We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

--
Rod

On Sunday, 10 July 2016 08:59:51 UTC+1, polygonum wrote:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

Can't you buy sackloads of these things locally?

https://www.youtube.com/watch?v=H_XiunR-cAQ

Just plug them into your old phone charger with the highest voltage. I have a shopping bag full of old chargers if you want to collect them.
PS:
Anyone know the best lamp-holders to go with them?

On Sunday, 10 July 2016 09:47:20 UTC+1, Weatherlawyer wrote:
On Sunday, 10 July 2016 08:59:51 UTC+1, polygonum wrote:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

Can't you buy sackloads of these things locally?

https://www.youtube.com/watch?v=H_XiunR-cAQ

Just plug them into your old phone charger with the highest voltage. I have a shopping bag full of old chargers if you want to collect them.
PS:
Anyone know the best lamp-holders to go with them?

OOPS don't watch the birdy:
https://www.youtube.com/watch?v=CIBIqaeiE2M

In article ,
polygonum writes:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

The G9 lamp format is simply too small for LEDs other than very low
power - there isn't enough surface area to dissipate much power and
remain within the working temperature of an LED. What's even worse
is G9 fittings usually restrict ventilation because the G9 halogens
have to run hotter than they do in free air to achieve full life.
I haven't looked for G9 LEDs, but I doubt anything more than 2W
would last long. If the G9 fitting has some ventilation restriction
which can be removed without reducing safety, then you should do
that when retro-fitting LEDs.

Steer clear of G9 fittings when buying lights - they're a technology
dead-end.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"polygonum" wrote in message
...
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles.

Since when have G9's ever fitted properly on the first attempt?

As for the LED verions of G9s I cannot recommend any. I have fitted a few
and I disliked them. A pack of 10 40W halogen G9s is about £7 at my
wholesalers and that is what I am sticking with for now.


--
Adam

On 10/07/16 08:59, polygonum wrote:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

None, other than "Caveat emptor". The G9s I bought on Amazon had nothing
like the lumen output stated. And when I bought some more (from the same
supplier as I wanted them to match), they were a slightly different colour!

It may be that you can get some with 400+ lumen output, but I would then
be very careful as to whether or not they would fit a standard G9
fitting. There are some reports that the brighter G9 LEDs are slightly
bigger than those with lower output - and those are already bigger than
G9 halogens.

--

Jeff

On 10/07/2016 10:33, Andrew Gabriel wrote:
In article ,
polygonum writes:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

The G9 lamp format is simply too small for LEDs other than very low
power - there isn't enough surface area to dissipate much power and
remain within the working temperature of an LED. What's even worse
is G9 fittings usually restrict ventilation because the G9 halogens
have to run hotter than they do in free air to achieve full life.
I haven't looked for G9 LEDs, but I doubt anything more than 2W
would last long. If the G9 fitting has some ventilation restriction
which can be removed without reducing safety, then you should do
that when retro-fitting LEDs.

Steer clear of G9 fittings when buying lights - they're a technology
dead-end.

Thanks - yes would avoid in future but they were already here.

They are actually lamps on ceiling fans so, although possible to change,
would be fairly expensive. Air flow is not a problem.

--
Rod

On 10/07/2016 10:40, ARW wrote:
"polygonum" wrote in message
...
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to
be easy to actually push into the receptacles.

Since when have G9's ever fitted properly on the first attempt?

As for the LED verions of G9s I cannot recommend any. I have fitted a
few and I disliked them. A pack of 10 40W halogen G9s is about £7 at my
wholesalers and that is what I am sticking with for now.


Oh dear... :-(

Thanks.

--
Rod

On 10/07/2016 08:59, polygonum wrote:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

Our "above bathroom mirror" lamp had been dead for about 18 months then
I finally decided to try an LED G9.

Went for the biggest one that would fit in the holder.

Can't comment on reliability as it's only been fitted for 8 weeks.
Other family members do have an annoying habit of putting the bathroom
light(s) on ALL the time regardless of whether it's required or not,
then they leave them on so it's getting quite a bit of use.

One I bought has a 5 year warranty so if I get 5 years out of my £4.99
I'll be a happy chap.

One I bought was this one
https://www.ledhut.co.uk/search/?q=4...+Capsule+Shape
in "Daylight" 4000K It's much brighter than the halogen it replaced
and the light is perfect for the bathroom.

Cheers
Pete


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On 11/07/2016 02:14, Pet @ www.gymratz.co.uk ;¬) wrote:
Our "above bathroom mirror" lamp had been dead for about 18 months then
I finally decided to try an LED G9.

Went for the biggest one that would fit in the holder.

Can't comment on reliability as it's only been fitted for 8 weeks.
Other family members do have an annoying habit of putting the bathroom
light(s) on ALL the time regardless of whether it's required or not,
then they leave them on so it's getting quite a bit of use.

One I bought has a 5 year warranty so if I get 5 years out of my £4.99
I'll be a happy chap.

One I bought was this one
https://www.ledhut.co.uk/search/?q=4...+Capsule+Shape
in "Daylight" 4000K It's much brighter than the halogen it replaced
and the light is perfect for the bathroom.

Thanks Pete - expensive!

--
Rod

On Sunday, 10 July 2016 10:33:46 UTC+1, Andrew Gabriel wrote:

Steer clear of G9 fittings when buying lights - they're a technology
dead-end.

How do you work that out? They look ideal for kitting out an old fridge for seeds.

On 11/07/2016 07:32, polygonum wrote:

One I bought was this one
https://www.ledhut.co.uk/search/?q=4...+Capsule+Shape
in "Daylight" 4000K It's much brighter than the halogen it replaced
and the light is perfect for the bathroom.

Thanks Pete - expensive!

Indeed. But if it lasts 5 years (with warranty replacement) then £1 a
year to stop the nagging is more than worth it.






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On Sunday, 10 July 2016 12:42:31 UTC+1, polygonum wrote:
On 10/07/2016 10:33, Andrew Gabriel wrote:
In article ,
polygonum writes:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

The G9 lamp format is simply too small for LEDs other than very low
power - there isn't enough surface area to dissipate much power and
remain within the working temperature of an LED. What's even worse
is G9 fittings usually restrict ventilation because the G9 halogens
have to run hotter than they do in free air to achieve full life.
I haven't looked for G9 LEDs, but I doubt anything more than 2W
would last long. If the G9 fitting has some ventilation restriction
which can be removed without reducing safety, then you should do
that when retro-fitting LEDs.

Steer clear of G9 fittings when buying lights - they're a technology
dead-end.

Thanks - yes would avoid in future but they were already here.

They are actually lamps on ceiling fans so, although possible to change,
would be fairly expensive. Air flow is not a problem.

https://www.youtube.com/watch?v=ol-lJ3NDY7A

https://www.youtube.com/watch?v=vbt2ojkXPuo

On Monday, 11 July 2016 10:13:45 UTC+1, Weatherlawyer wrote:
On Sunday, 10 July 2016 12:42:31 UTC+1, polygonum wrote:
On 10/07/2016 10:33, Andrew Gabriel wrote:
In article ,
polygonum writes:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

The G9 lamp format is simply too small for LEDs other than very low
power - there isn't enough surface area to dissipate much power and
remain within the working temperature of an LED. What's even worse
is G9 fittings usually restrict ventilation because the G9 halogens
have to run hotter than they do in free air to achieve full life.
I haven't looked for G9 LEDs, but I doubt anything more than 2W
would last long. If the G9 fitting has some ventilation restriction
which can be removed without reducing safety, then you should do
that when retro-fitting LEDs.

Steer clear of G9 fittings when buying lights - they're a technology
dead-end.

Thanks - yes would avoid in future but they were already here.

They are actually lamps on ceiling fans so, although possible to change,
would be fairly expensive. Air flow is not a problem.

https://www.youtube.com/watch?v=ol-lJ3NDY7A

https://www.youtube.com/watch?v=vbt2ojkXPuo

https://www.youtube.com/watch?v=hliHBeC1sco

On 11/07/2016 12:49, Weatherlawyer wrote:
On Monday, 11 July 2016 10:13:45 UTC+1, Weatherlawyer wrote:
On Sunday, 10 July 2016 12:42:31 UTC+1, polygonum wrote:
On 10/07/2016 10:33, Andrew Gabriel wrote:
In article ,
polygonum writes:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to be
easy to actually push into the receptacles. Also, want to have them in
about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

The G9 lamp format is simply too small for LEDs other than very low
power - there isn't enough surface area to dissipate much power and
remain within the working temperature of an LED. What's even worse
is G9 fittings usually restrict ventilation because the G9 halogens
have to run hotter than they do in free air to achieve full life.
I haven't looked for G9 LEDs, but I doubt anything more than 2W
would last long. If the G9 fitting has some ventilation restriction
which can be removed without reducing safety, then you should do
that when retro-fitting LEDs.

Steer clear of G9 fittings when buying lights - they're a technology
dead-end.

Thanks - yes would avoid in future but they were already here.

They are actually lamps on ceiling fans so, although possible to change,
would be fairly expensive. Air flow is not a problem.

https://www.youtube.com/watch?v=ol-lJ3NDY7A

https://www.youtube.com/watch?v=vbt2ojkXPuo

https://www.youtube.com/watch?v=hliHBeC1sco

And those have precisely what to do with my question?

--
Rod

"polygonum" wrote in message
...
On 10/07/2016 10:40, ARW wrote:
"polygonum" wrote in message
...
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to
be easy to actually push into the receptacles.

Since when have G9's ever fitted properly on the first attempt?

As for the LED verions of G9s I cannot recommend any. I have fitted a
few and I disliked them. A pack of 10 40W halogen G9s is about £7 at my
wholesalers and that is what I am sticking with for now.


Oh dear... :-(

Thanks.


Well Andrew gave you the technical side and I gave you the on hands side
within a few minutes of each other:-)

Mind you an apprentice managed to swap a G9 lamp for a G4 lamp the other
day.

--
Adam

polygonum wrote:
On 11/07/2016 12:49, Weatherlawyer wrote:

https://www.youtube.com/watch?v=hliHBeC1sco

And those have precisely what to do with my question?


Don't hold your breath waiting for a rational answer...

Tim

--
Trolls AND TROLL FEEDERS all go in my kill file

On Sun, 10 Jul 2016 09:33:44 +0000, Andrew Gabriel wrote:

In article ,
polygonum writes:
We need six or so G9 LED lamps.

There are loads available (e.g. on Amazon) but mostly with few and/or
mixed reviews.

Ideally, they be 5 to 7 watts, I'd like them to be about 4-5000 K - so
cool rather than cold. And fit well - quite a few are reported not to
be easy to actually push into the receptacles. Also, want to have them
in about a week - not the indeterminate period common to those sourced
directly from China - as so many are.

Any recommendations?

The G9 lamp format is simply too small for LEDs other than very low
power - there isn't enough surface area to dissipate much power and
remain within the working temperature of an LED. What's even worse is G9
fittings usually restrict ventilation because the G9 halogens have to
run hotter than they do in free air to achieve full life.
I haven't looked for G9 LEDs, but I doubt anything more than 2W would
last long. If the G9 fitting has some ventilation restriction which can
be removed without reducing safety, then you should do that when
retro-fitting LEDs.

Steer clear of G9 fittings when buying lights - they're a technology
dead-end.

Not if the manufacturers (Cree and Philips Lighting) *finally* make good
on their, now 2 1/2 year old, promises that the 280 and 303 Lumens per
watt laboratory samples they'd announced to the trade press along with an
estimated 18 to 24 month lead time for such "Lab Samples" to appear on
shop shelves.

The best efficiency LED amps I've seen range from 70 to 100 Lumens per
watt even now, some 6 months past the expected date for those promised
280 to 300 Lumen per watt lamps to enter the retail distribution chain.

If you can hang on (another year or three?) for these high efficiency
LED lamps, you can have 3W 900 Lumen output lamps that run cooler[1] than
the current 2 watt 140 to 200 lumen lamps we seem to be currently stuck
with. The technology is not a dead end (assuming the manufacturers
finally commercialise their lab samples of 2 1/2 years back).

[1] The cooler running benefit of doubling and tripling the efficiency
over the current 70 to 100 Lumen per watt lamps is significantly greater
compared to say a doubling of efficiency of an incandescent lamp where
some 97 to 98 percent is dissipated as waste heat for a standard 100W
bulb and a doubling of efficiency in this case will only reduce the waste
heat energy from, say 97.5% down to 95%, an almost unmeasurable drop in
temperature of the light fitting itself.

--
Johnny B Good

On Mon, 11 Jul 2016 07:32:30 +0100, polygonum wrote:

On 11/07/2016 02:14, Pet @ www.gymratz.co.uk ;¬) wrote:
Our "above bathroom mirror" lamp had been dead for about 18 months then
I finally decided to try an LED G9.

Went for the biggest one that would fit in the holder.

Can't comment on reliability as it's only been fitted for 8 weeks.
Other family members do have an annoying habit of putting the bathroom
light(s) on ALL the time regardless of whether it's required or not,
then they leave them on so it's getting quite a bit of use.

One I bought has a 5 year warranty so if I get 5 years out of my £4.99
I'll be a happy chap.

One I bought was this one
https://www.ledhut.co.uk/search/?q=4...+Capsule+Shape in
"Daylight" 4000K It's much brighter than the halogen it replaced and
the light is perfect for the bathroom.

Thanks Pete - expensive!

Interesting to see an efficiency of "up to" just 67.5 Lumens per watt
(just one quarter of what Cree had promised would be on shop shelves by 6
months ago - a promise made on the back of their record breaking 303
Lumens per watt lab samples they'd announced to the press two and a half
years ago and likewise for Philips Lighting with their 280 Lumens per
watt lab specimens).

The "Corn Cob" construction (which appears to use some 45 or more chip
LEDs) not only facilitates 360 degree light distribution but eliminates
the need for a heatsink to keep a pair of 2W high power LEDs cool.

Spreading that 4W consumption over some 45 to 60 chip LEDS reduces the
per LED dissipation to below the 90mW mark, almost low enough to be their
own heatsinks (like the TO220 plastic power transistors being able to
dissipate a couple of watts without mounting to a heatsink that would
otherwise allow them to handle up to 90 watts of dissipation in the case
of the highest rated of these plastic power transistors).

I should imagine the fittings were designed not to *overcool* the
original 25 watt halogen lamps since the envelope has to operate at
around the 250 deg C mark to sustain the halogen cycle.

The problem with LEDS is that their maximum junction temperature limit
is a mere 150 deg C or so, requiring that the fitting stays a few tens of
degrees cooler at least in order to dissipate the best part of the 4
watts consumed from the mains supply without the necessary temperature
gradient (required to shift the heat from the diode junctions into the
fitting) causing the LED chips to exceed their maximum temperature limit.

The temperature inside the fitting itself has to also be above ambient
in order to provide a thermal gradient by which to transport that 4 watts
of heat away from the fitting and into its immediate environment - the
successive discrete temperature gradients between the LED junctions and
the immediate environment can add up to a considerable temperature rise
above ambient.

The better the efficiency of the LEDs used, the less of a problem there
is with waste heat since, for a given input wattage, a higher efficiency
LED not only provides greater light output it also reduces the portion of
the input energy that needs to be dissipated as waste heat, a "Win, win"
situation for the even higher efficiency LED lamps that were promised two
and a half years ago. It's a shame they're overdue by 6 months and still
not a sign of them. :-(

--
Johnny B Good

On Tue, 12 Jul 2016 02:06:40 GMT, Johnny B Good wrote:

The best efficiency LED amps I've seen range from 70 to 100 Lumens per
watt even now, some 6 months past the expected date for those promised
280 to 300 Lumen per watt lamps to enter the retail distribution chain.

Nearly a year ago I bought som 5W 600lm COB LEDs, so 120lm/W.
Screwfix has som 'filament' (COB) lamps that do exceed 100lm/W.

It is disappointing that the 'promised' output hasn't yet arrived. I've
enough spares to hang on for a couple of years or so (not had a LED fail yet
- oldest in frequent use is nearly 2), so will wait and see.
--
Peter.
The gods will stay away
whilst religions hold sway

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On 12/07/2016 04:21, Johnny B Good wrote:

Interesting to see an efficiency of "up to" just 67.5 Lumens per watt
(just one quarter of what Cree had promised would be on shop shelves by 6
months ago - a promise made on the back of their record breaking 303
Lumens per watt lab samples they'd announced to the press two and a half
years ago and likewise for Philips Lighting with their 280 Lumens per
watt lab specimens).

The "Corn Cob" construction (which appears to use some 45 or more chip
LEDs) not only facilitates 360 degree light distribution but eliminates
the need for a heatsink to keep a pair of 2W high power LEDs cool.

Spreading that 4W consumption over some 45 to 60 chip LEDS reduces the
per LED dissipation to below the 90mW mark, almost low enough to be their
own heatsinks (like the TO220 plastic power transistors being able to
dissipate a couple of watts without mounting to a heatsink that would
otherwise allow them to handle up to 90 watts of dissipation in the case
of the highest rated of these plastic power transistors).

I should imagine the fittings were designed not to *overcool* the
original 25 watt halogen lamps since the envelope has to operate at
around the 250 deg C mark to sustain the halogen cycle.

The problem with LEDS is that their maximum junction temperature limit
is a mere 150 deg C or so, requiring that the fitting stays a few tens of
degrees cooler at least in order to dissipate the best part of the 4
watts consumed from the mains supply without the necessary temperature
gradient (required to shift the heat from the diode junctions into the
fitting) causing the LED chips to exceed their maximum temperature limit.

The temperature inside the fitting itself has to also be above ambient
in order to provide a thermal gradient by which to transport that 4 watts
of heat away from the fitting and into its immediate environment - the
successive discrete temperature gradients between the LED junctions and
the immediate environment can add up to a considerable temperature rise
above ambient.

The better the efficiency of the LEDs used, the less of a problem there
is with waste heat since, for a given input wattage, a higher efficiency
LED not only provides greater light output it also reduces the portion of
the input energy that needs to be dissipated as waste heat, a "Win, win"
situation for the even higher efficiency LED lamps that were promised two
and a half years ago. It's a shame they're overdue by 6 months and still
not a sign of them. :-(

Wow. Thankyou for an enlightening (NPI) post. And there was me thinking
it was just an expensive bulb that might give more light and less heat.


Cheers - Pete




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In article ,
Johnny B Good wrote:
[1] The cooler running benefit of doubling and tripling the efficiency
over the current 70 to 100 Lumen per watt lamps is significantly greater
compared to say a doubling of efficiency of an incandescent lamp where
some 97 to 98 percent is dissipated as waste heat for a standard 100W
bulb and a doubling of efficiency in this case will only reduce the
waste heat energy from, say 97.5% down to 95%, an almost unmeasurable
drop in temperature of the light fitting itself.

I'm just waiting for the day when I can get a CFL or LED to replace a
standard 150 watt GLS. Or even 100w. Properly. That really does give as
much light.

--
*Remember not to forget that which you do not need to know.*

Dave Plowman London SW
To e-mail, change noise into sound.

Johnny B Good wrote:

a promise made on the back of their record breaking 303
Lumens per watt lab samples they'd announced to the press two and a half
years ago and likewise for Philips Lighting with their 280 Lumens per
watt lab specimens).

Said you were being optimistic to see them on the shelves early :-)

Difficulties in progressing from lab to factory? Or wanting to fleece
everyone once for medium efficiency LEDs then again shortly after for
high efficiency replacements?

The "Corn Cob" construction (which appears to use some 45 or more chip
LEDs) not only facilitates 360 degree light distribution but eliminates
the need for a heatsink to keep a pair of 2W high power LEDs cool.

The lamps with an array of mini-LEDs can cause odd multi-shadowing
effects, depending on whether the shade provides much diffusion of the
light.

On 12/07/2016 15:12, Andy Burns wrote:
Johnny B Good wrote:

The "Corn Cob" construction (which appears to use some 45 or more chip
LEDs) not only facilitates 360 degree light distribution but eliminates
the need for a heatsink to keep a pair of 2W high power LEDs cool.

The lamps with an array of mini-LEDs can cause odd multi-shadowing
effects, depending on whether the shade provides much diffusion of the
light.


Agreed. Some of the more recent LED lamps have vast numbers of very
small emitters. I imagine they help to achieve lower temperature at any
point compared against the large single emitter designs?

--
Rod

In article ,
polygonum wrote:
Agreed. Some of the more recent LED lamps have vast numbers of very
small emitters. I imagine they help to achieve lower temperature at any
point compared against the large single emitter designs?

More likely an attempt to give a reasonably even light output. And
multiple low powered ones are cheaper than a single high powered one.

--
*What do little birdies see when they get knocked unconscious? *

Dave Plowman London SW
To e-mail, change noise into sound.