noise floor looks about the same on the waterfall which is confusing me because if it was a preamp issue or front end damage i'd expect the noise floor to drop too, right? but signals that should be S7 or S8 are barely moving the meter. im starting to wonder if its the AGC doing something weird or maybe one of the IF stages. anyone had something similar with this radio or any icom in general? i really dont want to ship it off to icom if i can figure out what's going on first.

i bought it used about 8 months ago and its been perfect until now. no idea if it was dropped or anything before i got it. started noticing it when i was having trouble breaking a pileup on 40 and thought it was propagation but then i actually checked the power output and yeah, something is wrong.

anyone seen this on a 7300 before? im wondering if its a PA transistor issue or maybe something on the LPF board for that band. havent opened it up yet because honestly im a little nervous about voiding any warranty type stuff but i think im probably outside that window anyway. tempted to just send it to icom but the wait times i keep hearing about are rough.

already went through the obvious stuff - checked the coax from the rig to my meter (swapped cables to confirm), confirmed the wattmeter is accurate with my other radio, did a factory reset just to see. nothing changed. the radio sounds clean on receive, no weirdness there. transmit audio reports are fine from other stations.

i did notice the finals area gets a bit warmer than i'd expect but not crazy hot, and there's no fault indicator or anything popping up in the menu. starting to wonder if one of the PA transistors is partially gone or if theres something upstream limiting drive to the finals. anybody dealt with this before on a 7300 or similar SDR-based rig? not sure if i should crack it open and start probing or just send it to a service center.

ive already pulled the antenna connector off and tried a dummy load on the receive side just to rule out the obvious stuff. also checked that the preamp wasnt doing something weird, turned it off and on, changed settings back to factory, nothing. the RF gain is up, AF gain is up, its not muted. its genuinely just silent.

my first instinct is the front end got cooked somewhere between the antenna connector and the first IF stage but i really dont know where to start probing on this thing. anybody had a similar experience with these or know which part of the signal chain typically takes the hit in a near-strike situation? i have a service manual but the block diagram is only kinda helpful without knowing what im actually looking for.

already pulled it apart and swapped the PA board because that was the obvious suspect and honestly i had a spare from a parts unit anyway. no change at all. i scoped the ALC line and its not going crazy or anything, voltages on the driver stage look normal to my eye. the finals are running warm but not scary hot. im starting to wonder if its a thermal issue somewhere upstream of the PA or maybe something weird with the RF sensing circuit but im kind of grasping at straws at this point.

anybody dealt with this specific failure mode on one of these? the icom service manual is actually pretty decent but its not exactly chatty about intermittent stuff like this.

thing is it happened kind of gradually i think? like i noticed i wasnt getting the signal reports i used to and then actually put a wattmeter on it and yeah, way down from 100w. the finals maybe? i really dont want to ship it to icom because last time that took like 6 weeks and cost more than i expected. wondering if anyone has seen this before or has an idea where to even start poking around before i give up and send it in.

already checked the obvious stuff -- PA fuse is good, supply voltage is solid at 13.8, no ALC weirdness on the meter that i can see. the driver board is my next suspect but honestly i haven't cracked one of these open before and im a little nervous about getting into the PA section. anyone dealt with this specific fault on an 897? is there a known weak point i should be looking at first before i start probing around in there

anyway hooked it up to my dummy load and watt meter and yeah, its doing maybe 8-10 watts on a good day across all bands. drive level seems fine, ALC is behaving more or less how i'd expect, the display and everything else works fine. RX sounds great actually, really clean. so im pretty confident the problem is somewhere in the PA stage and not upstream of that.

opened it up and one of the 2SC2290 transistors looks a little sus to me, theres some discoloration on the case that i dont love the look of. havent pulled it yet to test it though. before i go yanking parts out i just wanted to see if anyone has been down this road with a 757 before, any gotchas i should know about? also wondering if its worth going with the stock transistors or if theres a better drop-in at this point since the originals are kind of a pain to source.

pulled the cover and did a visual, nothing obviously cooked. im thinking driver stage but honestly i dont have a ton of experience digging into these SDR rigs vs the older stuff where you could kinda trace signal path more intuitively. anyone gone into one of these for a similar symptom? wondering if its worth pulling the finals to check or start somewhere upstream first. i do have a scope and a decent RF probe if that helps narrow down where to look.

then i noticed it's worse when the shack computer is on but even with the computer completely off and unplugged it's still sitting there. the bands above 40m seem mostly fine, 20m maybe has a tiny bit more noise than usual but nothing dramatic. just 40 and 80 that are bad. i've done a factory reset twice, updated the firmware, tried a different antenna feedline, even borrowed a buddies dummy load to rule out the antenna entirely. noise is still there with the dummy load connected.

at this point im wondering if something inside the radio itself has gone south. maybe a filter cap somewhere or something in the front end? the radio is about 4 years old and has been running pretty much every day. any ideas before i ship it off to icom?

i pulled the top cover and poked around a bit but i dont really know what im looking for. i know these rigs have band-specific driver stages so im wondering if theres a transistor or something on the 40m path that's starting to go. the rig is maybe 8 years old, bought used, no idea what the previous owner did to it. anyone been down this road with an 857?

already reseated all the connectors i could find and reflowed a couple joints that looked sketchy on the PA board near the finals. no change. pulled the driver transistors and they test okay on the bench, or at least they arent shorted. not sure if im missing something obvious here. anybody been inside one of these for a similar issue? wondering if it's the pre-driver stage or something further back in the chain before it even gets to the finals.

my first guess was the PA transistors running hot but i pulled the top cover and stuck a thermal probe around and nothing is getting crazy hot, the finals look fine. someone on another forum suggested maybe the LPF relays but i havent gotten that far yet. i did recap a kenwood once but the 7300 feels way more involved to get into.

anyone dealt with this specifically on a 7300 or similar ICOM? wondering if this is a known thing before i start throwing parts at it.

pulled it apart last weekend and checked the obvious stuff — heatsink compound was basically dried out and crumbly which i replaced, cleaned out a pretty impressive amount of dust from around the PA area, checked that the fan was actually spinning freely and not just making noise. reseated everything. still doing it.

output power looks about right on my wattmeter so its not like the finals are gone, but something is definitely dumping more heat than it should. SWR on the antenna is fine, been using the same dipole for years. wondering if maybe one of the driver transistors is partially cooked and making the finals work harder? or maybe a bias issue? i have a service manual but my bench skills are decent not great, i can do component level stuff but i dont want to just start shotgunning parts at it

already pulled the finals and they tested bad so i replaced them with the recommended 2SK2975s, resoldered everything, checked the driver stage too and that all looks okay with the signal tracer. still nothing coming out the antenna port. the SWR/power meter i'm using is a pretty decent Bird so its not a meter problem. just wondering if anyone's been down this rabbit hole before because i'm running out of obvious stuff to check and the service manual is only so helpful past a certain point.

i already went through the obvious stuff, checked the antenna, tried a dummy load, reseated the connectors i could get to without fully disassembling it. swapped coax. still the same thing. its like the finals are just... unhappy on that specific band and i cant figure out why. has anyone seen this on a 7300 or had to dig into the PA board on one of these? im comfortable with SMD work but id rather not go poking around blind if someone has a schematic note or a known failure point on that board.

then last week it started doing this thing where on 40m specifically the display flickers when i transmit, which is just... a new one for me. never seen that before on any rig. receive still seems fine across all bands which is making me think the PA or driver stage took a hit from the drop rather than something in the frontend.

ive got a decent soldering station and a scope so im not completely helpless but i havent done serious rig surgery before, mostly just connector work and stuff like that. was wondering if anyone had seen similar symptoms or had a gut feeling about what component i should be looking at first before i go pulling boards out. dont want to make it worse obviously.

ive already checked the obvious stuff — power supply voltage is solid at 13.8v under load, coax and connectors look fine, tried a dummy load and same issue so its not the antenna. SWR is reading normal when i do have a signal going out. the radio doesnt get unusually hot or anything and there are no error codes showing up on the display.

im wondering if its a PA transistor starting to go or maybe something with the ALC circuit itself feeding back wrong. anybody dealt with this on the 7300 specifically? i dont really want to ship it to a service center if i can avoid it but im also not gonna dig into the finals without knowing what im looking at first.

the radio powers on fine, display looks normal, all the menus work, SWR meter responds, ALC moves around like it should. but zero RF out. im talking literally nothing on my dummy load with a power meter in line. TX light comes on when i key up, everything looks normal except no power coming out the antenna port.

ive got a decent scope and a DMM, comfortable doing component level repair if i can figure out what to chase. my first thought was the finals but the driver stage before it could also be cooked. anyone dealt with one of these after a nearby strike? wondering if there's a known weak point in the PA section or if i should be checking something obvious first that im missing.

first thing i did was check the SWR on the antenna side thinking maybe a connector was thermally cycling loose or something but thats all clean. reseated all the connectors i could get to on the PA board without fully stripping the rig down. didnt help. the dropout seems to happen faster if im doing digital modes vs SSB which makes me think its heat related but the fan ramps up like it should and the heatsink doesnt feel crazy hot when i pull the cover.

i havent scoped anything yet, mostly because im trying to figure out where to even start. has anyone seen this specific symptom on a 7300 or even a similar icom? wondering if its the finals starting to go or maybe a bias issue that drifts with temp. i do have a service manual PDF but honestly some of the alignment sections are a bit over my head without some guidance on what to actually look for first.

i already ran through the basic stuff, recalibrated power output through the menu, checked my feedline and dummy load, swapped antennas just to rule that out. issue follows the radio not the antenna so its definitely internal. been reading about PA transistor failures being band-specific but i dont know enough about the 7300 architecture to know if that even makes sense for this radio. anyone dealt with this before or have a schematic handy that shows how the PA stages are split by band?

if i shut it down for 10-15 minutes and let it cool off it comes back fine and the cycle starts again. ive had the lid off and nothing looks obviously fried, no bulging caps that i can see, and the finals look okay visually. my first thought was a bad solder joint somewhere that opens up when the board expands from heat but i havent been able to find anything with a cold spray yet. anybody dealt with something like this on a 7300 or similar icom? im wondering if its worth sending to icom or if this is something a reasonably competent home tech could track down

i already went through the menu and reset the AF filter settings back to default because i thought maybe i accidentally bumped something. didnt help. tried different headphones and the internal speaker, same thing on both. swapped out the USB cable too just in case something weird was going on there even though i dont think thats related.

the radio is about 4 years old and has never been opened. no physical damage that i know of. just kind of gradually got worse over a few weeks rather than being a sudden thing. anyone dealt with something like this before?