From yahoo Sent Tue, Jun 12th 2018, 10:20
From yahoo Sent Tue, Jun 12th 2018, 10:20
Yes, two of the opamps of the TLC274 are the input buffers. You may try it out but from my point of view it would be more reasonable to add an offset circuit (trimming potentiometer + resistor) than to try out to find another opamp with a different offset. Best wishes Dieter Doepfer > -----Ursprüngliche Nachricht----- > Von: xxxxxxx_xxxx@xxxxxxxxxxx.xxx [mailto:xxxxxxx_xxxx@xxxxxxxxxxx.xxx] > Gesendet: Dienstag, 12. Juni 2018 10:45 > An: xxxxxxx_xxxx@xxxxxxxxxxx.xxx > Betreff: Re: [Doepfer_a100] A-156 input threshold tracking > > > 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, xxxxx@xxxxxxx.xx [Doepfer_a100] > <xxxxxxx_xxxx@xxxxxxxxxxx.xxx> 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: xxxxxxx_xxxx@xxxxxxxxxxx.xxx > [mailto:xxxxxxx_xxxx@xxxxxxxxxxx.xxx] > > > Gesendet: Freitag, 1. Juni 2018 19:33 > > > An: xxxxx@xxxxxxx.xx [Doepfer_a100] > > > Betreff: [Doepfer_a100] 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 > > > > > > > > > > ------------------------------------ > Posted by: John Hollis <xxxx@xxxxxx.xx.xx> > ------------------------------------ > > > ------------------------------------ > > Yahoo Groups Links > > > ------------------------------------ ------------------------------------ ------------------------------------ Yahoo Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Doepfer_a100/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Doepfer_a100/join (Yahoo! ID required) <*> To change settings via email: xxxxxxx_xxxx-xxxxxx@xxxxxxxxxxx.xxx xxxxxxx_xxxx-xxxxxxxxxxxx@xxxxxxxxxxx.xxx <*> To unsubscribe from this group, send an email to: xxxxxxx_xxxx-xxxxxxxxxxx@xxxxxxxxxxx.xxx <*> Your use of Yahoo Groups is subject to: https://info.yahoo.com/legal/us/yahoo/utos/terms/