GSSL HELP THREAD!!!

[Alessio]

Yes are the same switches. I'm in NYC so 120V.
on the switch is written: 250V AC 5A
I'll use 1 for the "power" and one for the "bypass". I'll use 2 SSC boards so the switch will control the relay!

Thanks Harpo!

Alessio

 

[Dazazone]

Oh no, I jumped in the deep end with my first gssl build.  I did a turbo with 2 x ssc.  It is finished and wicked, everything is great except for my meter.  Originally I put a Sifam AL19B but it was VU not 1 mA FSD.  I orderend the correct 1mA Sifam 19B and wacked it in.  It works! Just one problem though, when the power is on and compression is engaged with no audio signal present, the meter is pinned backwards.  It reads -10.5mV DC.  When I power down or in Bypass mode the meter returns to the zero point.  When I compress the meter reacts like you would expect and I have calibrated the -10db point as half way, but I'm not sure if it's correct at zero where it has to travel a couple of mm first. Any ideas anyone of how my meter is 'scared' of compressing, like when you have to jump from the 10m diving platform but then you get back from the edge and then someone pushes you in.
I'm thinking in between the bypass points somewhere  ???
Any help would be muchly appreciated!
thanks

 

[Dazazone]

Anyone else have this problem? I searched without success!  :-\

 

[Harpo]

I searched without success!   :-\

? posts from member Kent and reply from Jakob/Gyraf seem related. pg.2,3,4 from this thread. There are other ..

 

[Dazazone]

Thanks Harpo but that is a different issue from mine.  I'm talking about the voltage between the sifam meter + and - pins not regulator/ic voltages.  Sorry I know non-researchers are the anti-christ around here but I really have tried to find this issue, anyone with light to shine?  (please)
I'll do some testing for the source, yr prob right Harpo, maybe it is a funny ic.  :

 

[Harpo]

I'm talking about the voltage between the sifam meter + and - pins not regulator/ic voltages.

So do I. Might be a leaky 22uF cap @ pin7 of TL074, a broken or polarity reversed diode in the following rectifying or ratio stage or a broken sidechain VCA.

 

[azone]

anyone know if DBX C1252H2's VCA's can be used instead of the 202c or 2150's? any other changes required?
I've got a few dozen of these in my junk pile..

 

[ilfungo]

Ciao
someone can tell me which toroidal I can buy from Mouser  ?
I did order them all ....
thanks

 

[regularjohn]

Ciao
someone can tell me which toroidal I can buy from Mouser  ?
I did order them all ....
thanks

I generally use 25VA transformers with dual 15V secondaries.  Digikey seems to keep a better stock of power trafos.

 

[Harpo]

anyone know if DBX C1252H2's VCA's can be used instead of the 202c or 2150's? any other changes required?
I've got a few dozen of these in my junk pile..

Slaugthered noise reduction units? Should work, but some slight changes needed.
Increase 3K9 resistor between sidechain-VCA pin5 and -supply to 4k7 for bias current 2mA (DBX2150 is set for 2.4mA = (12V- 4*VBE drops)/3K9), same resistor to 6k2 in the 15V substitution circuit,
decrease the (1M+10k) connecting to VCA pin4 in the substitution circuit to 120k and 50k trimmer to 20k for THD adjust.
In the substitution circuit you might increase the 1k connecting to pin3 of the attenuator buffer NE5534 for the slightly typ.increased sensivity -5.9mV/dB instead of typ.-6.0mV/dB if it helps better sleep.
Just my 2ct.

 

[azone]

Slaugthered noise reduction units?

I think the boards are from Tascam 244 4-track, got a lot of mileage from the parts in that thing.

Thanks for the notes!

 

[Dazazone]

All working now thanks Harpo.  I ripped up the main board and found that I had accidently solder joined points C and B.  No fried components.  Now I'm getting 0.0033% THD and 104.5db noise floor on mainboard channel and 0.0166% THD and 104.6db noise floor on turbo board channel.  Is this ok or should they be a bit closer?
Thanks
Dz

 

[beatnik]

Hi everybody!

I need some help with my GSSL built from gyraf project. The clone isn't passing audio but the power section seems to be fine as the led lights up and the voltages from regulators seem to be ok.

Here are my voltage readings on the opamps, with no input signal. Please help me finding where some errors could be.

L&R inputs NE5534

pin1 -- 11,97
pin2 -- 0
pin3 -- 0
pin4 -- -15,09
pin5 -- -0,63
pin6 -- 0
pin7 -- 14,46
pin8 -- 11,96

L&R outputs NE5532

pin1 -- 13,76
pin2 -- -0,05
pin3 -- 0
pin4 -- -15,10
pin5 -- 8,10
pin6 -- 9,34
pin7 -- -13,86
pin8 -- 14,45

NE5534 on VCAs

pin1 -- 11,62
pin2 -- 0
pin3 -- 0
pin4 -- -15,12
pin5 -- -0,89
pin6 -- 0
pin7 -- 14,45
pin8 -- 11,65

TL072 & TL074 (some pins change voltage depending to the threshold pot)

pin1 -- -0,09 to 3,13
pin2 -- 0
pin3 -- 0
pin4 -- -12,18
pin5 -- 0
pin6 -- 0
pin7 -- 0
pin8 -- 11,89

pin1 -- -0,14 to 0,20
pin2 -- 0
pin3 -- 0
pin4 -- 11,89
pin5 -- 0
pin6 -- 0
pin7 -- -0,03 to 0
pin8 -- 0
pin9 -- 0
pin10 -- 0
pin11 -- -12,18
pin12 -- 0
pin13 -- 0
pin14 -- 0,22

 

[mitsos]

If you look through the thread, it seems most problems with these builds are solder bridges/shorts, or wrong resistors. I had some similar voltages on my 5534 pin 1's and VCA pin 1s, and it ended up being a solder bridge between one of the 47K resistors (going to sidechain) and the jumper next to it.  I then had another problem with it that also ended up being a solder bridge. So, check it with a magnifying glass, and/or check connectivity with a DMM. 
HTH!

 

[ncoak]

hey folks - working on my first gssl build. got the pcb from gustav, and was noticing there are some pads that are touching each other...the solder flows to the point of covering the entire pad pretty much every time, as a result the pads that are touching are soldered together - is this ok, or should i try again? appreciate any tips.

 

[ilfungo]

ciao
Can you tell me which switch I use to monitor simultaneously two super side-chain board?
thanks

 

[Harpo]

hey folks - working on my first gssl build. got the pcb from gustav, and was noticing there are some pads that are touching each other...the solder flows to the point of covering the entire pad pretty much every time, as a result the pads that are touching are soldered together - is this ok, or should i try again? appreciate any tips.

Crosscheck to schematic that these pads in question with corresponding parts are supposed to touch/connect. If so, all fine, else get a cutting knife, dremel or whatever handy to separate them.

 

[ncoak]

thank you, will do.

 

[Chrome Heart]

hey folks - working on my first gssl build. got the pcb from gustav, and was noticing there are some pads that are touching each other...the solder flows to the point of covering the entire pad pretty much every time, as a result the pads that are touching are soldered together - is this ok, or should i try again? appreciate any tips.

Crosscheck to schematic that these pads in question with corresponding parts are supposed to touch/connect. If so, all fine, else get a cutting knife, dremel or whatever handy to separate them.

There are quite a few pads that share a trace and they are supposed to be connected. As Harpo stated, double check the schematic and overlay for connected traces.

 

[Chrome Heart]

In case you dont have an overlay heres a copy.