9K PSU transformer question/problem

[RedNoise]

 

[MartyMart]

[quote author="RedNoise"][/quote]

No need for the at all

Same applies if you attach both to the case, they need to be insulated from case
and each other.

MM.

 

[RedNoise]

Hey guys ,
may I ask if I should put in common both 0V of the 2 psu???(pcb insulated of the case)
I ask this cause there's no 0V on the preamp pcb , regarding the +/-15v.

 

[geoff004]

thanks for all the help.

has anyone used an Antek transformer for this project?
maybe this one:
http://www.antekinc.com/AN-0222.pdf

I don't quite know how to figure how big the thing needs to be. The price makes it attractive.

 

[mitsos]

That's the one I have. It's working fine, which is more than I can say for the rest of the preamp! Seriously having other problems, but the transformer is fine. It depends how many channels you're doing.

 

[Di_Sousa]

I'm really sorry if I'm dumb,

But why all this talk about the +/- 15v on the SSL 9k project?

I read the part explaining that Tl052 use 15v, and its also written in schematic.
I also read in this thread that TL052 max supply is  +/-18v.

If the tl052 had to work at +/-15v why would Keith do a power supply circuit with onlu +/- 18v?
Why would we be buying pcb from gustav that only supply 18v , when they could be easily changed for 48v, 18 and 15 v?

it doenst make sense to me. Is this real or just for the higly cautions people?

sorry if all this questions are dumb

 

[MartyMart]

Whoops = your in box is full so I can't reply to your PM's !!

Re the SSL 9k
Circuit is designed to run at +/- 18v and needs the TL052 section which also needs
+/- 15v rails too.
You can either :
Have two sets of PSU boards/ rails OR from the 18v rails use dropping resistors, three 4001's in series with
each rail would do ... watch the polarity though !!

Marty.

 

[Di_Sousa]

COOL

I understood now why there were no changes made in the PSU PCS or the main Board, its because you can easily put some diodes or drooping resistors between the 18v in an the 15v in without having to alter anything else.

quite an easy solution

thanks Marty,
by the way , I emptied my PM box

 

[SNG]

Have strange voltages after building the SSL9K PSU....

+18V is correct
-18V is shown as -29V
48V is shown as 43V

when placing a 3K9 load resistor between -18V and GND, then -29V drops back to -17.9V, that's okay then....
do the same with the 48V and nothing changes

all parts are correct, I think...
- W04 Bridges
- All elec.caps are from Rubycon
- 100 nF caps are Kemets 63V
- L7818CV/L7918CV/LM317T from StMicroelectronics
- torodial transformer 25V-0V-25V, 50VA

is 43V normal or do I need a different resistor to test it out?
and can it harm when the -18V gives -29V unloaded for a whilte.... will it not burn the regulator after a while?

 

[mitsos]

Are you using 240R / 8K2 for the LM317 adjustment? Change the 240R to 220R.   

 

[Harpo]

"when placing a 3K9 load resistor between -18V and GND, then -29V drops back to -17.9V, that's okay then"
a LED with series resistor for maybe 10mA LED current (1K6) will do the same and might be a handy indicator for power ON.

"48V is shown as 43V"
with values from schematic, its quite normal and most condensers will work well with this voltage. Changing R2 from 240R to 220R will/might get you closer to 48V  [1.25V*(1+R1/R2)=47.84V]. This typical 1.25V reference voltage can be in range between 1.2V and 1.3V and resistor tolerances might size it up or down a little. When changing this R1/R2 network to increase output voltage, make sure you have at least 3V above your target voltage in front of your regulator.

-Harpo


oops late, mitsos was faster again...

 

[mitsos]

yeah, but looking at it, I could(should) have given a bit more of an explanation...  :-\

 

[SNG]

Thanks for that golden tip to change the resistor to 220 ohm.  ;D
Just change it and have now on the point 48V of phantom power...
time to start-up my SSL9K pre-amp now for the first time..... exiting...  ;D ;D ;D

 

[xqqxqq]

I have a SSL9K channel strip, I do not know how to give it power, I ask, SL911 What power?+18 -18-24 +48 ？how to connect to the pin?
SL911 audio input and output to connect?
Thank you!

 

[Di_Sousa]

I have a SSL9K channel strip, I do not know how to give it power, I ask, SL911 What power?+18 -18-24 +48 ？how to connect to the pin?
SL911 audio input and output to connect?
Thank you!

Hi,
you should start your own thread about this.

publish some pics of the strip and connectors

getting the schematics would be the first step for your project,

and then people can come in and help

 

[xqqxqq]

I have a SSL9K channel strip, I do not know how to give it power, I ask, SL911 What power?+18 -18-24 +48 ？how to connect to the pin?
SL911 audio input and output to connect?
Thank you!

Hi,
you should start your own thread about this.

publish some pics of the strip and connectors

getting the schematics would be the first step for your project,

and then people can come in and help

Thank you!

OK, I uploaded the pictures section channel.

 

[xqqxqq]

 

[Di_Sousa]

you should start your own thread about this. (publish the photos there)

getting the schematics would be the first step for your project!

 

[xqqxqq]

 

[bieckmusic]

Hi everyone,

I'm planning on building the power supply from the SSL9k.  I made a self-etch pcb of the power supply from the trace in the pdf attached on the first page.  I was wondering, does the image need to be reversed before printing onto the press and peel paper.  I think so, but am not sure.

any help would be awesome!!

thanks,
Greg