QT428 System Initializing boots to nothing

I have a Q-see Qt428 it belongs to my brother. he reported that after a power surge it would not start up properly.

unit is 12 years old. I did some checking and found that every single capacitor on the board is bad. So I replaced them. same results won't fully start up.

tried a different power supply. same results. replaced HD no dice. after about 6 to 8 hours of searching the internet I stumbled on an ebay review that states the devices can be recovered by putting firmware on a USB stick and turning the unit on, the device would supposedly load the firmware. Problem is I don't have any firmware.

contacted the reviewer and had to play 20 questions, he pointed me at a supposed firmware file which when put on usb stick and placed in the unit, got accessed but did nothing more. I contacted "q-see" and have not yet heard back from them.

this device gave my googlefu a massive work out. I went on a wild goose chase for firmware (which ended up NOT being the problem).

Every single electrolytic capacitor in this device was bad, very high ESR to not even being seen by my capacitor testers. how it was working at all I do not know.



Replacing the capacitors did not change anything.

So in my searching I found little tidbits of information here, and there like:

this unit is the same as a TVT TD-2308SE which led me to TVT's site where I found GARBAGE instructions on how to access the linux OS on the unit through ye olde fashioned RS232 com port. the purpose of which was to upload firmware which their site had none of.

Now of course all my new computers don't have a COM ports so I had to dust off an old DELL laptop I keep for such instances. BUT the unit has a TTL com port and cannot directly interface with RS232. luckily I had a TTL to RS232 converter I got for another project.

of course there are no pinouts on the main board of this unit as to what is what. but I determined where +5v and ground were. 

 said a hail Mary and plugged it in. 

just friction fit and did not push it through all the way.

next I consulted the worthless TVT doc which had zero information on the what settings to use. It ended up being 115200bps n,8,1, software handshake.

as soon as I put that in to putty and connected I saw a prompt and something constantly repeating about there being no more space. I spent a good hour trying to follow the instructions to update the firmware with the supposed firmware that the ebay reviewer directed me to. It never worked.

after a crash course in linux commands (I'm a Windows and DOS guy) I went to plan B trying to fix the file system since it appeared the flash memory was full. I finally located a TMP folder and noticed a 490k file with a name (similar to) zxzycxwv or something like that (probably a random name). I deleted it, and the error message about no more space disappeared. I restarted the device and BOOM it started up normal and the only information lost was the time and date (dead CR2032) battery. 

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