broadband ut300 modem,link light stays on forever and had to restart to get connected

  • Thread starter Thread starter MEGAN
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after learning few from vids and reading , the previous day to the modem got irreversible symptoms was a lightening thunder rain night. my assumptions is it messed up the ethernet port or isolation transformer or adsl phone line chips may be. any one can give me few ideas about to protect modem , really it was just modem this time, it wasnt my computer ,but in future i dont want to take risks. gota protect these lines travelling to my mobo and destroying everything in its way. or i should simply take off adsl phone line off when i am not using it. and computers ethernet lan too.??
 
APC's computer UPSes used to come with a phone-line and RJ45 ports which were supposed to offer surge protection. Not sure if their new ones have it or not. Googling for "phone line surge protection" or "RJ45 surge protection" shows some devices available from US but I don't think they are available locally.

I've seen 2 instances of blown ports - both with the local broadband providers and both possibly due to the providers' lines shorting with power cables from falling branches or something like that. In both, only the specific lan port, into which the incoming line was connected, was blown. Other ports were working correctly with no damage to devices connected through them.
 
oh thats good to hear , just the port goes bad but leaving connected computer fine. thats a relief to hear. i was getting paranoid for my computer parts blown off. there are diy surge protectors for extension boxes but have not come across for rj11 phone lines. actually this comes under responsibility(major part) of isp provider to safe guard their lines well ,wish my modem had 2 lan ports hehe , but anyway the dsl line light always solid (no flickr) no matter what, today i even heat gunned the broadcom chips with flux for about 30-40 secs , ( source internet vid saying when all lights are on ,may be some chip got desoldered ) but it was the same result as before , putting the power - power ,dsl light ,keeps lit - no change with input of phone line , then lan light pc/usb will on off on off cycle when lan is put, in computer i can see its trying to connect modem ,and its forever. if i try with usb , the red light instead of green light (lan light) but it keeps lit as before when normal. remote usb ndis doesnt come as before . so usb line gone too i guess.
all these years for about a decade this is the first time i came across this problem lightening adsl and modem boom ! i am surprised shocked seeing so many of them had thier computers blown off , even with monitors ! this is scary. we dont even have black friday sales as they have lol to get cheaper electronics .
 
by the way when i examined the board little much closer today, i think i found few capacitors blown off ! in front of isolation transformer c34 c35 c133 c19 , when i shorted 34 35 133, the board switches off ,but not when c19 . but i am unsure if the capacitors are left unjoint purposefully or it was blown due to some power problems. mm and i looked in the pics of your last post.it had the capacitors empty too in front of lan transformer. so just the usb cable is enough to see whats going on inside this modem ? wish it had little more lesser price tho. thanks for keepin on this discussion :) i have ch341a eeprom ,could be this any use here ?


also this is the chip 25X16VSIG - i read the voltages ,vcc shows 3.7 v as per data sheet . i desoldered the chip and kept it in my ch341a usb flash programer. it detects the chip and even read the whole bios in the chip.. now i guess i have to try flash ut300 to it ,but i am in dilemma now. been searching for ut300 firmware bin file for a while now. not getting it anywhwere, but made a back up of my present flash bin from this chip.
 
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can you give me your adsl modem firmware.. but i only have this ch341a ,it has open file types as bin, eep,hex . i flashed the bin file from that russian website.. but no change,its the same result. i am not sure what file format it should be to flash this chip in modem.
 
oh ok, i tried to read the board with ch41a programmer through serial port in putty, but it was all gibberish , i tried ,ubt i think it might be due to not doing through jumper cables too. may be i will buy it later and try it all again.. or will just throw away this board to scrap . from another forum one person said it might be due to cpu oscillator , may be i will try changing it too.
 
Oh I didn't know ch341a programmers could be used as serial readers. Assuming everything else went right, perhaps rx tx pins on the serial port were misidentified? You could switch and try.
 
yes it was all garbled grey boxes coming in putty ,got to know that its because of bad jumper cables, i have to buy it, i dont have any, i tried soldering the jumper wires, but its not joining ,i am afraid not to heat the usb too much . can you tell me if the oscillator is bad,how much hertz i should buy for the modem ? actually how to even check if its gone bad
 
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