Are HDS EDU's PWM Controled?

I read something about how the rate of PWM is how the HDS controls its dimming... i always thought it was non-pwm...

however this morning I took my HDS on low... and shook it in my hand while looking at the LED... I saw a bunch of dots rather than one line of light...

???

I thought they were also, which is why some report hearing a low buzzing noise?

Ryan

I think that some of the HDS lights hum because they don't know the words.

I don't know about the higher levels, but I know the lower levels are.

I hear humming on the max, it tells me the battery is almost too low to maintain max brightness.

I tried low brightness and I noticed the line of dots when I shook it too. I can't notice at 10lumens though.

PWM is the recommended way to dim a Lux. Look up the white paper by Henry in his site. Most, if not all of the dimmable multilevel lux lite are pwm dimmed, including mr bulk lion series with controller pcb by Goerges, DJpark with POP and some others.

Sub_Umbra said:

I think that some of the HDS lights hum because they don't know the words.

Click to expand...

:bow: :lolsign:

Sub_Umbra said:

I think that some of the HDS lights hum because they don't know the words.

Click to expand...

:bow: :bow::lolsign: :lolsign:

Kevin Tan said:

PWM is the recommended way to dim a Lux. Look up the white paper by Henry in his site. Most, if not all of the dimmable multilevel lux lite are pwm dimmed, including mr bulk lion series with controller pcb by Goerges, DJpark with POP and some others.

Click to expand...

Its true that it is much easier to make a multilevel lux light using PWM dimming. While there are a few two level lights with current regulated dimming (like the McLux PD, HD45, CR2 Ion) they are in the minority. And the Surefire U2 is the only light I can think of with more than two levels of current regulated dimming.

PWM dimming has an advantage in that color shift of the LED is less pronounced at differing power levels, but it is inferior to current regulated dimming in LED efficiency (light output/power in).

The HDS EDC uses a combination of constant power regulation and PWM dimming. The reason for that is to achieve high efficiencies on the higher levels (where constant power regulation is used) and a constant tint on the lower levels (where PWM is used to let the current not become too low).

Spacemarine said:

The HDS EDC uses a combination of constant power regulation and PWM dimming. The reason for that is to achieve high efficiencies on the higher levels (where constant power regulation is used) and a constant tint on the lower levels (where PWM is used to let the current not become too low).

Click to expand...

whats another light that does the same thing???? The Proton

(now before you flame me... yes I know its regulation isn't that of an EDC.. but its using a 1xAA so give it some slack!)

The color shift when dimming without PWM is even more noticible with some colored emitters. CYAN, for instance, drops to green :sigh: when dimed slightly by lowering the voltage.