Next, it was time to find a key. I prefer iambic keyers but the only one I own is chrome Bencher set of paddles. It's just too heavy for a backpack radio like the QCX-Mini. So, I cruised the web and found a nice design on Thingverse. I fired up my 3D printer and went to work. I used the "mini" version which is very small. After a couple of days of fiddling with the fine-tuning, the keyer seemed to work well. I used magnets instead of a metal spring and it has a fairly nice feel. I built a 40m End-Fed Half-Wave antenna and picked up a neat 3Ah 12V Lithium-Ion battery pack recommended by a guy on Reddit.