Welcome to my DIY audio forum.

Per-Anders Sjöström

Main Menu

Help with -5vdc for JSR-01

Started by chilli6565, July 19, 2011, 06:13:34 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.


I have already built the +5vdc version of the JSR-01 reg...but I am having trouble building a -5vdc version.
I have completed it but now get -7.6vdc on the output....I have done the following

input is -22vdc

H1 lamp is on

R10 = 47 ohms
C10 = 100 nF
C11 = Tin jumper

all above are done and ok

r4 wire bridge changed to r5 for neg version

6v8 zener in z2 position

t1 t2 and t3 are correct neg regs

tl431aid is in position ic8

any ideas??

pictures to follow 



DZ2 should be a LED. Use the same passive parts as for the +5v. When you have changed the DZ2, can you measure all voltages around the opamp? 2.5 V is a good start for pin 2 and 3 on the opamp. The voltages at the pins should be identical within a few millivolts.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff


Not sure I the +5v version I used the 6v8 zener in pos z2 and it works fine, but will change it here to a led and take measurements around op-amp  :-D


It seems that I may have forgot some details. This design didn't use a LED in this position. The zener should work in forward, meaning plus at the anode. Can you measure the voltages around the opamp?
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff