so ive been putting this off for a while but i finally went ahead and did the extended TX mod on my IC-7300. not the mars/cap thing specifically, just wanted a bit more flexibility on the low end of 160 and also wanted to mess around with some stuff outside the normal ham bands for testing purposes. pretty straightforward honestly, just a couple jumpers on the board once you get the bottom cover off.

while i had it open i also went ahead and replaced the stock cooling fan since mine was starting to get a little rattly at high duty cycle. threw in a Noctua NF-A4 which required some minor bracket fiddling but its dead silent now and seems to move at least as much air. ran it for a couple hours on FT8 at 80-90w and the finals barely got warm compared to before.

the thing im still debating is the audio mod. ive seen people swap out the stock mic element for something with a flatter response and supposedly it makes a noticeable difference on SSB. has anyone actually done that and thought it was worth it versus just using an external mic? feel like at some point youre just adding complexity for marginal gains but curious what others have found.

did the fan swap on mine last year and yeah same deal, huge difference. i used a different fan, just a generic 40mm 5v unit from amazon that i found with decent reviews, and it works fine but i bet the Noctua is quieter. might be worth the few extra dollars.

on the mic element thing — i did try it, swapped in a Panasonic WM-61A capsule into the stock HM-219 body. takes about an hour if youre careful and you need to be comfortable with teeny tiny soldering. the result was noticeably better on the air, people were commenting without me even asking which is usually a good sign. that said i eventually moved to just using a Heil PR-781 on a boom and thats way better than either version of the stock mic so... yeah. if youre already thinking about an external mic id just do that instead of the element swap.

whats the point of the extended tx mod if youre licensed for all the normal bands already, genuinely curious not trying to start anything. is it just for the testing flexibility you mentioned or is there actually something useful outside the ham allocations that hams are doing these days