HIMNL9
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Ok, here are some results from the tests i made on the A140, before mangl ..... er, "dismantle" it 
.....
First, tested it as "bare" projector, on request, and took some pics from it, compared with the old 1500 lumen of a friend ..... it's more luminous, but i really doubt that it reach the 2500 lumen that the producer claim ..... also, the light is more "cold" than a standard type (more ice-white), and it lack of a "true" color balancement function in the menu ..... i've took pics at the different "eco modes", but the difference is not too much ..... also, it have a worse focusing capability, related to fine details (but the old one had an objective of 15cm dia, and this surely influence the focusing and image quality)
BTW, the Casio one is the image on the right
Extremely noisy in no-eco mode too, due to the low diameter of the fans and the consequent high speed.
Then, i took the hatchet, and started some internal tests ..... i've used a 0,2 ohm 3W resistor in serie to two of the loops for current measure (once i've seen that the two was identical, have not repeated the same measures also on the others).
The diodes are drived with a "square" signal, with a duty cycle of 8,3mS (that, if i remember how to use a calculator, means 120Hz PWM driving) ..... but it was not perfectly "squared", at the turning-off fronts, there was like a small "disturbed step" (the damn webcam refuse to take oscilloscope snapshots ..... i have to invent something for this, first or after ) ..... anyway, the total "ON" time was around 60% of the duty cycle, with a peak current of 1,84A ..... that in eco1 , this means a medium current of 1100mA ..... out from the eco function, it was drived around 80% of the duty cycle, this give a medium current of 1470mA, and in eco2 mode, the signal was approximatively the 40 - 45% of the duty cycle, giving a medium current of 820mA. (some commercial advertisements was talking about an "eco3 mode", but on the menu of the unit that i had, there was no "eco3" mode)
Power reading from single diodes in the different modes was, with minimal differences, the same from all the diode series, and was (rounded medium values) 1690mW in no-eco mode, 1370mW in eco1 mode, and 945mW in eco2 mode ..... anyway, i had to make all the measures very quickly, between the cooling pauses, so some of these values can be influenced from the different initial temperatures and the different speeds in which the temperature rises, for the different conditions ..... i guess that some decent (and more professionally made) measures can be made only in "external" conditions, like, taking a diode away from the module, reassembling the module, placing the harvested diode in an external heatsink, and so on, but i had not available the needed items for do that, nor had the time for that, sorry.
The heat production was impressive, i had to stop frequently and make long pauses, especially in no-eco mode ..... also with the fans running at maximum speed, the fins becomed so hot that was almost impossible to keep a finger on them ..... i had no thermometer, but i guess a good 80C was all there
Anyway, these measures are only indicative, not absolute ..... i had only one projector for test it, and have no A130, nor any data from an A130 to compare with the ones i took, so, don't know if we can say that the diodes are effctively different diode types, or if they are the same type, but "cherry-picked" or selected lots, or whatever ..... does someone can do the same tests on an A130, for have some data to compare ?
I also tried to take a pair of "macro" of the diode, but the "professional macro extension" of my webcam (a lens set glued on the cam with duct tape 
) suck a bit, and have a field depth of less than 2mm, so the result is not so good ..... enough for see that these chips are relatively long, and have at least 3 wires for each pole ..... guess that without decan one of them, there's no way for take better images (not with my cam, at least ..... anyone have a dead diode to decan for take some decent macros ? )
..... First, tested it as "bare" projector, on request, and took some pics from it, compared with the old 1500 lumen of a friend ..... it's more luminous, but i really doubt that it reach the 2500 lumen that the producer claim ..... also, the light is more "cold" than a standard type (more ice-white), and it lack of a "true" color balancement function in the menu ..... i've took pics at the different "eco modes", but the difference is not too much ..... also, it have a worse focusing capability, related to fine details (but the old one had an objective of 15cm dia, and this surely influence the focusing and image quality)
BTW, the Casio one is the image on the right
Extremely noisy in no-eco mode too, due to the low diameter of the fans and the consequent high speed.
Then, i took the hatchet, and started some internal tests ..... i've used a 0,2 ohm 3W resistor in serie to two of the loops for current measure (once i've seen that the two was identical, have not repeated the same measures also on the others).
The diodes are drived with a "square" signal, with a duty cycle of 8,3mS (that, if i remember how to use a calculator
, means 120Hz PWM driving) ..... but it was not perfectly "squared", at the turning-off fronts, there was like a small "disturbed step" (the damn webcam refuse to take oscilloscope snapshots ..... i have to invent something for this, first or after ) ..... anyway, the total "ON" time was around 60% of the duty cycle, with a peak current of 1,84A ..... that in eco1 , this means a medium current of 1100mA ..... out from the eco function, it was drived around 80% of the duty cycle, this give a medium current of 1470mA, and in eco2 mode, the signal was approximatively the 40 - 45% of the duty cycle, giving a medium current of 820mA. (some commercial advertisements was talking about an "eco3 mode", but on the menu of the unit that i had, there was no "eco3" mode)Power reading from single diodes in the different modes was, with minimal differences, the same from all the diode series, and was (rounded medium values) 1690mW in no-eco mode, 1370mW in eco1 mode, and 945mW in eco2 mode ..... anyway, i had to make all the measures very quickly, between the cooling pauses, so some of these values can be influenced from the different initial temperatures and the different speeds in which the temperature rises, for the different conditions ..... i guess that some decent (and more professionally made
) measures can be made only in "external" conditions, like, taking a diode away from the module, reassembling the module, placing the harvested diode in an external heatsink, and so on, but i had not available the needed items for do that, nor had the time for that, sorry.The heat production was impressive, i had to stop frequently and make long pauses, especially in no-eco mode ..... also with the fans running at maximum speed, the fins becomed so hot that was almost impossible to keep a finger on them ..... i had no thermometer, but i guess a good 80C was all there
Anyway, these measures are only indicative, not absolute ..... i had only one projector for test it, and have no A130, nor any data from an A130 to compare with the ones i took, so, don't know if we can say that the diodes are effctively different diode types, or if they are the same type, but "cherry-picked" or selected lots, or whatever ..... does someone can do the same tests on an A130, for have some data to compare ?
I also tried to take a pair of "macro" of the diode, but the "professional macro extension" of my webcam (a lens set glued on the cam with duct tape
) suck a bit, and have a field depth of less than 2mm, so the result is not so good ..... enough for see that these chips are relatively long, and have at least 3 wires for each pole ..... guess that without decan one of them, there's no way for take better images (not with my cam, at least ..... anyone have a dead diode to decan for take some decent macros ? )
