[sdiy] Help needed! - EFM VCO4d

[James Dunn]

Hi all,

I tried the pull-up resistor, which seems to work ok for the pulse 
output.
I also checked the signal at other points of the circuit and there 
might be something funny going on.. here's a picture of Pin 5 of the 
CA3046 - it's more noticeable at a this high frequency (still an 
audible frequency - just!) but the effect is apparent on all outputs.

http://www.4thharmonic.com/images/VCO4d/Pin5_CA3046_VCO4d.gif

cheers

James

On 22 May 2006, at 17:14, yves usson wrote:

> Hi James
>
> in such a case use a 820 ohm resistor for R25 (or even 680 ohm see 
> what fit!).
> For the pulse, add a 2.2K pull-up resistor between pin1 of the LM393 
> and the +15V rail.
>
> Cheers
>
> Yves
>
>
> James Dunn a écrit :
>> Hi Yves,
>> I am working with +-15V. I'll check out the resistors in the sine 
>> converter - thanks for the tip!
>> cheers
>> James
> -- 
> Yves Usson
>
>
>
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