so we've got a county-wide ARES exercise coming up in about 5 weeks and i'm trying to figure out the best way to handle power for our main HF station at the EOC staging area. we're basically going to be running an IC-7300 plus a laptop for logging and maybe a second VHF/UHF radio for local tactical stuff. probably 8-10 hours of operation, not continuous TX obviously but we do get into some pretty sustained nets during these things.

my question is really about whether to bring a generator or just go heavy on battery. i've got a 30ah lithium pack and i can borrow another one that's similar so maybe 60ah total. at 100w output on HF the 7300 pulls like 20-22 amps transmitting and maybe 2-3 amps on receive so if we're doing a typical 20-25% duty cycle over the day it might work out. but then the laptop adds another couple amps and honestly these exercises always run longer than planned.

the other option is our club has a Honda EU2200i that's whisper quiet and would handle everything no problem. but dragging a generator to an EOC parking lot feels a little overkill and we'd need fuel, exhaust considerations, all that. i know some guys just run inverter gens for exactly this reason but i dunno.

also separately — anyone have thoughts on portable HF antennas for this kind of setup? we'll probably have a few hours to get set up before the exercise starts. i was thinking either a simple EFHW for 40/80 or maybe just throwing up a dipole. space isn't super constrained, it's a big parking area with some trees around the perimeter.

for that kind of runtime and load honestly just bring the generator. i know it seems like overkill but ive done the math on lithium packs for all-day ops more times than i can count and you almost always end up scrambling by hour 6. 60ah sounds like a lot until the duty cycle creeps up during a busy net or someone decides to run more gear than planned. the EU2200i is a great choice too, those things are dead quiet and the THD is low enough that the 7300 doesnt care at all — no weird noise issues like you sometimes get with cheaper inverter gens.

for the antenna i'd go EFHW if you have a decent 9:1 or 49:1 unun and a way to get the far end up in those trees. easier to deploy solo than a dipole usually, especially if you're also trying to set up the rest of the station. 40m half wave is around 66 feet so you've got options for angles depending on what trees are available. just watch your feedline routing near the generator if you go that route, keep some separation.

we ran almost the exact same scenario at our simulated emergency test back in the spring — 7300, couple laptops, a hotspot for the winlink stuff. ended up doing both actually, started on battery and had the generator staged as backup. worked pretty well mentally because you could see the battery state and decide when to fire up the gen before you got into trouble rather than scrambling.

one thing that bit us was the laptop charging situation. everybody forgets that when you've got a couple operators rotating in, laptops need charging and that load adds up. also had one guy show up with a big USB fan because it was hot and yeah that stuff just piles on.

on the antenna side, the parking lot with trees around the perimeter sounds like a good situation. if you can get one end of a dipole up 30-35 feet into a tree and slope it at an angle you'll do fine on 40. we used a 40/80 fan dipole at our last one and it was solid for both regional and some longer paths when 40 went long in the evening. bit more to set up but worth it if you have the time window you're describing.