ok so i just upgraded from tech to general last month and im trying to figure out where i can actually transmit on 40 meters. i looked up the FCC part 97 allocations and also found the ARRL band plan and they dont seem to match up exactly and now im more confused than before i started looking.

like the FCC says generals get phone privileges starting at 7.175 but then i see people talking about the gentlemans agreement and staying away from the dx window around 7.175-7.200 and some guys on the local repeater were saying something about band edges being dangerous and you should never operate right at the edge. is that a real thing or are they just being overly cautious? i dont want to accidentally transmit somewhere im not supposed to or step on a dx pileup or whatever

also what does LSB vs USB matter here, does the 7.175 start point mean the carrier frequency or the edge of the actual signal because i feel like that could matter

yeah this trips up a lot of new generals, dont feel bad. the FCC allocations are the legal limits, so for you on 40m phone it really is 7.175 to 7.300 MHz. but the ARRL band plan is more like a community agreement on top of that, trying to keep things organized so dx stations and domestic ragchewers arent constantly walking on each other.

the band edge thing is legit advice though. when you're on LSB, your carrier is at say 7.175 but the actual audio sidebands extend downward from there, so if your voice peaks are going out to maybe 3khz of bandwidth you're technically putting signal below your lower limit. most rigs have some drift too depending on temperature and how old the radio is. so the old timers saying stay a few khz inside the edge arent wrong, its just practical. 7.178 or so gives you some breathing room without worrying about it.

as for the dx window thing around the top of the general segment, thats just courtesy really. you wont get arrested for using 7.290 but you might get a earful from someone

went through the exact same thing when i upgraded. honestly what helped me was just listening for a few weeks before i ever transmitted on hf. you start to get a feel for where the dx pileups are and where the regular rag chew nets hang out. no chart really prepares you for just hearing how the band actually gets used day to day.

one thing i'll add is the 7.200 upper edge for generals used to cause a lot of drama back before the band plan got revised, there used to be a notorious net that would park right there specifically to mess with people, look up 7.200 if you want a rabbit hole. anyway point being band edges attract weirdos sometimes so just worth knowing about