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China fake parts 'used in US military equipment'

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Carbon_Rod

Thu May 24 2012, 04:17AM

Registered Member #65 Joined: Thu Feb 09 2006, 06:43AM
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Posts: 1155

@Sulaiman
Most knock offs are poor quality, but some items are recycled original parts from e-waste.

The industrial rules are to test items until failure, and compare variability of random samples.
This policy change was made in 1993 to reduce insurance premiums...

Automotive grade components have similar problems, but contain OEM parts.
... or plastic oozing yellow-brown Brominated flame retardant on "new" parts...

Conundrum

Thu May 24 2012, 06:53PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061

eeek!
I've heard that the quality of CFLs has dropped substantally because of the demand for cheaper bulbs.
In fact, some really really cheap ones use UV SMD LEDs inside the hollow tube to save on a gas fill, with a liquid inside to absorb the heat.

Neet Studio

Thu May 24 2012, 07:21PM

Registered Member #4037 Joined: Fri Jul 29 2011, 03:13PM
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Having the low pressure mercury vapor replaced by new technology because of cost pressure is an interesting development. This has the side effects of addressing the irony of supposedly "green" product that relies on a "toxic" component.

The liquid filled idea would help cooling. The higher volume in the liquid vs individual LED packages could allow for much more phosphor materials. This may be able to compensate for the drop in light output over lifetime (assuming that bad capacitors or other heat sensitive components don't fail first.)

They are exploring new ideas means at some point they are starting to innovate instead of simply doing copy cat. Japan back in the old days was going through the copy cat phrase before they started to innovate and surpass products that are invented by the west.

Conundrum

Thu May 24 2012, 07:59PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061

Yeah, I've often wondered why they don't do this in LCD monitors to allow higher brightness without a massive flat heatsink and fans.
Just dump all that heat into a flowing liquid then use a single passive heatsink at the side with a near silent piezo fan instead of the conventional noisy kind.
As far as moving the liquid goes, a simple inline pump using a ferrofluid seal would likely work fine.
The LEDs would likely outlast the monitor and be salvageable when it does finally break.

Neet Studio

Thu May 24 2012, 08:50PM

Registered Member #4037 Joined: Fri Jul 29 2011, 03:13PM
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A pump or liquid does not magically reduce the amount of heat having to be dissipated at steady state. It just let you transport that same amount of heat more efficiently without using a large cross sectional area to a more convenient location for dissipation.

Using a silent piezo fan means that you are trading off less air flow with less noise, you have to make up for that by using a higher surface area with a larger heatsink.

Steve Conner

Fri May 25 2012, 06:15AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

That can't be true. LED lamps are more expensive than CFLs already, before you add the labour costs of poking LEDs into a twirly glass tube.

Conundrum

Fri May 25 2012, 08:21AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061

I think they use something similar to those flexible strips used in laptop backlights.
Also, UV LEDs aren't *that* expensive, they can be less than 1p each in >100,000 quantities.

I'm sure I read somewhere about the LED CCFL, might have been "New Scientist".

Steve Conner

Fri May 25 2012, 09:10AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Nah, I don't buy it!

You have to compare the cost of a 10 watt bank of UV LEDs and the cooling liquid, with the cost of 5 milligrams of mercury and two filaments.

LED bulbs are certainly available, but they're marketed as LED and cost more than CCFLs.

Experimentonomen

Fri May 25 2012, 10:54AM

Registered Member #941 Joined: Sun Aug 05 2007, 10:09AM
Location: in a swedish junk pile
Posts: 497

I'm afraid china fake parts is the future of the electronics industry. The manufacturers of the genuine stuff cant get their products sold and are forced to shut down because everyone just go for the cheaper china parts in order to save a few cents.

Its a vicious circle. :(

Conundrum

Sat May 26 2012, 09:06AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061

Yeah, this is the problem with a failing economy.
The problem is that when the consumer has no choice but to buy the cheaply made goods because the expensive ones are double the price, it makes things worse.

Case in point, I just fixed a pair of Â£70 headphones where the connector was soldered using very badly made RoHS compliant solder, where every pin had detached.
Same with this printer, the solder joints just sheared off leaving dry joints underneath.
For once, solder paste is MUCH more useful than regular solder for this application as it can be deposited under the broken pins and correctly reflowed.

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