GSSL HELP THREAD!!!

FarisElek said:

..This is the power transformer I'm using:
https://www.mouser.com/datasheet/2/410/media-1067232.pdf

(I'm 115v US)

Right now I have:

1) Hot on the IEC going to a switch which goes to BLUE+VIOLET
2) Neural going to BROWN+GREY

Click to expand...

You are missing a fuse, maybe built within the IEC inlet.
Connection of transformer primary wires looks correct.

which leaves me with 4 secondary wires
1) Jumper BLACK+ORANGE
2) Jumper RED+YELLOW

Now how do these attach to the PCB? I see of the 5 PSU PCB holes , the middle one goes to ground and that the two on each side are connected. Does that mean i don't need to jumper and I can just put BLACK and ORANGE on one side, and RED and YELLOW on the other?

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No! You don't want a parallel connection for a single 15VAC feed. You want a series connection with a tap in the middle.
The PSU for the GSSL wants to see a 30VAC CT (center tapped) transformer secondary feed.
For your TRIAD transformer (other brands will have a different colour coding) this is done by joining red with orange and taking this junction (maybe with another piece of wire) to the center pin (pin-3) of the AC inlet on pcb. The 5 drill holes on pcb allow for a 3-pin connector with either 0.1" or 0.2" pin-spacing. The outer pins (pin-1 or 2) or (pin-4 or 5) connect to the black wire for one and the other to the yellow transformer secondary wire.

good luck

Thank you! That is very helpful. Besides wiring a couple things (including the pay). I’m completely done. I really hope nothing goes array.

Everything is wired up except a couple things here and there. But my last question (I think), is how do I wire the bypass for toggle? If I'm understanding this correctly, I'd wire the 3 poles of my toggle to Com, On, and Off, and then the "wires to bypass sw or link on pcb" I jumper together those holes if I'm not using a pot?


Ryan

Update: answer found on page 245 finally. Or maybe it was 225. One of those two posted Harpo.

Welp, just turned on the GSSL for the first time and got some serious smoke on the mainboard. Had a DMM on the +15vdc while it was powering up so that I could watch the voltage. I turned it off immediately when there was smoke and the +15vdc rail at that time hit around 25vdc when It started to smoke/I turned it off. I'm fairly certain what smoked was the 10ohm resistors on the PSU. I wired Black to pin 1, Yellow to pin 5, and orange + Red to pin 3.

I measured the voltage on each pin without it attached and it was giving me:

Red + orange = 10.86AC
Yellow = 2.4AC
Black + 25AC

What's going on?

Ryan

you must be "holding it wrong"

Have you read through this thread, specially at the places about how to measure voltages?

Reason for asking is that if you have voltage on Red + orange, it indicates that you measure wrong

Remember, measuring with a multimeter involves it contacting two points, one reference (usually black lead) and one hot (usually red lead)

In the GSSL (as in most electronics) it is convention that you measure from/relative-to 0V, when nothing else is explicitly mentioned.

And the 0V IS actually your Red+Orange, which leaves no room for your measured 10.86 Vac at that point.

Check thoroughly and try again?

/Jakob E.

I had the black on IEC ground. I thought that was sort of a universal ground. But I guess not, because when I have black on the center tap I get 17.5v on both black and yellow.

What could I have done wrong then?


EDIT: Oh sheesh....Realized the side chain VCA, and the two 5534 IC's in the VCA were not positioned correctly...
Fit them the correct way and It's working but no compression. Guess the IC's and VCA's are toast?

That was almost my first time no problems perfect build  :-\

Also, to be thorough, do I need the 50k trimmers mounted in the VCA section? I'm using THAT 2181LB in all 3 positions.

If using the 2181LB in the side chain position, so I need anything particular in the resistor marked %? I didn't find anything about that in my searches.

Thank you much,
Ryan

Sorry to be so persistent but...

I just

1) changed the 2181B's out of all 3 VCA spots
2) Changed all 5532 and 5534 opamps out for fresh ones.
3) Checked continuity on all wires from main board to panel board.
4) Went over every single solder point, although they were looking good before.
5) Went over areas were there may have been solder bridges.
6) Checked +/- 15 and 12v rails and I'm getting perfect voltage within .25 v on both.

I am getting perfect audio playback. I have plenty of make-up gain.

I am just getting no compression whatsoever.

Could it be that the TL074 is toast from when I accidentally had the side chain VCA and VCA 5534's reversed?

I do not know what else to check besides maybe the 1N4148's.

Here is a picture of my board if perhaps anyone notices something out of place.

FarisElek said:

6) Checked +/- 15 and 12v rails and I'm getting perfect voltage within .25 v on both.

Click to expand...

both would be 2 voltage rails. The GSSL has 4 or 5 voltage rails (+15VDC, -15VDC, +12VDC, -12VDC, maybe aux +12VDC).

I am just getting no compression whatsoever.

Click to expand...

No wonder without the HPF provision either jumpered or HPF setting cap fitted...

Here is a picture of my board if perhaps anyone notices something out of place.

Click to expand...

Only half of the audio output is connected...

Harpo said:

both would be 2 voltage rails. The GSSL has 4 or 5 voltage rails (+15VDC, -15VDC, +12VDC, -12VDC, maybe aux +12VDC).
No wonder without the HPF provision either jumpered or HPF setting cap fitted...
Only half of the audio output is connected...

Click to expand...

Yes, sorry about that I meant +/- 15 and +/- 12. I meant for it to be implied.

Only half the output is fitted because I wanted to make sure it worked before I finished crimping all those annoying little crimps.

So wait, I thought the hpf was only if I had a side-chain board. Do I just jumper across it?


EDIT: Ah jeez. Looks like jumping the HPF worked immediately....haha. Guess I have to read into this HPF more, I wasn't aware there was one built into the circuit and I was under the impression I needed a separate board.
If anyone has any recommendations on how to wire a HPF switch to a capacitor, and what capacitor I'd use for an 80hz or so cut, i'd very much appreciate that.

Thank you Harpo! I'm not a complete noob (just kind of one), but I still make complete noob mistakes!

You just made my entire week.

Best wishes,
Ryan

recommendations on [...] what capacitor I'd use for an 80hz or so cut, i'd very much appreciate that.

Click to expand...

Could use online RC filter calculator

hi, i have finally mounted that2181c on my pcb "rev7".
I have read somewhere that you have to make a modification to some of the resistances that are around you, for example the 3k9 resistor must be replaced by a 5k1 resistor, the 10k resistor must be put on a jumper, and the 68r must be removed, also another change in the bottom of 1m change it for 130k.
Can someone confirm that this is all correct?
thank you

Juanaca said:

hi, i have finally mounted that2181c on my pcb "rev7".
I have read somewhere that you have to make a modification to some of the resistances that are around you, for example the 3k9 resistor must be replaced by a 5k1 resistor, the 10k resistor must be put on a jumper, and the 68r must be removed, also another change in the bottom of 1m change it for 130k.
Can someone confirm that this is all correct?
thank you

Click to expand...

http://diy.fischerworks.com/gssl_vca.shtml

Use this but follow the silk for everything that he lists at “?”.

Ryan

hello good evening i just finished mounting my gssl 4000 rev7 with that2181c.
sound enters and exits without problems, all the voltage measurement seems correct, but the control panel only works the led, the other controls do not respond, it is as if it were in a continuous bypass.
I have a push button as a bypass, connect as follows.

push button COM pcb hole
pcb ON hole in pusher NC
pcb OFF hole in NO of the button.

I don't have much idea of electronics and I'm stagnating at this point.
thank you

I'm stagnating at this point

Click to expand...

So is your signal.
Read schematic and thoroughly check traces for continuity.

Bypass is two switch parts, one shuts off gainreduction, the other shuts off makeup gain.

You should probably try reading this thread - it is unlikely that you have a problem that we havent seen and solved before..

/Jakob E.

thanks gyraf I reviewed the entire circuit as you advised me and discovered that I missed a 1k resistor, novice failure.
Now it goes well compressor, I notice that it does not compress excessively with the ratio 10, short attack and short relase. I would like it to saturate a little more, but I am satisfied, it has good sound.
I have a last consultation to see if they can help me, I have searched and I cannot get much information.
I want to put buttons on bypass, ignition and sidechain
The push buttons that I have bought are 220v, do I have to set relay to 220v?
is the use of relay mandatory?
Could someone put an outline of how to make these connections?
I know it is valuable information, we have to take time to do it, but many doubts will be resolved.
thank you.

Juanaca said:

I want to put buttons on bypass, ignition and sidechain
The push buttons that I have bought are 220v, do I have to set relay to 220v?
is the use of relay mandatory?

Click to expand...

They are not 220V. That's the switches max. rated voltage in either AC or DC current. Depending on your location (please update your profile) and if this pushbutton should switch the AC mains voltage, this maybe 220VAC rating might be sufficient, if the current rating fits as well. As long as you don't exactly specify your type and model of switch (FI Mouser alone is offering 71618 different pushbutton switches ,varying in lots of parameters), noone could seriously give advice on hookup. If the use of a relay is needed depends on the type of switch as well. For usual operation you want a latching pushbutton switch with at least two poles and two throw positions, one more pole if the switch is iluminated and you want to switch the ilumination on/off depending on wanted status. A switch with only a single pole and throw better would operate a relay that does the switching function with the amount of poles/throws needed for the GSSL and addon circuits.

Thank you very much for your answer Harpo, my electric current is 220v.
Attached the buttons that I bought, there were several options, 12v, 24v, and 220v.
I can't explain why I chose the 220v ones.
Asjojo link of the images and I would be very grateful if you could explain what relay I have to select and how it would be connected to the button.
thank you.

https://drive.google.com/file/d/19gOY2wvCRz3SGGoVkqKVys9Xwl-VUYzo/view?usp=drivesdk

https://drive.google.com/file/d/1Aoe9qZ43SxmdydPZBwYWyhxA2tyqMUh7/view?usp=drivesdk

Juanaca said:

Thank you very much for your answer Harpo, my electric current is 220v.

Click to expand...

...update your profile with your location data, so it would be easier for us to help you and you wouldn't be asked for the same info over and over again... Not only mains voltages differ when consulting an intercontinental forum...

Attached the buttons that I bought, there were several options, 12v, 24v, and 220v.
I can't explain why I chose the 220v ones.

Click to expand...

12VDC would have been the better descision, considering this 12VDC supply voltage is already on board just for this purpose.

https://drive.google.com/file/d/19gOY2wvCRz3SGGoVkqKVys9Xwl-VUYzo/view?usp=drivesdk

Click to expand...

From your pic, this seems to be a SPDT (single pole double throw) illuminated pushbutton switch,
looks a little like series PLP16 from C&K https://www.mouser.de/datasheet/2/60/datasheet-1729296.pdf
or series YB from NKK https://www.mouser.de/datasheet/2/295/ybilluminated-1663306.pdf
but both don't come with 220V AC-mains illumination (of whatever illumination type, incandescent lamp, neon, LED, with or without built in resistor, ...),
that's why I asked you for type and model of your switch.
Unfortunately you probably better avoid a switch with mains powered illumination in close proximity to sensitive control voltages in mV range.

https://drive.google.com/file/d/1Aoe9qZ43SxmdydPZBwYWyhxA2tyqMUh7/view?usp=drivesdk

Click to expand...

doesn't show up here...

... what relay I have to select and how it would be connected to the button.

Click to expand...

When you look at the GSSL schematic, for the bypass function you want a DPDT (double pole, double throw) switch, so you'd need a relais with at least these switching functions. You hook up the relays common pole and throw positions like shown in schematic. With a 12VDC operated relay, relay-coil+ connects to your probably center connection of your pushbutton switch. relais-coil- connects to 0V reference voltage. Place a flyback-diode (maybe 1N4004) across the relais-coil +/- connections, cathode side to the + end. Depending on wanted status (compressor bypassed or compressor activated when switch is pressed down), you connect the +12VDC aux supply rail from GSSL main board to either the NC (normally connected) or NO (normally open) switch contact. For switch illumination, you connect the same pushbuttonswitches center pole to the + connection of the switches illumination contact if there is a LED inside your switch. If inside is a (not polarized, but a power hog) incandescent lamp, connection side doesn't matter. (your 220V operated whatever it may be shining part will not show up with an only 12VDC supply). Other side of pushbuttonswitch illumination contact goes thru a needed current limiting resistor to 0V reference voltage if its a LED and the resistor is not already built inside the switch, or direct to 0V reference voltage for an incandescent lamp if you like it more bright.

Thank you very much for the indications HARPO, I am going to try to make the connections as you indicate, I do not understand all the electronic terms you use because I am a simple fan of electronics, I know it is a lot of work and annoyance but could you draw how all this would be connected?
I would not like to burn anything from the pcb, the simple fact that my compressor works right now is a miracle for me.
thank you