Reliability of LEDs: PF Members' Views and Experience

[sophiecentaur]

Instead of blaming spikes you should question the temperature of the semiconductors and the on/off switching transient. After being called on many occasions to hunt the source of “spikes on the supply”, I was always able to identify the real cause of the problem. It was never the mythical magical spikes that were the problem. Blaming spikes for the death of LEDs or MOVs is a bit like witch hunting. Spikes get the blame for much of the vandalism, but they are rarely given a fair trial before being found guilty.

The temperature factor may be (probably is) relevant to the short life. But that is no excuse and a half decent 'replacement' LED should survive in the conditions that its ancestors have tolerated for years.
You are right about the 'spike' monster but there are some badly behaved pieces of electrical equipment around in houses - despite modern manufacturing (and import) standards.

You're right, of course !
{ I gave up on electronics after my eyes became 'middle-aged' and solder went 'unleaded'... }

Would this help ? : http://spikehound.sourceforge.net/

Thanks for the idea. Yes, of course, there are dozens of digital oscilloscope modules which can be used with a laptop - I had just not thought along those lines. I might investigate the market. Up until now I have used an ageing analogue 'scope, which is very limiting in some respects.

 

[Nik_2213]

Went to fetch a 'frozen meal' out of *that* fridge-freezer, discovered top tray was seriously iced-up, whole needed defrosting the 'old fashioned' way...

While thaw was in progress, I took the opportunity to swap the 'standard' plug-top for one of the 'spike catchers' recently arrived from A*z*n. To my horror, I found the 'hot' lead's binding terminal's machine-screw was loose enough to wiggle. That can't have helped the noise-level on the power line !

I didn't swap the plug soon enough to determine if binding post had been 'running hot'. There was no obvious discolouration from arcing or scorching on post or hot-lead's 'bootlace' ferrule, but I only peered at them, did not use a hand-lens...

 

[jim hardy]

Yes, of course, there are dozens of digital oscilloscope modules which can be used with a laptop - I had just not thought along those lines.

Hmmm. I'm in the US. If somebody made one that put out NTSC video (analog television) it'd keep a lot of old TV's out of the landfills..
Did UK television go digital too ?

 

[Svein]

Hmmm. I'm in the US. If somebody made one that put out NTSC video (analog television) it'd keep a lot of old TV's out of the landfills..
Did UK television go digital too ?

I doubt you would be satisfied with the quality. NTSC resolution is 640x480 on a 4:3 TV. A cheap laptop has 1366x720...

 

[Guineafowl]

Did UK television go digital too ?

Yes, but you can buy digiboxes (digital -> PAL) and so still use your old CRT TV. We have a little old Trinitron still in service, although the colours are a little ‘off’ at times and it requires a manly thump to get them back again. When I get time, I’ll be looking for some advice on here on how to correct this properly and give the device a service, while there are still CRT people around who remember how to do such things...

 

[Baluncore]

When I get time, I’ll be looking for some advice on here on how to correct this properly and give the device a service, while there are still CRT people around who remember how to do such things...

The adice you will get is to recycle the old CRT, then use an ex-computer LED monitor with a second hand digital STB. You get a huge reduction in power consumption and a huge improvement in resolution.

 

[Guineafowl]

The adice you will get is to recycle the old CRT, then use an ex-computer LED monitor with a second hand digital STB. You get a huge reduction in power consumption and a huge improvement in resolution.

Yes, that sounds like the sensible solution. But I was thinking more in the spirit of keeping an old device alive.

 

[sophiecentaur]

Did UK television go digital too ?

Yes. Years ago. The terrestrial broadcast service was replaced over a fairly short time with FREEVIEW, which is free and replaced pretty much all conventional CTV services.
The switchover was helped a lot by a market flooded with flat screen sets. CRTs died very quickly. (No great loss except for a few lovers of old equipment. )

 

[Guineafowl]

Yes. Years ago. The terrestrial broadcast service was replaced over a fairly short time with FREEVIEW, which is free and replaced pretty much all conventional CTV services.
The switchover was helped a lot by a market flooded with flat screen sets. CRTs died very quickly. (No great loss except for a few lovers of old equipment. )

Er, yes - my love for old equipment is based largely on its repairability and build quality.

Example 1 - my mate’s newish Bosch dishwasher with a PCB fault that renders it uneconomical to repair, despite costing £300-odd. My old Candy unit is 30+ years old, is largely electromechanical, and still has parts available.

Example 2 - the Trinitron has outived a few flatscreens and then some. The chief advantage of the latter being that they take up less space in the skip/dumpster.

Example 3 - My parents have a microwave that is at least 40 years old, and has always been in daily use, in contrast to the crappy units I’ve thrown away after a few years.

 

[jim hardy]

I doubt you would be satisfied with the quality. NTSC resolution is 640x480 on a 4:3 TV. A cheap laptop has 1366x72

Oscilloscope display accuracy is a percent or three , CRT will do fine for that. Precision is in the numbers the computer writes on the screen.

Example 2 - the Trinitron has outived a few flatscreens and then some. The chief advantage of the latter being that they take up less space in the skip/dumpster.

I too have an old Trinitron, a 26 inch that's too heavy for me to move anymore. But it's convenient to the workbench..

Example 4 - the old Trinitron isn't "Smart" so it won't collude with the Russians to build a dossier on me.