so ive been putting this off for like two years because i was nervous about voiding warranty and also just kind of intimidated by opening up the radio, but last weekend i finally did the MARS/CAP mod on my IC-7300 and honestly it was way less scary than i expected. just a couple of jumper pads on the board, takes maybe 20 minutes if youre not rushing.

the reason i finally pulled the trigger was i picked up a second 7300 for a good price at a hamfest so i figured if i bricked one it wouldnt be the end of the world. spoiler: i didnt brick anything. both radios came through fine.

now the thing is i dont actually do MARS or CAP work, i mainly wanted the extended TX range for some experimentation on the low end of 160 and also just to have the flexibility. the mod itself is well documented, there are a few youtube videos and the usual forum threads if you go looking. my only gripe is the reassembly — the ribbon cables on that radio are a little fiddly and i slightly bent one of the connectors but it seated fine in the end.

has anyone done any other mods on the 7300 worth talking about? ive seen some people mention the cooling fan replacement because apparently the stock fan can get noisy over time. mine isnt bad yet but im curious if thats actually worth doing preemptively or just wait til it becomes a problem.

yeah the fan thing is real, mine started getting audible around the 3 year mark. i swapped it out for a noctua 40mm and its basically silent now. you do have to do a little adapter work because the connector isnt the same and the voltage curve is slightly different but nothing crazy. theres a thread on eham somewhere with the exact part numbers. the hardest part honestly was just getting the case back together without scratching anything, i always seem to do that.

also on the MARS mod — totally agree its less scary than it looks. i did mine about 18 months ago. just make sure youre doing the right revision of the mod for your serial number range because there were a couple different board layouts and the pad locations moved. the older threads dont always make that clear and i had a moment of confusion before i found the right documentation.

the cooling mod is worth it imo but only if your shack runs warm or you do long digital sessions. i run JS8Call and FT8 a lot and my 7300 was getting pretty warm to the touch during summer. swapped the fan and also added a small external fan blowing across the back of the chassis and temps dropped noticeably. probably overkill but whatever it makes me feel better.

one thing i'll throw out there — if you haven't already, look into the SDR panadapter tap some people do with the 7300. i know it already has a built in waterfall but i saw someone tap the IF output and feed it into an external SDR for a wider view and it looked really useful for contesting. havent done it myself but its on my list