Troubles with the Power Supply

Hello there community,

I´ve recently bought a Shruthi-1 DIY-Kit and soldered everything together (i´ve not used the assembly instructions since i´ve found them just after i´ve soldered everything). So there were two little mistakes i´ve figured out after checking if everythings ok. The first was that i´ve soldered the 10pF condensor into the false place so i desoldered it and it broke, i went to my local electronics dealer and they only had a 12pF condenser. So my first question is: Is it fine to use the 12pF since they are manufactured with some tolerance etc.? The second issue was that i´ve accidentally switched the LT1054IP and TL072CP. I connected them to a 9V 600mA power with the +Pin inside and measured the voltages at the pins shown in the assembly manual. Since the voltages were 1,5 V at the red marked and around 0 V at the green marked i´ve checked the orientation of the ICs and found out they were switched so i switched them back and checked the voltages again. This time they were even lower (about 1 V and again 0 V). Also the marked Pins at the two LM13700N weren´t at the 1,5 V but they should have been or is this because i fucked up the two ICs at first? My second main question is: Do i have to buy a new LT1054IP and TL072CP or is there another way to get this fixed or how can i check if the two ICs are destroyed?

Thanks for taking your time to read this
Yours mnmldani

12pF is fine.

I suggest you to replace the LT1054 and the tantalum capacitor next to it.

Thanks for the quick reply. I will do so and let you know if it worked

so i got the tantulum capacitor, the TL1054 and the TL072CP replaced. But i figured out that the two regulators 7805 and 7905 also were misplaced so i swiched their positions and everything is working fine now
thanks for your help !

Easy mistake to make. I imagine that was the problem all along…


Where did you find the lt1054? Im having trouble replacing mine

Reichelt, Mouser, Farnell, Digi Key , take a look to the BOM . there is the order number .