Codeman
Flashlight Enthusiast
- Joined
- Nov 26, 2004
- Messages
- 2,690
My A2/Red Surefire is doing something that seems rather strange to me.
A few days ago, it began showing 2 distinctly different output levels from the incandescent bulb. I thought regulation would prevent this from happening, but it appears that there is a voltage range where the regulation is failing.
A2 LED only (exposure was 1/4 s, F/3.5):
A2 on Incandescent, but low output (exposure was 1/14.2 s, F/3.5):
A2 on Incandescent, normal output (exposure was 1/64 s, F/3.2):
A few things to note:
<ul type="square">[*]all three pictures were taken with both the original bulb and original SF123's
[*]exposure was NOT locked for the 3 shots, so overall brightness between the 3 can't be compared
[*]no post-processing has been done, except for resizing and converting to PNG format
[*]the amount of red light in the 2nd picture clearly shows that the incandescent is not at its normal level
[*]the beam for the third shot was quite a bit brighter, but the camera compensated with a much faster shutter speed, so the difference isn't captured in the pictures
[*]the output of the LED's in the 3rd picture was not visible to my eyes, though a slight bit of red can be seen in the picture
[*]the 2-level incandescent output started around 2.90V/cell[*]the normal incandescent output level was reached once the light was on for a few seconds, but for a while, I could turn the light off, then back on and the low level would return, then jump back up to normal output
[*]now that both batteries have dropped to 2.85V, only the low level of incandescent output occurs - the normal level is no longer available
[*]with new batteries, the normal incandescent always occurs[/list]
I didn't post a 4th shot showing incandescent output with new SF123's, because it's indistinguishable from the third picture above.
As you can see in the second picture, the incandescent output is roughly the same as the LED, which is extremely low for the incandescent. But, since new batteries return the incandescent output to normal (3rd picture), the only explanation I can come up with is that for a small voltage range, about 2.9-2.85V/cell, regulation fails intermittently.
Have any other A2 owners seen this? If not, does this seem to indicate a possible problem with my particular A2's regulation circuitry? Or an I just blessed with a quirky A2? Or, is this normal?
Of more interest, however, is whether anyone can explain this bizarre quasi-regulation. My U2, once regulation at a particular level is lost, it never goes back up. Well, it might if I turned it off, then back on, but never has it jumped back up while the light was on. That is what my A2 was doing.
A few days ago, it began showing 2 distinctly different output levels from the incandescent bulb. I thought regulation would prevent this from happening, but it appears that there is a voltage range where the regulation is failing.
A2 LED only (exposure was 1/4 s, F/3.5):
A2 on Incandescent, but low output (exposure was 1/14.2 s, F/3.5):
A2 on Incandescent, normal output (exposure was 1/64 s, F/3.2):
A few things to note:
<ul type="square">[*]all three pictures were taken with both the original bulb and original SF123's
[*]exposure was NOT locked for the 3 shots, so overall brightness between the 3 can't be compared
[*]no post-processing has been done, except for resizing and converting to PNG format
[*]the amount of red light in the 2nd picture clearly shows that the incandescent is not at its normal level
[*]the beam for the third shot was quite a bit brighter, but the camera compensated with a much faster shutter speed, so the difference isn't captured in the pictures
[*]the output of the LED's in the 3rd picture was not visible to my eyes, though a slight bit of red can be seen in the picture
[*]the 2-level incandescent output started around 2.90V/cell[*]the normal incandescent output level was reached once the light was on for a few seconds, but for a while, I could turn the light off, then back on and the low level would return, then jump back up to normal output
[*]now that both batteries have dropped to 2.85V, only the low level of incandescent output occurs - the normal level is no longer available
[*]with new batteries, the normal incandescent always occurs[/list]
I didn't post a 4th shot showing incandescent output with new SF123's, because it's indistinguishable from the third picture above.
As you can see in the second picture, the incandescent output is roughly the same as the LED, which is extremely low for the incandescent. But, since new batteries return the incandescent output to normal (3rd picture), the only explanation I can come up with is that for a small voltage range, about 2.9-2.85V/cell, regulation fails intermittently.
Have any other A2 owners seen this? If not, does this seem to indicate a possible problem with my particular A2's regulation circuitry? Or an I just blessed with a quirky A2? Or, is this normal?
Of more interest, however, is whether anyone can explain this bizarre quasi-regulation. My U2, once regulation at a particular level is lost, it never goes back up. Well, it might if I turned it off, then back on, but never has it jumped back up while the light was on. That is what my A2 was doing.
