GSSL HELP THREAD!!!

[hotbaby]

:'( :'(finished my second unit the last days and waited for a replacing a wrong part (79L12).
Audio passes the gssl.
Meter and threshhold works fine

makeup does not work and
theres no audible compression.

I checked a similar thread here and did these checkes too but there seems to be a problem on a different point.

I had a 78L12 instead of an 79L12 in there. Could it have damaged any party?
Any one has an idea where i should start searching for?
thanks for every help.
aaron

 

[kambo]

when the controller board is not connected to main PCB, is the audio in/out ratio mole/less 1:1 ?

power it off and replace the sidechain 2180/81 chip with one in the VCA, see any changes..
if one channel goes down then your sidechain THAT is burnt...

but most likely, your bypass lorlin is not wired correctly...

 

[hotbaby]

hey kambo,
thanks for replying.

If i deconnect the controller pcb the volume stays on same level...
i have no sidechain board installed and no bypass lorlin.
i just connected com to on and bridget  the bypass holes.

I exchanged the thats, they are working ok...

 

[kambo]

If i deconnect the controller pcb the volume stays on same level...

did you measure the input V and output... because if you have fault on your output you wont hear by ear.

so measure with your DMM in and out, with and without controller board connected.

if you have no bypass lorlin... then make sure

you need to short A - A2 connection on controller board... makeup gain "on"
you need to short C2 and Com "comp in"

check from connection diagram pdf file....

you are doing something wrong there...

 

[hotbaby]

ok i checked the xlr output + with and without the controller board. both stays on 0,04v  in every change.
I noticed that the sound is spreaded like a wide effect... something with the phase...
the xlrs are connected right and the hammerfall setup is right too
maybe this wide effect is known with this problem...

 

[kambo]

your +/- connectors are most likely wrong way around....

in and output have different molex pin connection on main PCB...

 

[hotbaby]

perhaps i am blind to see something that is wrong.
Here are hq pics:
http://img200.imageshack.us/img200/7231/img3248u.jpg
bypass connetion
http://img30.imageshack.us/img30/6759/img3247d.jpg

 

[hotbaby]

... i thought it too but the wiring seems to be correct:
http://img188.imageshack.us/img188/1908/img3249d.jpg
hmm...  :-\

 

[kambo]

pics looks fine...

disconnect the turbo board,
and run the PCB with its original spec... your turbo board connection missing a 47k... deal with that later...

EDIT : ohhh 47k in shrink tube ....

 

[kambo]

btw, looks like you have the lorlin  for the bypass... in that case you dont need to make short on pcb for comp in/out ...

 

[kambo]

on main PCB pic....

47k seems wrong... yours look like  starting with "red" value of 2xxx ?

send 0.775V 1khz to input
measure pin 1 and pin7 on 5532(output IC) , and measure output on molex...
change makeup gain and measure again...

do the same measurements without the controller board.

EDIT : 47k next to the ( top of the molex on pic) output MOLEX connection...

 

[hotbaby]

ok i will figure this out now. thank you 

 

[hotbaby]

i measured:
VCA 5532 on pcb border:
2,31vac makeup down and 2,79vac full makeup
the second output VCA 5532 right to the pcbconnector is:
2,34vac makeup down and 2,84vac full makeup

does it say something to you?

the 47k´s are allright. it is brown/red/black/pink/yellow.

turbo board disconnected now.

 

[kambo]

i was writing this while you re writing back but gain make up  should make around 5V difference...


basic signal test... i dont have the adjustable signal generator handy, basic one has only stepped V out.. buy anyway, to give you idea...

1khz sine wave 0.713V input ( measured between pin +/- at PCB)

controller board not connected...
5532 output IC
measured between pin 1 and pin7  = 0.750V (-0.3db)
pin 1 to ground  = 0.370V
pin 7 to ground  = 0.370V

controller board connected :

measured between pin 1 and pin7  = 0.754V (-0.2db) gain pot at min
measured between pin 1 and pin7  = 5.87V (17.6db)   gain at max

measure the XLR connections too.... measurements should be close to pin 1-7 readings...
if not, check the resistors around....

if you have little gain at max setting on gain pot, again check the resistors around output....


most likely, you have installed some wrong resistors... you will figure it out soon

 

[kambo]

one more thing :
set your DMM for DCV reading....

measure ground to wiper of your gain pot...
play with gain pot, you should have reading between 12DCV to 0 DCV reading...
that control DCV goes to TL072

ground to pin 7 of  TL072 you should read between 2.146 DCV to 0 DCV

if not, controller board connections are wrong... or TL072 is burnt...

( my measurements are for guide... dont have to be exact... but similar)

EDIT : circuit works without TL072, but the gain control and some other controls doesnt work.... audio passes no problem....
it might be TL072 in your case....

 

[hotbaby]

thanks kambo, i didnt got an email that you have posted new messages i will figure your/my values out and write it back.
thanks

 

[kambo]

no prob...
gain control Volt carried by "pin E" to main PCB ==== to  TL072 btw... check all that points too...

 

[hotbaby]

near the TL072 the Resistor  100K was 10K. Very hard so see the different as they differences only on the orange stripe that is a little darker on the 10k...
i replaced it and recognized that the music sounds distorted... all my two VCA THATS are death... i put in the one of my turbo board and the one under the big TL074. Both channels are working. Compression is working if i put in a working THAT in place under the tl074...
do you think could the 10k blow the THAT´s away? or was it already a death bought part?
maybe it is worth buying the 2181 instead of the 2180LB´s... or just two for the vca section?

without your help i didn´t think that i had sorted out this bad bad errors... puhhh
ill go to bed now   thanks
aaron

 

[kambo]

near the TL072 the Resistor  100K was 10K. Very hard so see the different as they differences only on the orange stripe that is a little darker on the 10k...
i replaced it and recognized that the music sounds distorted... all my two VCA THATS are death... i put in the one of my turbo board and the one under the big TL074. Both channels are working. Compression is working if i put in a working THAT in place under the tl074...
do you think could the 10k blow the THAT´s away? or was it already a death bought part?
maybe it is worth buying the 2181 instead of the 2180LB´s... or just two for the vca section?

without your help i didn´t think that i had sorted out this bad bad errors... puhhh
ill go to bed now   thanks
aaron

i think it could... its in the control of the 12 DCV for make up gain ...
experts will explain it better than me

glad, you sorted your problem anyway

kam

 

[damien]

Hello,

I wanted to know what kind of wire do you use to connect the different connectors to the boards (AWG size, strand number, solid or multi, brand...) ?
What size are the holes for wiring on the G-SSL boards ?

I bought this morning some black standard hookup wire 22AWG solid strand. It's quite rigid, and I think it will break easily. Do you think I went wrong with this ?

I'm really a newbie so, this question seems to be a bit dumb but for me it's not



Thank you for your help

Damian