Whatever you do, don’t touch the capacitors, especially if it’s an old TV, even if it’s unplugged. Could kill you. Old TV caps pack a serious punch (even when unplugged)
TVs that old didn't need to be hacked.
Ask HN: Tips for hacking a TV?
31–40 of 75 posts
Re: Ask HN: Tips for hacking a TV?
#32Whatever you do, don’t touch the capacitors, especially if it’s an old TV, even if it’s unplugged. Could kill you. Old TV caps pack a serious punch (even when unplugged)
The UN24H4500 is an LED monitor. The big risk in old TVs was the enormous voltages in the CRTs (which acted as a capacitor and stored energy even when off, and even pick up energy from background sources)
Aren't a lot of old TVs 'live chassis' as well as using very high voltages?
Re: Ask HN: Tips for hacking a TV?
#33Earlier quoted context omitted.
Mains will still kill you, even if its not 3.3kv or what was needed to run a CRT. Its always best to work out where the mains PSU is, and either cover/isolate it so that you don't touch it by accident. Even if turned off, there is a non-insigificant risk that there is either mains power lying around or some other large charge/current ready to bite. THe back of the inlet is also tends to be a hazard, so be really care…
Can't echo this enough. If you're working on anything that has been connected to residential mains... use a multimeter. They're cheap! Check the power supply for residual voltage from PSU caps. Discharge them safely before working on the equipment!
How do you discharge them safely?
Re: Ask HN: Tips for hacking a TV?
#34Not an answer but a follow-up question: is there open firmware for TVs like Openwrt for routers? I have never heard of such a project, but it sounds like it would be useful.
Re: Ask HN: Tips for hacking a TV?
#35Hacking TVs was a favourite pasttime of mine. There's nothing quite like flashing a TV with AOSP such that it thinks it's 55" smartphone. Lock screen and all. See if you can find a service manual for your TV. You'll want to get UART as soon as possible. Just remember crashes are for chumps: https://gist.github.com/Benjamin-Dobell/bb13f6169aaa48625453... PS. I think that may be my favourite piece of code I've ever wri…
I have a Samsung smart tv which I’ve never accepted t&c and never connected to wifi. I’d love to make it dumb or at least get rid of the nags to accept t&c or connect when someone accidentally hits the wrong button on the remote. Anything out there to do that?
Same. I'd be happy to turn it on and not have a menu over half the screen every time.
Re: Ask HN: Tips for hacking a TV?
#36Not an answer but a follow-up question: is there open firmware for TVs like Openwrt for routers? I have never heard of such a project, but it sounds like it would be useful.
Yes. I’d love this.
The software on tvs is awful. Plus many new tvs have ads baked in.
An open source OS would be a dream.
Re: Ask HN: Tips for hacking a TV?
#37Not an answer but a follow-up question: is there open firmware for TVs like Openwrt for routers? I have never heard of such a project, but it sounds like it would be useful.
There is this:
Re: Ask HN: Tips for hacking a TV?
#38Earlier quoted context omitted.
Can't echo this enough. If you're working on anything that has been connected to residential mains... use a multimeter. They're cheap! Check the power supply for residual voltage from PSU caps. Discharge them safely before working on the equipment!
How do you discharge them safely?
The correct answer is "bleeder resistor."
The other answer is "pliers."
(Make a connection across the terminals that have a voltage difference)
Re: Ask HN: Tips for hacking a TV?
#39Whatever you do, don’t touch the capacitors, especially if it’s an old TV, even if it’s unplugged. Could kill you. Old TV caps pack a serious punch (even when unplugged)
I think that's no longer true for modern flatscreen TVs. Older CRT TVs had caps charged to a dangerously high voltage, but all the caps on an LED/LCD TV should be a low enough voltage to be touch safe.
Some older flat panels use “cold-cathode fluorescent display backlights” and they’re driven by a high-voltage inverter, I believe - so it’s still a good idea to be wary.
Re: Ask HN: Tips for hacking a TV?
#40Not an answer but a follow-up question: is there open firmware for TVs like Openwrt for routers? I have never heard of such a project, but it sounds like it would be useful.