so i've been lurking on this forum for a while and finally pulled the trigger on a QFX... wait no, a QCX Mini from QRP Labs. built it over like three evenings, which honestly took longer than i expected because i kept second-guessing my solder joints and checking everything twice. maybe four evenings if i'm being honest.

anyway took it out saturday to a nearby hilltop with a random wire antenna i threw together out of some 28 gauge hookup wire i had lying around - probably not ideal but it was what i had. ran it off a little 3ah LiFePO4 pack and honestly could not believe i was making contacts. worked a station in ohio from upstate NY on 40m with maybe 4 watts and he came back first call. i know that's not rare for QRP but when you're sitting on a hill in the wind with a tiny box you built yourself it feels pretty wild.

my question is mostly about efficiency stuff going forward. the rig gets a little warm and i'm wondering if that's normal or if i should be looking at how i'm loading the antenna. also curious if people have recommendations for a better portable antenna - the random wire worked but SWR was all over the place and i had to really crank the internal tuner. does the qcx even have a tuner? i think it doesn't and maybe i'm thinking of a different rig. anyway any thoughts welcome, just wanted to share the experience too

congrats on the first QRP contact, that ohio QSO sounds like a great way to get started. to answer your tuner question - no the QCX Mini doesn't have a built in ATU, so if you were getting it to match with a random wire you were probably just getting lucky with the antenna length resonating close enough on that band, or the rig was just working into a bad match and coping. running into a high SWR will definitely cause it to run hotter than normal since the finals are working harder than they should be. not gonna kill it right away but worth sorting out.

for portable antennas i'd really suggest looking at either a EFHW (end fed half wave) with a small matching transformer you can wind yourself, or just a simple dipole cut for whatever band you're mostly gonna be on. the EFHW is nice because it only needs one feedpoint and you can throw it up in a tree pretty quick. there are kits for the matching unit too if you dont want to wind your own toroid. 40m is a great band for QRP by the way, you picked a good one to start on.

yeah the warmth thing is usually the PA transistors doing their thing when the antenna match isnt great. ive had mine get pretty toasty too when i was testing into a dummy load that wasnt quite right. just make sure theres some airflow and you should be fine for normal operating sessions.

also just wanted to say the 28 gauge wire thing made me laugh a bit - not in a bad way, ive done worse. i once used speaker wire as a dipole at a campsite because i forgot my antenna at home. worked fine on 20m. QRP is kind of forgiving if the band is cooperating. welcome to the rabbit hole by the way, once you start building kits it kind of doesnt stop