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A-138b inverted output mod

A-138b inverted output mod

2017-08-02 by gleesonalan@yahoo.ie

Hi All


Looking at the jumper PDF there is a pin dedicated to "inverted sum output". I'm handy with a soldering iron but no good with schematics. I read a post on muffwiggler were someone mentioned they modded theres but didn't give details and it was a post from 4 years ago.


Anyone know how to add/mod an extra inverted output socket?


Thanks

Alan

AW: [Doepfer_a100] A-138b inverted output mod

2017-08-02 by yahoo@doepfer.de

At this pin header the inverted output signal is available for DIY
applications (upper pin = inverted output, lower pin = GND).
While we're at DIY: in addition a single pin is available for each input
socket (next to the socket in question) for internal normalling of the
inputs.

Best wishes
Dieter Doepfer
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> -----Ursprüngliche Nachricht-----
> Von: Doepfer_a100@yahoogroups.com [mailto:Doepfer_a100@yahoogroups.com]
> Gesendet: Mittwoch, 2. August 2017 12:27
> An: Doepfer_a100@yahoogroups.com
> Betreff: [Doepfer_a100] A-138b inverted output mod
>
>
>
>
>
> Hi All
>
>
> Looking at the jumper PDF there is a pin dedicated to "inverted
> sum output". I'm handy with a soldering iron but no good with
> schematics. I read a post on muffwiggler were someone mentioned
> they modded theres but didn't give details and it was a post from
> 4 years ago.
>
>
> Anyone know how to add/mod an extra inverted output socket?
>
>
> Thanks
> Alan
>
>
>
>
>

Re: A-138b inverted output mod

2017-08-02 by gleesonalan@yahoo.ie

Hi Dieter

Thanks for the information :) What I am attempting to do is add an extra inverted output socket. A socket has four pins, and I see these 2 pins, but I'm sure how to connect all the pins of the socket?

What I ideally need is someone to tell me "connect this pin on the socket to this pin on the board and this to this.....etc" ;)

Thanks
Alan

AW: [Doepfer_a100] Re: A-138b inverted output mod

2017-08-03 by yahoo@doepfer.de

I'm sorry - that's not possible. The socket has essentially only two pins
(GND + signal). The additional pins are only switching contacts used for
normalling. For details please refer to the A-100 DIY page on our website:

www.doepfer.com > English > PRODUCTS > A-100 > DIY page

You have to install an additional socket if you want to use the inverted
output. To be on the safe side I'd recommend to connect the signal via a 1k
protection resistor to the socket.

Best wishes
Dieter Doepfer
Show quoted textHide quoted text
> Hi Dieter
>
>
> Thanks for the information :) What I am attempting to do is add
> an extra inverted output socket. A socket has four pins, and I
> see these 2 pins, but I'm sure how to connect all the pins of the socket?
>
>
> What I ideally need is someone to tell me "connect this pin on
> the socket to this pin on the board and this to this.....etc" ;)
>
>
> Thanks
> Alan

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