so we have a county ARES exercise coming up and im basically being asked to run a standalone field station this time, no shack access, no shore power, nothing. which is fine i've done portable stuff before but always kind of winged it and this time the served agency actually wants us to document our setup and have it be somewhat repeatable so i need to actually think it through properly.

running an IC-7300 which i know isnt exactly the lightest field radio but its what i have and im comfortable with it. planning to run maybe 50-100w on HF, probably 40m and maybe some 80m in the evening if the exercise goes that long. for antenna ive been going back and forth between throwing up a end fed halfwave with a 9:1 unun versus just doing a simple dipole with a 4:1 balun. the EFHW is faster to deploy but ive had mixed results with it depending on the site and how much wire i can actually fit.

power is honestly the part im most unsure about. thinking about running a 100ah LiFePO4 battery with a small generator as backup, maybe a 2000w inverter unit. the 7300 pulls what, like 20-21 amps at full output? so realistically at 50w im probably looking at somewhere in the 10-12 amp range more or less. trying to figure out if i even need the genny or if the battery can carry me through a 6-8 hour op period without stressing it too much.

anyone done similar setups and have thoughts on the antenna choice or power math? also curious about grounding, last time i had some RF in the shack on 80m and im not sure if it was antenna or just the feedline being too close to everything

the power math is pretty straightforward if you work backwards from your duty cycle. at 50w out the 7300 is probably pulling around 10-11 amps at 13.8v but thats only when youre actually transmitting. for typical voice comms or even digital with some pauses youre probably averaging maybe 4-6 amps when you factor in receive current which is like 2 amps on that radio. over 8 hours thats maybe 35-50 amp hours depending on how active you are. a 100ah LiFePO4 will handle that without blinking, you wont even stress it to 50% discharge. id honestly leave the genny at home unless the exercise requires you to run higher power for extended periods or youre also running other gear off it like a laptop, radio, lighting, etc.

on the antenna question the EFHW can be great but youre right that its site dependent. if you have decent height and can get the wire up reasonably straight it usually outperforms a compromised dipole. but if youre in a parking lot or somewhere without good supports sometimes the dipole is just easier to control. one thing that helps with RF in the shack situation is making sure your counterpoise on the EFHW is actually doing something — a lot of people just let it dangle or dont bother at all and then wonder why they have common mode issues. also check your coax length, there are resonant lengths that can make things worse on certain bands.

yeah we ran basically this same kind of thing for a RACES drill last spring. ended up using an EFHW and it was honestly fine once we got it high enough — had a tree at maybe 25 feet at the far end and just did a sloper from the mast. 40m worked great, 80m was ehh but we made contacts. the genny thing is always the debate. we brought a Honda EU2200 mostly because the IC-7300 also had to share power with a laptop running Winlink and a small LED work light and it just made sense to not worry about it. if its only the radio you might be fine on battery alone like the other guy said.

one thing i'd add is bring way more coax then you think you need lol. every single exercise ive done someone ends up needing to reroute something or the feedpoint ends up in a weird spot and you wish you had another 20 feet of RG-8X sitting in the bag