JSR-03 and 05 problem (my first post in this Forum)

[pmantas]

heaveno all!
This is my first post in this forum. I need some help with JSR-03/05, I hope you can help me.

I have connected a JSR-03 and a 05 board to a regulated power supply in order to get +/-15V. The regulated power supply is already a +/-15V, but I want the final supply to be super-regulated.

The problem is:
When I connect JSR-03/05 to my +/-15 V supply what  I get at the +/- V outputs is about +/-12.56 V (not the wanted +/-15 V). At the LM117 and LM337 outputs I got +/-13.05 V.

For the components list I have used the same components suggested by Per-Anders and ... :
AD825
R12 not used
R11 used
R10 used
C9 not used
LED not used

What could it be the problem? Could you, please help me?

[peranders]

You must have 4-5 volts more in than you'll have out. 15 volts out => 19 volts in if you use a preregulator, otherwise 2-3 volts extra is needed.

[pmantas]

Per-Anders,
Thank you for the reply!
I think I'm going to take the +/- V directly from the pre-regulated part of the supply (+/-21V).
Just one thing more: Yesterday I connected a red led to the JSR-03 board, it lights on for a moment but, suddenly, it lights off. I tried with another led (this time a green one) and again the same.
What do you think could it be the problem?
Again, thanks a lot.

[peranders]

Did you draw the correct current through the LED or was it overloaded and died? Check if you have R13 10k, 1k or even 100 ohms!

Did you have any load?

[pmantas]

I think R13 is 10k
I didn't connect any load.
I don't have the board round here (I'm not at home). Next Friday I'll make some measurements and I'll tell you about.
Could it be that I need something more than 100R at R14?
Thank you.

[peranders]

You can do this basic troubleshooting:

Calculate all voltages and currents and assume the following:

Base-emitter 0.7 volts
LED 1.6 volts
Between pin 2 and 3 of the opamp +- 0 to 2 mV

Have you connected the SENSE inputs with a tin jumper on the solderside?

If you can take a close up photo it might help also. Max 200 kB filesize please, email me

[pmantas]

Ok Per-Anders!
As soon as I'll be home I'll e-mail and send the photo to you.
Thanks a lot

[peranders]

I'm glad that you have sorted out your problems (defect LED).

You have 14.67 V out and this is perfectly fine in most situations, no need for exacktly 15.000000 V. If you have a normal audio circuit, only low noise and a stable voltage is important. Congratulations!