GSSL HELP THREAD!!!

[beatnik]

So SPDT or not? 

About relay type would this work? The Omron Harpo suggested is going to be obsolete on mouser...

http://www2.mouser.com/ProductDetail/TE-Connectivity/V23079A1003B301/?qs=2waj4XMZKzfgpPKjhPMSqQtzoyAGB6ILnElx904QrhnN0v1lTUDGzw%3d%3d

Should I take the +15VDC before or after the regulator? And how do I calculate the dropping resistor? sorry for the noob question

 

[Harpo]

So SPDT or not?

Raw DC power to SP, relais to one of the DT with voltage dropping resistor in between, LED to either same throw or other side throw of your DT, depending on wanted display status (activated/bypassed) with separate current limiting resistors in between. Current return for relais and LED to transformers center tap. Flyback diode across relais coil.

About relay type would this work? The Omron Harpo suggested is going to be obsolete on mouser...
http://www2.mouser.com/ProductDetail/TE-Connectivity/V23079A1003B301/?qs=2waj4XMZKzfgpPKjhPMSqQtzoyAGB6ILnElx904QrhnN0v1lTUDGzw%3d%3d

yepp, but different housing and pinout.

Should I take the +15VDC before or after the regulator? And how do I calculate the dropping resistor?

There is no +15VDC before the regulator but (transformer secondary voltage times sqrt(2) - 2 diode drops)/2. For a maybe 2x15VAC or center tapped 30VAC secondary this will be about (30V*1.414-1.2V)/2=about 21V raw DC feeding each voltage regulator. Your 12VDC type relais has a coil resistance of 1029 ohms. This will draw about 12V/1029R=0.0117A=11.7mA at rated voltage. Your series resistor has to drop the 9V excess voltage (21V-12V=9V) with same current running thru, so will be about 9V/0.0117A=772 ohms. This resistor will need a rating of at least 9V*0.0117A=0.105W. Double up the rating, still a standard type 1/3W maybe 820R. Resistor for your LED might be (21V-1.9V)/0.01A=1910R. Pick a 2K with (at least (21V-1.9V)*0.01A=0.191W) 0.5W rating for about 10mA LED forward current.
Seem the easiest way, but YMMV. With some additional parts you could build it in a constant current config as well.

 

[beatnik]

Thanks Harpo! You did all the math for me.. I've learned something!

Just one more.. You mention that led and relay return goes to pt center tap.

I have a CRC board in between the power transformer and the gssl power supply.

Where exactly should I put the return for the relays (and take the raw DC to power them) ?

 

[Statherian]

Hello fellow DIY`s
ive just started my GSSL4000 build from Serpent.

"done" with sorting and checking the resistors.
but im not sure if its correct, its hard to find out witch way to read the resistors
so i was wondering if someone have written down how many different groups there is of the resistors, my count is 53 i think with the two big ones.
and a list of the values so i can see if i have read them the right way!

much appreciated for all the help, you will see me again

thanks in advance

 

[Harpo]

ive just started my GSSL4000 build from Serpent.

Welcome, but the 'SB4000 Support thread' might be the better place to ask for this build. This is the 'GSSL help thread'.

"done" with sorting and checking the resistors.
but im not sure if its correct, its hard to find out witch way to read the resistors

use your multimeter, set for measuring ohms, and measure the real world value of your resistors. If you don't have a multimeter, buy one. You'd need it at least for calibration.

 

[synnys]

I'm having problems turning my unit on, sometimes it goes on, sometimes only the panelmeter lights up, sometimes nothing at all. I always get the unit running eventually, but it's always a guess how many times i have to flip the powerswitch to turn it really on. Had this problem on multiple builds and i believe i'm not the only here.

I believe Jakob said a while back that it could have something to do with the different brands of 7815/7915. My guess is also that these components are the source of the problem.

Now i have read that some people used LM317/LM337 instead of the 7815/7915. I'd like to try that, but i don't know how to implement it, because i can't just replace the 7815/7915 with the LM's.

I someone could maybe 'draw' how i would wire the LM's (on a different breadboard circuit, including the caps/resistors/pots/trims?) onto the main board that would be awesome!

Or does anyone have a better approach to solving my problem?

 

[MeToo2]

I'm having problems turning my unit on, sometimes it goes on, sometimes only the panelmeter lights up, sometimes nothing at all. I always get the unit running eventually, but it's always a guess how many times i have to flip the powerswitch to turn it really on. Had this problem on multiple builds and i believe i'm not the only here.

I believe Jakob said a while back that it could have something to do with the different brands of 7815/7915. My guess is also that these components are the source of the problem.

Now i have read that some people used LM317/LM337 instead of the 7815/7915. I'd like to try that, but i don't know how to implement it, because i can't just replace the 7815/7915 with the LM's.

I someone could maybe 'draw' how i would wire the LM's (on a different breadboard circuit, including the caps/resistors/pots/trims?) onto the main board that would be awesome!

Or does anyone have a better approach to solving my problem?

Buy an off the shelf LM317 LM337 based regulator module ready-built off eBay, or a blank PCB. There's over 30 for sale there right now for less than 20 euros a piece including postage. The sample circuit on most datasheets is just fine. There's plenty of examples out there. Google and ye shall find. Just be sure to check the physical height of the large smoothing capacitors so that you're sure it'll fit in your case. You'll need to tap a point on the main PCB that gives AC out of the transformer (or use a separate transformer). You can then remove the 7815/7915 and rectifier diodes etc. and trace the ±15V lines from either the original AC terminal block on the PCB or the 1000uF smoothing caps, and you'll have to add in a couple of wire jumpers, but it isn't hard.

 

[synnys]

I'm having problems turning my unit on, sometimes it goes on, sometimes only the panelmeter lights up, sometimes nothing at all. I always get the unit running eventually, but it's always a guess how many times i have to flip the powerswitch to turn it really on. Had this problem on multiple builds and i believe i'm not the only here.

I believe Jakob said a while back that it could have something to do with the different brands of 7815/7915. My guess is also that these components are the source of the problem.

Now i have read that some people used LM317/LM337 instead of the 7815/7915. I'd like to try that, but i don't know how to implement it, because i can't just replace the 7815/7915 with the LM's.

I someone could maybe 'draw' how i would wire the LM's (on a different breadboard circuit, including the caps/resistors/pots/trims?) onto the main board that would be awesome!

Or does anyone have a better approach to solving my problem?

Buy an off the shelf LM317 LM337 based regulator module ready-built off eBay, or a blank PCB. There's over 30 for sale there right now for less than 20 euros a piece including postage. The sample circuit on most datasheets is just fine. There's plenty of examples out there. Google and ye shall find. Just be sure to check the physical height of the large smoothing capacitors so that you're sure it'll fit in your case. You'll need to tap a point on the main PCB that gives AC out of the transformer (or use a separate transformer). You can then remove the 7815/7915 and rectifier diodes etc. and trace the ±15V lines from either the original AC terminal block on the PCB or the 1000uF smoothing caps, and you'll have to add in a couple of wire jumpers, but it isn't hard.

thanks! just ordered a pcb for 8 euro's incl shipping.

 

[wthrelfall]

currently testing my 2nd gssl with much success, but i can't get my meter or power rocker switch to light up.  I'm using different components this time so can't use my first build as reference.  I've tried taking power from various places for my meter light (Behringer type, white led) but it just doesn't work.  I've used the forum search and followed previously posted instructions as best I can.  same situation for the power switch

 

[Harpo]

I've tried taking power from various places for my meter light (Behringer type, white led) but it just doesn't work. 

You had the appropriate current limiting resistor in series to your LED when trying ? else expect the LED to be blown.
Resistor value is the (supply voltage - LED forward voltage) / wanted (=<max.allowed) LED forward current, maybe (15V - 3.6V)/0.01A=1.140 ohms. A 1K2 should fit. Min.resistor rating would be (15V - 3.6V)^2 / 1200 ohms=0.11W. Doubling up the min.rating, you'd come up with an at least 1/4W rated resistor. If you don't connect between +15V and 0V or between 0V and -15V (for prementioned example values) but FI between +15V and -15V, the supply voltage number would change from 15V to 30V. Don't connect to the +/-12V rails.

same situation for the power switch

'the power switch' most probably will have a manufacturer and part-no. stamped on or you kindly could link to the switches datasheet, so we're talking on the same subject.

 

[synnys]

Can it be that the speed of flipping the powerswitch can actually cause the unit to have a hangup due to latching/locking VR's??

i found that the unit has more change to hangup when i flip the switch slowly than when i do it fast...

on my other build i used a push button switch and that unit never ever hangs at boot....

 

[dirtyhanfri]

Hi

After some time out of the studio I realized my gssl is giving me 0.5db less in one channel.

I tried to exchange the 5532s in the outputs but nothing changes. I was thinking in putting a 1k trimpot before the 15k resistor, after the vcas.

Would this be a nice solution? Or would be better to match some resistors? Wich ones?


Thanks

 

[Harpo]

I was thinking in putting a 1k trimpot before the 15k resistor, after the vcas.

1k trimpot in series to the 15k feedback resistor would work (...if the trimmers wiper doubtfully NEVER loses contact. Trimmer loosing contact while trimming or due to oxydation, the opamp will be running open loop, only limited by the supply voltage). Safer spot is to decrease the 27k in front of the VCA with trimmer in series.

 

[synnys]

I'm having problems turning my unit on, sometimes it goes on, sometimes only the panelmeter lights up, sometimes nothing at all. I always get the unit running eventually, but it's always a guess how many times i have to flip the powerswitch to turn it really on. Had this problem on multiple builds and i believe i'm not the only here.
I believe Jakob said a while back that it could have something to do with the different brands of 7815/7915. My guess is also that these components are the source of the problem.
Now i have read that some people used LM317/LM337 instead of the 7815/7915.
Or does anyone have a better approach to solving my problem?

Is there anyone who can help me with my problem?? I can't understand how my unit won't start up about 20% of the time...

i tried different switches, different brand VR's... how is this possible? i've read people having the same problem, and even solving it, but no one with a liable solution or explanation...

Harpo/Jakob? any thoughts on the matter?

Cheers!

 

[dirtyhanfri]

1k trimpot in series to the 15k feedback resistor would work (...if the trimmers wiper doubtfully NEVER loses contact. Trimmer loosing contact while trimming or due to oxydation, the opamp will be running open loop, only limited by the supply voltage). Safer spot is to decrease the 27k in front of the VCA with trimmer in series.

Ok, thanks, I'll try tomorrow, 1K is fine?

Is there anyone who can help me with my problem?? I can't understand how my unit won't start up about 20% of the time...

i tried different switches, different brand VR's... how is this possible? i've read people having the same problem, and even solving it, but no one with a liable solution or explanation...

Harpo/Jakob? any thoughts on the matter?

Cheers!

I'm having the same issue, always in the first time I turn it on, then when I turn it off and on again, it works fine the rest of the day.

I tried replacing the 78 & 7915's, different brands, and wiring them attached to the case via a isolated heatsink, they used to get hot  and there's no space to put heatsinks in the board, they're cooler now, but the issue keeps there.

 

[Harpo]

If a different brand of 7815/7915 (or 78L12/79L12) regulators doesn't fix it, this anti-latchup, parts (2x 100nF caps, 2 4x 1N400x diodes) fitted from traceside might help.
//edits see following posts for a latchup fix for all 4 rail voltages.

Ok, thanks, I'll try tomorrow, 1K is fine?

lots of ways to get there, but this probably not 1K trimmer question depends on your substituted value of the previously 27k. With all other parts perfect, the sum of previous 27k+trimmer value would be 25490 ohms to increase level by 0.5dB. 24k would be a standard parts value and a 2k trimmer/rheostat would get you to this 25k5. A 24k+1k trimmer obviously not.

 

[synnys]

If a different brand of 7815/7915 regulators doesn't fix it, this anti-latchup, parts (2x 100nF caps, 2x 1N400x diodes) fitted from traceside might help.

thanks will try it out, i already put two 100nf caps and one 1n4001 on the board, but on different places, found that in an italian forum... ill try this one also....

 

[synnys]

If a different brand of 7815/7915 regulators doesn't fix it, this anti-latchup, parts (2x 100nF caps, 2x 1N400x diodes) fitted from traceside might help.

didn't work for me any other tips?

 

[Harpo]

Regulator(s) hanging on startup is most often the +15V or -15V rail.
There are 4 different supply rails in this circuit. Measure all 4 rails (+15V, +12V, -12V, -15V) when startup fails and report back, so the culprit might be easier to identify.

 

[MeToo2]

If a different brand of 7815/7915 regulators doesn't fix it, this anti-latchup, parts (2x 100nF caps, 2x 1N400x diodes) fitted from traceside might help.

didn't work for me any other tips?

I don't have any immediate tips for you.
Can you take some voltage and current measurements in the working and non-working "hung" state?
Is it the 15V 12V, +ve rail -ve rail, all 4 that is affected?
What boards/mods do you have installed? GSSL? SSC? Turbo? dual SSC? RC anti-ripple? VU driver?
DBX black can VCA? DBX Gold Can VCA? DBX 2181 replacement circuit?
Additional relays? LEDS? VU lamps?

All I can say is that mine has never ever hung .

I have:
1) a large off board transformer for the ±15V AC (no on board transformer)
2) off board ±15V regulated supply based on LM317/LM337 for powering the GSSL main board + dual SSC filter boards + VU driver board.
I had this PSU board left over from a dual MNATS 1176 build
3) on main board ±12V 7812L/7912L regs for powering the sensitive side chain located on the main board + turbo sidechain board.
The 7812L/7912Ls are fed from the off board ±15V regulated supply.
4) another completely separate off-board ±12V regulated 'dirty analogue' supply hooked up to the same off board transformer, just for powering indicator lamps and relays. (I cut some tracks on the bottom of the SSC boards so I could power the bypass relays from a separate supply from the sensitive electronics)