POwer test of 4Pole Mission

Good morning !

I think i have a problem on my shruti 4 PM filter board.
I have just finished solder, and at the red - blue- green point,
i have +3V and -3V everywhere

Have you got an idea ?

With a photo


Which power supply are you using? What is the voltage at the SW “bridge” near the power connector?

It’s a 9V power supply, and i have 5.80V at SW bridge.
POwer supply delivered 8.96V

I’m at work, i can’t response immediately.

Thx olivier for your help

Looks like your power supply is too weak - I think the 8.96V you have measured is without load, right? As soon as you connect it to a circuit, the voltage drops to 5.8V and this is not enough for the regulators. Try another one.

Yet it is the same that works with the smr4 mkII
I don’t understand.
I have a selector on the power supply, can i increase to 12V ?

Yes, 8.96V directly at the power supply

I have 8.94V between SW bridge point un ground point on the eight point connector

So at which point do you get 5.8V?

What are the voltages on the I / O / (-) pins of the 7805 and I / O / (+) pins of the 7905?


To imbed images use exclamation points around the hyperlink like ! http://… ! but omit the spaces.

I think you’re measuring the voltage at the two electrolytic capacitors in front of the voltage regulators…

Sorry i have 0V between this two point

Hmmm, this is not really what I asked…

What are the voltages on the I / O / (-) pins of the 7805 and I / O / (+) pins of the 7905?

it’s not these point ?

(I have a problem with image)

like this:


edit: not sure, if imageshack allowes to ebedd images this way.

Voltage regulator:

Yes titus, between - of IC11 and + of IC12 !and i have 0V
It’s not that ?

olaaa, it’s not the same

I think I’ve found. I reversed the two Voltage regulator.

I am awfully sorry My mistake is resolved.
I have +5V and -4.99V