>> You do anythng special to it to get it to work?
>>
>> Just trying to work out if its my mistake or not.
>
> I'm not at home right now within reach of my VCO4D's, but are a couple of
> the TL074's getting very hot?  If so, check out the pinout of the FETs.
> Use the tri out as your test point and not square out as the square is
> missing a pullup resistor.
>
> -- 
> -----------------------------------------------------------------
> - Tom Arnold       -  Free Synth DIY webspace http://www.sdiy.org
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