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field comms setup for upcoming ARES activation - generator vs battery questions

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so we have a county-level activation drill coming up in about 3 weeks and im trying to nail down the power situation before we get out there. last time we ran everything off a honda eu2200i and it was fine but one of the other operators kept complaining about noise on 40m and i honestly couldnt tell if it was the genny or his radio or what. we never really figured it out.

this time around i want to try running the HF station off a lifepo4 pack instead, got a 100ah battleborn that i use for portable ops, and just keep the generator for the VHF/UHF stuff and the laptop. but im not sure if 100ah is going to cut it for a full 8 hour deployment if were running an ic-7300 at maybe 50-75w most of the time. i did some rough math and it seems like it should be okay but i never trust my own math on this stuff.

also the antenna situation — last drill we threw up a linked dipole on a 31ft jackite pole and it worked okay but takedown took forever when we had to move. anyone running something faster to deploy for HF field work? ive been eyeing those EFHW matchbox setups but not sure if the performance tradeoff is worth it for emergency use. want reliable not just convenient

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the noise issue with the eu2200i is almost definitely a grounding thing, those inverter gennys are usually pretty clean but if whoever set it up didnt bond the frame ground properly youll get all kinds of garbage on the lower bands. worth checking before you just abandon the generator for HF entirely. run a dedicated ground rod and bond the genny frame to it and youll probably be surprised how much cleaner it gets.

on the battery math — 100ah lifepo4 at the 7300s actual draw which is more like 20-22 amps at 100w output, call it maybe 15 at 50w, youre looking at somewhere around 6 hours of actual transmit time if you figure maybe 30-40% duty cycle on a voice net. probably fine for 8 hours honestly but id still keep the genny as a backup float charger option. dont paint yourself into a corner on a real deployment.

efhw matchboxes are fine, i use one regularly. not as flat as a dipole across the band but for emcomm you're usually working a pretty narrow chunk of 40 anyway so tune it once and leave it. 9:1 unun into about 67ft of wire gets you on 40 and you can squeeze 20 out of it too with the tuner. way faster to throw up than a linked dipole no question

we ran into the exact same genny noise thing at a SET two years ago. turned out it was a cheap extension cord acting like an antenna and coupling into the feedline. swapped it for a properly shielded cord and added a ferrite choke right at the radio end and it got way better. sometimes its not the generator at all its just everything being too close together with no attention to RF layout.

i'd also say dont underestimate how much the laptop alone will trash your noise floor if it's sitting on the same table as the radio running off the same power strip. seen that bite people more than once

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