GSSL HELP THREAD!!!

[HappyTom]

[quote author="Jonathan Hayward"]Tom What's the voltage rating on the Behringers.[/quote]

I found a thread where Greg powered up his meterlight with 12 VDC but i can't find if he found out where to get the power for it in the clone.

HT

 

[Jonathan Hayward]

Any point at 12V DC should do on the circuit, it should have current to spare for a small bulb. There may even be a spare 'hole' available at that voltage you could attach the wire to (other side of the bulb to ground), if not, just solder the wire to the solder side of the pcb.

 

[gyraf]

Please do NOT use the 12V rails form the SSL-clone PCB for meter light, as there is not enough current for that - we're stabilizing the 12V's with 78L12/79L12's. Also, the 12V's are used for reference and we don't want any dirt in there...

For meter light it would be better to use unregulated supply voltage with an appropiate voltage dropping resistor (use Ohm's law..)

Jakob E.

 

[Jonathan Hayward]

well that told me didn't it!

 

[Svart]

I mounted a separate Vreg off the board especially for my meter and power lights. make sure you isolate it and ground it at the star.

 

[ChrisA]

I just built a 2nd ssl clone and went to power it up and immediately the LM7915 got way too hot...the unit does not appear to pass any audio either...so I shut it down.

Everything looks ok, but I'm going to check to see if there are any solder bridges on the pcb.

has anyone had this problem?

thanks guys

chris

 

[JayDee]

Just as an additional info for the SSLs "hanging up" during power on. In my clone it wasn´t only the 78L12 and 79L12. I also had to change the 7815. I think there are bad production series out there. After changing the 7815 I never had the power on hang up problem.

cheers
Jürgen

 

[pxpx83]

So I've been staring at my nearly finished ssl for a couple weeks now and I think it is finally time to finish it (now that the electricity has been turned back on after the hurricane). I'm not sure how to wire my bypass switch and relay. I want to defeat makeup gain when the compressor is bypassed. Here is a quick drawing I did of the layout:

http://img.photobucket.com/albums/v297/pxpx83/ssllayout.gif

Any help would be appreciated.


Thanks!

 

[Ian MacGregor]

Ok, sorry in advance for the horrible drawing! I just used paint to connect the dots. You will want to double check my work before you solder everything up!! The jmp is a jumper where the 1k current limit resistor for the power on led is. I jumper it so I can use individual current limit resistors for the LEDs. Hope this helps!!!

Ian

 

[pxpx83]

dude... you rock! I'll solder everything up and let you guys know the results.

Thanks!!

 

[ChuckD]

Where did my + rail go????

I had everything up and running but then all of a sudden I only see 3.3 VDC on the inputs of both 7815 and the 78L12.
This results in the +12 rail becoming 1.5 VDC instead.

Did I blow the diode bridge ? Is that possible?
Maybe one of hose big caps is screwy?


any ideas?

-Chuck

 

[gyraf]

Chuck,

- Check the bridge rectifier with the diode tester on your voltmeter.
- Check AC supply lines coming to the bridge rectifier.
- Check DC at the output of bridge.

- To check for possible shorted supply lines, cut the pcb trace going from the voltage regulator and measure voltage. Remember to repair the cut afterwards

Jakob E.

 

[daniel_c]

Hi guys ,

I've just about finished my G4000. All I need to take care of is the power and I have a couple of questions.

Im looking at getting a toroidal tranformer. (farnell 430-1389) Is a 30VA transformer over kill or should I get a 15VA?

Also , I want to double check the wiring of the transformer. Its a dual 115v primary , dual 15v secondary type.

Primary 1 has a blue wire and a grey wire , primary 2 has a violet wire and a brown wire. (there is a black dot next to the blue and the violet , that shows the start of the winding , right?)

Secondary 1 has a black and a red wire , secondary 2 has a orange and yello wire. (with dots next to the black and orange wires).
We are 240V here in Australia , so should I connect the blue wire to the active treminal , join the grey and violet wires , and connect the brown wire to neutral.

As for the secondary , should I join the red and orange wires and connect them to the centre of the PCB power in , and the black and yellow wires go to the 2 outside holes of the PCB power in?

One more thing.... as far as a fuse goes , would 100ma be enough or is it more like 1A?

Sorry for so many questions.

Thanks

Dan

 

[Svart]

from what you said, you have the correct idea on the primary and secondary wiring(both are in series). 15va is what i use and it's fine!

I would go with a 1 amp fuse. I put some lights in mine and it pulls about 1/4 amp.

and ask as many questions as you need! that's what this place is for!

good luck!
:thumb:

 

[ChuckD]

Thanks Jakob,

I put the diode mode on and looked at the rectifier and it seems ok!
I then left it in that mode and looked across the Voltaghe regulators. the results was puzzling, it indicated a short.

To confirm this I put the multimeter in Resistance mode and looked at the outputs on each voltage regulator to ground the 7915 gave 15-16Kohms while the 7815 gave 1.5 ohms.
This confirms that there is a short somewhere after the 7815 I believe.

I gonna try to find it.
Does that sound like the problem to you guys?

-Chuck

 

[Guest]

Gyraf,
can you please elaborate on the power and bypass led positions. I have the power led powered off the 1k resistor where it's supposed to go. Since +12v is coming from the top of that, what is the voltage after that resistor? I'm trying to find a 12V led and I'm beginning to realize that that's kind of hard, so I'm assuming there's some kind of voltage drop over that resistor. I know V=IR, but how would that be applied. I assume the other LED that I'd like to add for the bypass switch will just come off the +12V with a 1k resistor added like the other take off for the power LED.

Thanks,
Brandon

 

[Ian MacGregor]

Brandon,
Most LEDs will only drop 0.5-0.8V. You must use a current limit resistor in series to drop the rest of the voltage. Using P = IV and V = IR to make sure that the resistor is the correct wattage. For example, if you want to power a LED (assume 0.7V drop) from 12V, you need a resistor to drop the "extra" 11.3V. Say you use a 1k resistor. There for the LED will get 11.3mA current. Since P = I^2*R, the resistor dissapates around 128mW, which is well under the 250mW limit for 1/4 watt resistors.

Ian

 

[Guest]

So I guess I don't need to look for a specific type of LED or anything then? So why are LED's specified as 3v, 6v, and 12v at radio shack if they all just only drop 0.7V?

Brandon

 

[Ian MacGregor]

Hmmm... are you sure these are not lamps? Maybe they have an internal dropping resistor?? Do you have a link for these parts??

Ian

 

[gyraf]

Yep, as Ian says, use a standard LED, the voltage dropping / current limiting is taken care of by the onboard 1K resistor.

Yes, you can get LED's with internal resistor for certain voltages, but we use the plain no-resistor type here.

Jakob E.