Hi Dieter,

Thanks for your response. I have now had a chance to pull an A-156 out of the rack. From what I can see it looks like that TLC274 is the input buffer. If that chip has a 10mV offset I was wondering if it might be worth swapping out the TLC264 for something like an LT1014 (150uV offset).

Do you think it’s worth trying or am I doomed to get the soldering iron out

Best wishes
John

> On 4 Jun 2018, at 09:47, yahoo@... 1 < Doepfer_a100@yahoogroups.com > wrote:
>
> Hello,
>
> unfortunately there is no offset trimming available at the A-156 module. P1,
> P2 and P3 are just attenuators (with buffers) but do not offer an offset
> feature. One would have to add an offset externally or modify the A-156 (by
> adding trimming potentiometers and resistors for offset adjustment). I can
> tell you details if required.
>
> Best wishes
> Dieter Doepfer
>
> > -----Ursprungliche Nachricht-----
> > Von: Doepfer_a100@yahoogroups.com [mailto: Doepfer_a100@yahoogroups.com ]
> > Gesendet: Freitag, 1. Juni 2018 19:33
> > An: yahoo@... 1
> > Betreff: 1 A-156 input threshold tracking
> >
> >
> > Hi Dieter,
> >
> > I am using 4 x A-156 together. The input threshold tracking is
> > usable but a bit tricky with one of the modules being slightly
> > different. I have read the A-156 adjustment guide and have the
> > correct tools to hand. I understand how P1, P2 and P3 adjust the
> > input scale but would like to understand if recalibrating them
> > might help with a little input offset. Any thoughts appreciated.
> >
> > Many thanks for your time and attention.
> >
> > Kind Regards,
> >
> > John Hollis
>
>
>