so we have a county-level ARES exercise coming up in about three weeks and im trying to nail down the power situation for our comm station. last time we ran this thing somebody brought a cheap harbor freight generator and it was putting out enough noise to basically kill our HF capability for most of the morning. we ended up just running off a single 100ah AGM which was fine for the first couple hours but by hour four we were watching the voltage like hawks and cutting back on transmit duty cycle.

this time around i want to do it right. the plan is to run an IC-7300 for HF and maybe a dedicated VHF/UHF rig for local nets, probably a spare 857 or something. thinking about bringing my Honda EU2200i which ive used before and its been pretty clean, ran it through a scope once and it was way better than the HF gen we had last time. but im also wondering if its worth just going full battery this time with a decent LiFePO4 setup and a solar panel or two to top it off since the exercise is only 8 hours.

antenna side of things we're probably doing a resonant end-fed for 40/80 since we need to hit the state EOC, and a jpole or yagi for the VHF stuff depending on where we end up positioning. the site has some decent tree coverage so getting wire up shouldnt be a huge problem.

anyone done the math on LiFePO4 capacity for a full day exercise vs just biting the bullet and running the Honda? feels like a wash cost-wise once you factor in gas but the noise floor difference is probably real.

the Honda EU2200i is genuinely clean, ive run mine alongside a KX3 on 40m with no issues. the inverter generators are a totally different animal from the conventional ones. that said for an 8 hour exercise with an IC-7300 youre probably looking at somewhere around 20-25ah if your duty cycle isnt crazy, maybe more if you're running digital or doing a lot of back to back traffic. a 100ah LiFePO4 gives you real headroom and you dont have to worry about the voltage sag you get with AGMs once they start dropping below 50%. i run a pair of 50ah battleborns in parallel for field stuff and havent touched a generator in two years for exercises.

solar is nice in theory but honestly for 8 hours i wouldnt count on it as anything more than a supplement unless you can guarantee good sun angle and positioning. too many variables at a random exercise site. id say bring the battery as primary and keep the Honda as backup staged but not running, that way you have the quiet and the fallback if something goes sideways.

yeah the noise thing is real, we had almost the exact same problem at a SET two years ago. someone ran a conventional gen about 30 feet from the antenna feedpoint and S7 noise across basically the whole HF band. ruined most of the morning session.

one thing worth doing if you go the generator route regardless of which one - run the coax shield and your station ground to an earth stake and keep the gen as far from the antenna as the extension cord will allow. sometimes its not just RF coming down the power line but also noise coupling into the antenna structure if everything is bunched up together. learned that one the hard way. also ferrite chokes on the power lead going into the radio helped us knock a few S units off the noise floor at a later exercise.

for the end fed on 40/80 - what are you using for the matchbox? some of the cheaper EFHW transformers are lossy enough to matter on 80 especially if you're trying to push any kind of real power. just something to check before the exercise not during it