Voltage test

Hello all,

I started making my Shruthi tonight (!), midnight edition with SVF filter. I’ve reached the part with the voltage test, for the first reading I get 4.92 (good), for the second I get 4.88 not within the specified range of -4.9 to -5.1. Is it close enough? What could cause the slight discrepancy? It’s not an expensive multimeter.

Thanks!

Yes, close enough.

Random part variations + multimeter not super accurate.

Most probably the multimeter itself. Personally I think that being off by 2.4% is still good enough. That’s supposing the meter is accurate. No reason to worry just yet.

High fives!

The discrepancy may come with a not too good batch of 7805 and 7905. Happened to me, too…is not really an issue and still within tolerances.

Oh that reminds me of another question - do I need to clip the legs of 7805 and 7905 at the bottom of the board? I was hesitant to do this as I wasn’t sure if they were that long for a reason. I’m totally new to this.

Just stick the 7x05 regulators through the PCB holes as far as possible, solder them in place. Be careful not to mix them up, clip the legs when they’re soldered in place so that you end up with small volcano-looking hills of solder where the formerly long legs were.

You only need to watch leg length if you attach a heat sink, need to bend the legs etc.

Always cut after soldering stuff in place.

Thank you very much, I really appreciate it