so ive been sitting on doing the mars/cap mod on my IC-7300 for like six months now and finally just did it last weekend. wasnt as scary as i thought honestly, just moving a couple jumpers on the board after opening it up. now i can transmit outside the ham bands which i needed for some emcomm stuff we do locally on some NIFOG freqs.

but while i had the thing open i started wondering what else people do to these radios to squeeze more out of them. ive seen some stuff about the filter mods and tweaking the reference oscillator for better frequency accuracy but i dont really know where to start with that. anyone done the TCXO upgrade on one of these or is the stock oscillator already good enough that its not really worth the hassle. my main use is FT8 and some SSB DX so frequency accuracy actually matters to me more than it might for somebody just ragchewing on 40m.

also had a question about the speaker. the internal one is pretty mediocre, i know everybody says just use headphones but sometimes i want to just have it playing in the background. anyone swapped out the internal speaker for something better or is there not enough physical room to fit anything worth using in there

the TCXO thing on the 7300 is one of those debates that comes up every few months. short answer is the stock oscillator is actually pretty decent for most stuff, icom did a reasonable job there. but if youre doing FT8 seriously and you care about being dead on frequency then yeah the aftermarket TCXO mods some guys do can tighten it up. i think the stock spec is something like +-0.5ppm which sounds fine on paper but it does drift a bit with temperature, especially right after you turn the radio on and its warming up. give it 15-20 min and its usually settled.

i havent done the speaker swap myself but i did see somebody on one of the icom groups do it, they used a small tang band driver and said it helped a bit but the cabinet itself is the bigger limitation since its basically just a plastic box. you might get more mileage just running a small external speaker on the 3.5mm jack honestly.

did the same mod on mine about two years ago, went fine. one thing i'll say is double check your board revision before you go poking around because the jumper locations moved around a bit between production runs and some of the guides floating around online are for older boards. i followed one guide and spent a good 20 minutes confused before i realized the photos didnt match what i was looking at.

as far as other mods go the only other thing i did was add a small dc filtering cap near the power input because i was getting some noise on receive that turned out to be coming in through the power line from my shack setup. that cleared it right up. not really a performance upgrade more of a fix but it made a noticeable difference on 160 and 80 where i was getting a low hum on certain bands. probably a me problem not a radio problem but still.