ok so i passed my general a few weeks ago and im trying to figure out where i can actually transmit on 40 meters. i know there's a chart somewhere but every time i look at it i get confused because there's the FCC allocation and then theres also like a gentlemens agreement thing about where different modes go and they dont always line up

like i know phone starts at 7.175 for general class but then i see people talking about the dx window and staying away from 7.200 to 7.300 because thats where foreign broadcasters bleed in or something? and then someone at my club told me not to transmit below 7.125 even though technically i think i can? im just not sure what's a legal limit and what's just a convention people follow

also is the band edge thing a real concern like will i get in trouble for being too close to 7.175 or is that more of a just be careful situation

yeah the 40m situation is a bit of a mess to wrap your head around at first. so legally as a general you can do phone from 7.175 up to 7.300, thats your actual FCC allocation. everything below 7.175 is CW and digital for generals, techs dont get anything useful on 40 in terms of voice.

the dx window stuff around 7.200 is more of a voluntary thing — the idea being that DX stations and the people working them tend to congregate up there and if you just fire up a ragchew on 7.200 youre gonna step on a pileup and nobody will be happy. not illegal, just frowned upon pretty hard.

the band edge thing is real in a practical sense. your radio has to stay within its allocation so if you set your dial to exactly 7.175 and youre running USB, your actual transmitted signal extends upward from there so your suppressed carrier is at 7.175 but the audio content goes up a couple khz. you wont get in trouble per se but if youre transmitting LSB and dial down near 7.175 your signal could theoretically go below it. most people just stay a few khz inside the edge to be safe. 7.178 or so is a pretty common starting point if you dont want to stress about it

the band plan vs actual allocation thing tripped me up too when i got my general. what helped me was just remembering that the ARRL band plan is basically a suggestion that most people follow and the FCC part chart is the law. you only get in legal trouble for violating the FCC limits not for ignoring the gentlemens agreement stuff, though ignoring the conventions will definitely get you yelled at on the air lol

also worth knowing the 40m phone segment in the US is kind of squeezed compared to other parts of the world, ITU region 2 thing, so you'll hear a lot of foreign stations down around 7.100-7.175 where you cant transmit voice but can listen obviously