so we have a county-level ARES exercise coming up in about three weeks and im trying to figure out the best way to handle power for a sustained 12-hour deployment. the plan is to run a couple HF stations plus a VHF/UHF linked repeater node and maybe a winlink gateway if we can swing it.

my usual go-to has been a pair of 100ah LiFePO4 batteries with a 200w panel but honestly in late october around here the sun angle is garbage and cloud cover is pretty typical so im not confident ill get enough solar harvest to keep up with the draw. were probably looking at 30-40 amps average between everything running.

the EC wants to bring a small generator as backup but last time we did this someone ran a cheap harbor freight inverter gen and the RFI on 40m was absolutely brutal. like S7 hash across the whole band. so im thinking if we go generator route it needs to be either a honda eu2200 or the yamaha ef2000is, both of which ive heard are reasonably clean but I havent actually measured either on an HF receiver myself.

also still debating antennas. i was going to throw up an EFHW for 40/20 but our deployment site is a county fairground with not a lot of tall anchor points. maybe 25 feet max on a mast. anybody done a sloper or an NVIS configuration for field use and actually found it reliable for regional comms under 300 miles or so?

the honda eu2200 is noticeably cleaner than the HF units in my experience, ran mine next to an IC-7300 on 40m and the noise floor barely moved. that said i still run it through a cheap ferrite-loaded power strip and keep the generator at least 50 feet away from the antenna feedpoint, which helps a lot. bonding the frame with a ground rod also made a difference for me, picked that tip up from someone at a field day years ago and never went back to skipping it.

on the NVIS thing — yeah a low dipole at 25 feet on 40m is basically already NVIS whether you want it to be or not, so you might as well lean into it. for 300 mile regional coverage on 40m during the day thats actually pretty solid. at night youll want to think about skip but for daytime exercise comms it should work fine. i wouldnt bother with the EFHW transformer matching hassle at a site with limited height, just run a simple center-fed dipole and youll be fine.

yeah the generator RFI thing is a real problem and people underestimate it. we had a similar situation at our SET last year, somone brought a predator 2000 and we ended up just shutting it off and running battery only because the noise was so bad on the digital modes. winlink on Vara HF was basically unusable.

one thing we started doing is keeping a dedicated 50ah battery just for the SDR/monitoring station so even if everything else is running off generator that one stays isolated. probably overkill but it made the NCS happy. also meant we had a clean recieve reference to compare against when chasing interference sources.

for antennas at fairgrounds ive had decent luck with a linked dipole on a 33ft spiderpole, not super high but gets the job done for regional. the real pain is guying it at those sites, everything is asphalt or packed gravel and driving stakes is a nightmare so bring sandbags or water jugs as ballast.