[sdiy] ASM VCF Problem

[fmg]

Frédéric Piron wrote:
> 
> hi all,
> 
> Well i'm still in need of some help with the vcf problem, so if a kind
> soul has any ideas on how I can resolve it, they're more than welcome.
> 
> Thanks for your time,
> 
> Fred

Hi Fred,

Looking at the ASM schematics:

1. Check for a large asymmetry in the P.S.
2. Measure the DC level of OTAs outputs (readjust offset if needed)
3. Put a small cap (22...47pF) between pins 1 and 8 of CA3140 (they like
   HF oscillate)
4. Check the integrator caps.
5. Keep participating in this great list ;-)

(Fast check: start at the point 3, use the fingers as a small cap)

--
Fabio Gonzalez
Posadas, Argentina