I did an instrumentation amplifier on pcb, and I was enthusiastic in making lots of test points for troubleshooting. Now pcb is ready but lots of noise compared to my breadboard version!!. Do the test point pins act like antennas?

The pcb also repeats the same circuit a couple of times across one pcb because I want to make parallel measurements sometimes. So lots of signal pins that are sometimes not connected when I don't use all the circuits in the same board.

Is there a way to cover them pin headers so that it doesn't collect more noise?

Thankyou.

 

Many cooks spoil the soup!......... on a serious note, it could be due to an unclean PCB, clean it with a PCB cleaning spray....... then again, it could also be due to many component terminals soldered too close to each other for comfort resulting into circuit noise due to 'parasitic capacitance' between the terminals.

You can also go in for shielded test probes which reduces signal noise.

 

Everything is a guess without the schematic and the PCB layout.