GSSL HELP THREAD!!!

[Rockitdog]

Hi everyone. I'm wondering if anyone can help me?

I'm fitting the power transformer for my gssl and I'm a little confused as to the correct configuration. Looking at the guide on the side off the transformer, it does look very obvious. According to the key on the secondary I join the red and yellow wires (2-5) for the one 15v rail. And join the Blue and the grey together (7-9) for the second 15v rail? Right?

My question is, what about the 0v "center tap"?

The schematic also shows the center 0v rail going to ground. And every image I have looked at shows the center rail coming directly from the transformer. I cant find wiring configuration diagrams anywhere for this transformer. Do i need to configure it differently to get the 0v rail? But what color's do i join together to get 15 - 0 - 15??

(I know this is kinda obvious, just wanted to be super clear so its easier to help me) 

Can i simply run a ground wire from the center of the power pads on the pcb straight to the chassis ground? 

Or do I need to buy a different transformer? 

The answer is probably quite logical, I'm just nervous working with transformers (100% sure before flicking any switches). This is only the second one I am fitting and the first had a very clear wiring diagram on the side. I've also been wading through this thread for weeks and haven't come across anything specific enough to help me.

Please, if anyone can put me out of my misery it would be greatly appreciated. 

Thanks in advance

 

[Harpo]

Hi everyone. I'm wondering if anyone can help me?

I'm fitting the power transformer for my gssl and I'm a little confused as to the correct configuration. Looking at the guide on the side off the transformer, it does look very obvious. According to the key on the secondary I join the red and yellow wires (2-5) for the one 15v rail. And join the Blue and the grey together (7-9) for the second 15v rail? Right?

Probably noone can help you when your pics don't show up and you don't post transformers manufacturer and type or describe what the transformer attached label says. Transformer wires colour coding is not standarized.

 

[Rockitdog]

Hi everyone. I'm wondering if anyone can help me?

I'm fitting the power transformer for my gssl and I'm a little confused as to the correct configuration. Looking at the guide on the side off the transformer, it does look very obvious. According to the key on the secondary I join the red and yellow wires (2-5) for the one 15v rail. And join the Blue and the grey together (7-9) for the second 15v rail? Right?

Probably noone can help you when your pics don't show up and you don't post transformers manufacturer and type or describe what the transformer attached label says. Transformer wires colour coding is not standarized.

Strange. Images work fine on this side.
I've moved the image url's to a different location. Perhaps they will show now. I've also uploaded an image of the attached label.
Sorry, i really did think that the images posted fine.

 

[Harpo]

According to the key on the secondary I join the red and yellow wires (2-5) for the one 15v rail. And join the Blue and the grey together (7-9) for the second 15v rail? Right?

Join wire 5 with 7 (yellow+blue) for the center tap connection, going to the center pin of the 'External AC-In' on pcb. Wire 2 (red) to the adjacent AC pin, wire 9 (gray) to the remaining other AC pin on pcb.

 

[Rockitdog]

According to the key on the secondary I join the red and yellow wires (2-5) for the one 15v rail. And join the Blue and the grey together (7-9) for the second 15v rail? Right?

Join wire 5 with 7 (yellow+blue) for the center tap connection, going to the center pin of the 'External AC-In' on pcb. Wire 2 (red) to the adjacent AC pin, wire 9 (gray) to the remaining other AC pin on pcb.

Harpo! Once again. Thank you!

 

[ilfungo]

Thanks MeToo2!!!
thank you, you do not you treated me like a fool
and now I understand....
Thanks

 

[djvibe]

Would someone be able to post a photo of the grounding scheme of the GSSL? I am a bit confused as to what goes where. Also where is a good spot to have the chasis ground? Any help is greatly appreciated. Thanks.

 

[Olegarich]

If I'm not wrong, you want to have a star grounding in gssl. From your 220 you solder ground cable to chassis and all the other ground "points" (xlr's pin1, pcb) goes to the same point. I did it in my build and it's works perfectly, no hum, no noise ground issues.

 

[Gustav]

Would someone be able to post a photo of the grounding scheme of the GSSL? I am a bit confused as to what goes where. Also where is a good spot to have the chasis ground? Any help is greatly appreciated. Thanks.

Check the manual on my site - it covers the grounding

https://pcbgrinder.com/index.php?route=product/product&path=60_74&product_id=50

Gustav

 

[djvibe]

Love the new manual!

 

[Maxolomeus]

Hey guys, I almost finished my GSSL basic build (turbo and SSC are to come) and fired it up today.

Voltages are totally fine, every ICs get's its correct values. Input and Output of VCAs are bridged at the moment (don't wanted to insert my 202C at the moment) and the Unit ist passing audio without problems (0,2V more on output than on input, but that's fine for me).

But my question is the following as there is no VCA yet installed the threshold knob and meter should work even without VCA, or am I wrong? Where should I measure on control board to be really sure that there's everything fine?

 

[nashkato]

hi
just fired up my GSSL build . it passes audio , treshold works and it seems to compress , but neither the meter (sifam director 24A , 1ma) nor
the makeup gain works .
where should i start looking ?

thanks
just found my mistake  i swapped to cables on the 10 pin connector to the frontcontrols

 

[Harpo]

just fired up my GSSL build . it passes audio , treshold works and it seems to compress , but neither the meter (sifam director 24A , 1ma) nor the makeup gain works .
where should i start looking ?

First check is psu (for any build using active components). Are your +/-12V rails working?
Bypass switch wired correctly? If you use a trimmer for your meter instead of a fixed resistor, is trimmers initial value set about centered?
Else the usual suspects. Look for shorts, parts values and parts orientation.

 

[fripholm]

Hi guys,

I'm new here and today I've finished my first Gssl. After a few hours of troubleshooting it's even passing audio on both channels. As I'm pretty new to electronics this was a great success. Unfortunately it's not yet compressing the audio signal. 

Accidentally I've found out that when I touch the back of the control board with my fingertips (where the 10 cables from the MB connect), the GR needle moves and the audio gets softer. My fingers seem to regulate the VCA's control voltage. The Bypass Switch and Makeup Gain are working as expected in this case, even the Attack and Release settings seem to make a difference when I touch the board (i.e. the GR gets slower or faster).

It's like some component from the sidechain does not get the incoming audio signal but I really don't know where to look for possible errors. I've tried to search the forum but didn't find something...

Any ideas?

 

[fripholm]

^^^ anyone?

 

[Aniol1349]

Hey guys!

I have finished my second GSSL and I have a strange problem with the meter.
I don't have really extended knowledge in electronics but looks like problem with capacitors.

The problem doesn't appear every time, sometimes it power ups fine.

so, when I hit the power button the meter needle starts to load up and stops in the middle of the meter, then when I hit the power again I get that bang and the LED lights up for a second and the meter goes crazy, I guess the caps are releasing the charge. Then I hit power again and it works fine.

http://www.youtube.com/watch?v=It5ZqWD-vwY&feature=youtu.be << here is a video I made of the meter so you can see how it looks like.

Any idea where I could look to solve this problem?

Cheers!

 

[djvibe]

Does anyone have instructions or a guide to voltage testing for the GSSL. We have finished building the PCBs and want to test everything before switching on the transformer. Any suggestions? Thanks.

 

[gyraf]

Aniol1349,

You probably have the powersupply latch-up problem described before. Check your +/-12 and 15V's.

djvibe,

The standard way is to visually check pcb track side for shorts, ENSURE that every IC is oriented correctly (specially the vca's) then powering up and measuring +/-15V at the 5532's and +/-12V at the TL074.

Jakob E.

 

[fripholm]

Hi folks,
I've finally managed to get it working. YAY!!!!  8)

I had a PCB rev#11 from pcbgrinder which has a connector called "* HPF" for which I did not find any documentation. I only had much older schematics to work with. After lots of re-soldering, looking for shorts, replacing ICs, tracing, searching this thread etc, I've decided to replace all the caps in the sidechain and while doing that I found a 22 µF on pin 7 (TL074) which was connected to - well - nothing... Looking at the schematics this had to go somewhere - et viola - that's it!

Before starting this project I would've not been able to read schematics at all - thanks to this thread, I could at least hunt down this missing bridge. Thank you all!

Now let's compress something  ;D

 

[Aniol1349]

Thanks Gyraf!

found some info in the thread already..just didn't know where to start looking for it that's why I asked.

Cheers