Lawo V982/1

Hi folks,
i just got a pair of Lawo V982/1 but don´t have the pinout. Can anybody help me out ?

i´m just too lousy at trial and error :-(

I was also wondering if the red cards which are mounted vertically are the 15KHz Filters. Is that correct ?

thanks in advance

Arne

the red card is a DOA.

I probably can't help you out, but maybe a schematic of the v976 will help?
I have a pair of V970 and used the V976 schematic to find out the pinout.

Here it is:
http://members.home.nl/matthijsblom/LAWO-V976-Schematic.pdf

thanks so far....

the 982 is a distributor (1 to 4). Probably there are units from Neumann, ANT or so which are identical ?

any hints ?

ok ok i got it - no wonder that nobody came up with further information since it is rather easy to find out the pin out

I´m sorry for being sooooo lazy

BUT: more problems occured.

- I did not find any audio ground so far, am I blind ?? Theres only one groundplane but I can´t believe that it is used for both 24V and audio ??
- Also this thing has a serious low-cut and overall attenuation of 10dB. Around 300Hz the attenuation is 20dB and gets worse below this.
  I did no find anything which looks like a filter (at least which looks like filters i know) so I´m wondering how to get rid of the low cut.
  Or do I have to use termination resistors at the output ? The analyzer i used has 10k input impendance...

So if anybody is familliar with this these things or has a schematic - please help me out

thanks
Arne

In doubt ask Lawo. Or post pictures here, maybe we can draw some conclusions from there.
Does it have 4 output transformers or are the outputs electronically balanced (typically for Lawo with a load of NE5532s)? How many DOAs? All Lawo cards have several ground connections at the output connector. There you connect PSU 0V with ground, have a look at it at kubarth.com
Did you connect a gain resistor? You probably (I´m guessing) need somewhere a gain defining resistor, look at the V972 schematic how the do it there. Maybe you can trace it down that way.
You mean Hi cut or Lo cut? There´s probably a broadcast filter at 15kHz to get rid of any pilot tone interference (19kHz) in the desk. That´s done with a simple cap, sometimes they use an inductor, too (which can easily be shortened). I´m not aware of any Hi pass filters in these modules. That´s naturally done by the sheer amount of all the trannies the signall has to pass in an analog Lawo desk. Maybe you thingy needs a recap?

hmm, theres only one capacitor per channel anywhere near the signal path. Goes from the Output transfo to ground. I changed it but no difference.
There´s also a little arrangement of cap (WIMA 2200uf) and something that looks like a adjustible cap - it has a little screw on it. I turned the screw but nothing happens.
This part of the circuit can be taken away from the signal path, there are jumpers for that. I tried that also - no difference.

I have two of these cards and both behave the same way. So I think it´s not a bug but a feature. For what reason I don´t know.

I´m  definitely interested in a schematic or any further hints.

I did measure, it is definitely a high pass filter not the usual 15KHz low-pass. In the diagram the blue line is the Lawo, the red line is my A/D Converter shorted with same signal.

Thanks so far