I wanted to solder an ON/OFF switch for my arduino. So I bought some switches: HERE (https://www.amazon.de/gp/product/B071X935QN/ref=ppx_od_dt_b_asin_title_s01?ie=UTF8&psc=1)
It works, but there seems to be some power drop since the lcd display which I connected to my arduino will no longer work properly (but connecting it to the battery directly without my soldered switch works). See attached image of my soldered switch.
I assume the poorly made connections between cable and switch is causing this.
Are there some kind of adapters which I can use to connect pin cables with power jacks/switches etc?