so ive had my FT-857D for about 4 years now and just kind of ran it stock the whole time. last month i finally dove in and did the mars/cap mod to open up the tx range, added the collins filter for SSB (the 2.3kHz one), and flashed it with the latest firmware which honestly i should have done like 2 years ago.

the collins filter made a bigger difference than i expected on SSB receive, voices just sound cleaner and thats not placebo i actually ran some a/b tests with a friend on the other end. the tx range thing is kind of whatever, not like i needed it but it was easy enough while i was in there.

anyway my question is more about the internal speaker mod some guys do - theres a thread on eham from like 2012 that talks about adding a better speaker element but i cant tell if the thread is talking about the same revision of the board i have. anyone done this recently or know if its still applicable to the later production units?

yeah the collins filter is legit, i did the same thing on mine and its night and day on crowded 40m SSB. the internal speaker mod though i honestly just gave up on because the chassis is so cramped in there and i didnt trust myself not to crack one of the ribbon connectors. ended up just running it into a small external speaker most of the time anyway which probably sounds way better than anything you could cram in that housing.

the eham thread youre talking about - is it the one by W5something? i vaguely remember reading it and thinking the mod made sense in theory but the measurements he posted were kind of hand-wavy. if you can find the part number he used you could at least see if the dimensions still match your board revision. Yaesu changed a few things around 2016 or so from what i remember reading somewhere.

done the mars/cap on three different 857s over the years, pretty straightforward. never bothered with the speaker thing tbh the audio out of that radio was always good enough for me running it mobile. if you want better rx audio just throw a little audioroot or even a cheap computer speaker on the ext jack and call it done, way less risk than cracking it open again.