Ahh, we are all human and it has been many years since I was really into this but you are correct. Ohm's law is what I said but that only concerns one half the equation (the resistance) the power requirements are the same as long as all of the resistors are of the same R value otherwise the one with the least amount of resistance will demand the most amount of P (wattage).
btw, I see it flicker on the camera due to how camera work but I take it the lamp is flickering at 60hz, right?
@GhostOfACPast It’s all good. … Actually the light was a CFL, so a higher frequency, but I’m sure it still affected it. But the camera for this old video was a cheap snapshot. For the others I used a Nikon D5000 to record HD video.
@adamlhumphreys Yeah, no matter what camera you use you will see light with it that you can't see with the human eye and it will see flicker that your persistence of vision doesn't. I figure it will flash off 30 times a second and on 30 times a second so 60 times a second (like the majority of FLs do) for a 60hz ac source.
btw, what is the led that you used?
I always wanted to put in those high power babies in a retrofit LED night light project (more power).
@GhostOfACPast That’s true, it was probably flickering due to the 60Hz, but since it’s usually rectified (full bridge), it was probably flashing 120 times a second. But since the camera can only capture about 30fps, it probably did flash 30 times a second. Too bad they can’t fit a bigger capacitor in CFLs.
I think the LED was 40,000mcd. And yes, I’d like to get one of those high power babies also. I found one LED die (was like a CPU) that was 100 watts (needed big HS). That would be awesome!
@adamlhumphreys To make sure of my calculations I downloaded the software you used for this and had it scope out the point at the led and it was 60hz but only a half wave. The other half was at 0 so that was the 30 times off I mentioned. If that was a full wave rectifier it would still be a half wave but more frequently. Wiki rectifier.
Yeah, I saw that LED and one that had a Million candle power? LOL, hook that sucker up as a night light, hahahaha. Though the led alone was 24 dollars.
@GhostOfACPast Oh, sorry. I thought you were talking about the CFL. Yes, the LED would be flashing at 60Hz. However, I still don’t see where you got 30. One cycle consists of a positive half wave and a negative half wave occurring every 1/60th of a second. W/ a half bridge, you just flatten a half cycle during 1/60th of a second. So the LED will be both on & off during 1/60th of a second, or 60 a second.
Personally, I’d like to use a high power LED for my headlights (but not to blind ppl)!
@adamlhumphreys I am thinking in binary where the peak is 1 volt and the flat part is 0 volts (max volt and 0 volt).
In half wave rectification, either the positive or negative half of the AC wave is passed, while the other half is blocked. The blocked part is the flat part of the wave or 0 volts (for all practical purposes) hence the 30 times a second on and 30 times a second off since the rectifier (the diode) is not able to give us a constant DC voltage.
@adamlhumphreys Yep. Full wave bridge (4 diodes in a square configuration with two taps at direct opposite sides) will double the frequency but a half wave rectifier will still be 60hz only the down (flat) time is the off. So, the led will flash off 60 times and flash on 60 times in the states (60hz mains frequency). I was thinking 30 but it is 60 as you said. I wonder how much harder that circuit would be with 4 diodes in place of the 1 to get less ripple and have 120hz?
@GhostOfACPast The LED night light replacement bulbs that I have, the ones you can buy, actually do use a full wave rectifier. I probably would’ve used a full bridge with the 4.7k resistors (more room on the board), but it was fairly bright enough. Had I used a board w/o tracing (similar to the cheap, brittle RadioShack boards, but not cheap and brittle), I might’ve done it. Plus I wanted to keep it simple for this tutorial and I'm saving those 4.7k guys for a half-sphere orange juice carton cap
Ohm's Law says that in parallel the resistances decrease (actual ohm's law is something like 1/(1/R)+(1/R)+...) whereas the wattage ability increases (as in 2 48k resistors 1/2 watt in parallel would be 24k 1w) . So, when you said in series that will increase the resistance but the wattage ability will remain the same (2 48k 1/2w in series is 96k 1/2w) since they are not sharing the load as they would be in parallel.
@GhostOfACPast Hey, thanks for the sub & comments! I do appreciate correction of things I may say since I’m human. However, I’ll try to explain why I’m correct in saying a series configuration also increases power capability. If it weren’t true, then the 1/4W resisters would burn to a crisp. In fact, in LED replacement night light bulbs (rated at 1.7W), you will find 5 or so 2.2k 1/4W series resistors inside. Since they’re enclosed & right at their power rating, they get warm, but they do work.
@GhostOfACPast When a voltage drop occurs across a resistor, power (heat) is dissipated. Consider the drop across a 4.7k resistor vs the drop across a 2.2k. A greater drop would be present over the 4.7k, dissipating more heat than the 2.2k. But with two 2.2k resistors in series for 4.4k, half the voltage drop would occur across one while the other half would occur across the other.
Ahh, we are all human and it has been many years since I was really into this but you are correct. Ohm's law is what I said but that only concerns one half the equation (the resistance) the power requirements are the same as long as all of the resistors are of the same R value otherwise the one with the least amount of resistance will demand the most amount of P (wattage).
btw, I see it flicker on the camera due to how camera work but I take it the lamp is flickering at 60hz, right?
GhostOfACPast 9 months ago
@GhostOfACPast It’s all good. … Actually the light was a CFL, so a higher frequency, but I’m sure it still affected it. But the camera for this old video was a cheap snapshot. For the others I used a Nikon D5000 to record HD video.
adamlhumphreys 9 months ago
@adamlhumphreys Yeah, no matter what camera you use you will see light with it that you can't see with the human eye and it will see flicker that your persistence of vision doesn't. I figure it will flash off 30 times a second and on 30 times a second so 60 times a second (like the majority of FLs do) for a 60hz ac source.
btw, what is the led that you used?
I always wanted to put in those high power babies in a retrofit LED night light project (more power).
GhostOfACPast 9 months ago
@GhostOfACPast That’s true, it was probably flickering due to the 60Hz, but since it’s usually rectified (full bridge), it was probably flashing 120 times a second. But since the camera can only capture about 30fps, it probably did flash 30 times a second. Too bad they can’t fit a bigger capacitor in CFLs.
I think the LED was 40,000mcd. And yes, I’d like to get one of those high power babies also. I found one LED die (was like a CPU) that was 100 watts (needed big HS). That would be awesome!
adamlhumphreys 8 months ago
@adamlhumphreys To make sure of my calculations I downloaded the software you used for this and had it scope out the point at the led and it was 60hz but only a half wave. The other half was at 0 so that was the 30 times off I mentioned. If that was a full wave rectifier it would still be a half wave but more frequently. Wiki rectifier.
Yeah, I saw that LED and one that had a Million candle power? LOL, hook that sucker up as a night light, hahahaha. Though the led alone was 24 dollars.
GhostOfACPast 8 months ago
@GhostOfACPast Oh, sorry. I thought you were talking about the CFL. Yes, the LED would be flashing at 60Hz. However, I still don’t see where you got 30. One cycle consists of a positive half wave and a negative half wave occurring every 1/60th of a second. W/ a half bridge, you just flatten a half cycle during 1/60th of a second. So the LED will be both on & off during 1/60th of a second, or 60 a second.
Personally, I’d like to use a high power LED for my headlights (but not to blind ppl)!
adamlhumphreys 8 months ago
@adamlhumphreys I am thinking in binary where the peak is 1 volt and the flat part is 0 volts (max volt and 0 volt).
In half wave rectification, either the positive or negative half of the AC wave is passed, while the other half is blocked. The blocked part is the flat part of the wave or 0 volts (for all practical purposes) hence the 30 times a second on and 30 times a second off since the rectifier (the diode) is not able to give us a constant DC voltage.
GhostOfACPast 8 months ago
@GhostOfACPast I can only see that happening at 30Hz.
adamlhumphreys[dot]com[slash]~stuff[slash]60Hz[dot]gif
adamlhumphreys 8 months ago
@adamlhumphreys Yep. Full wave bridge (4 diodes in a square configuration with two taps at direct opposite sides) will double the frequency but a half wave rectifier will still be 60hz only the down (flat) time is the off. So, the led will flash off 60 times and flash on 60 times in the states (60hz mains frequency). I was thinking 30 but it is 60 as you said. I wonder how much harder that circuit would be with 4 diodes in place of the 1 to get less ripple and have 120hz?
GhostOfACPast 8 months ago
@GhostOfACPast The LED night light replacement bulbs that I have, the ones you can buy, actually do use a full wave rectifier. I probably would’ve used a full bridge with the 4.7k resistors (more room on the board), but it was fairly bright enough. Had I used a board w/o tracing (similar to the cheap, brittle RadioShack boards, but not cheap and brittle), I might’ve done it. Plus I wanted to keep it simple for this tutorial and I'm saving those 4.7k guys for a half-sphere orange juice carton cap
adamlhumphreys 8 months ago
@adamlhumphreys I wanna see that one. :)
GhostOfACPast 8 months ago
@GhostOfACPast I'll let you know.
adamlhumphreys 8 months ago
@GhostOfACPast Wait, I did use the Nikon D5000 for this. It must have been the higher CFL frequency.
adamlhumphreys 9 months ago
Ohm's Law says that in parallel the resistances decrease (actual ohm's law is something like 1/(1/R)+(1/R)+...) whereas the wattage ability increases (as in 2 48k resistors 1/2 watt in parallel would be 24k 1w) . So, when you said in series that will increase the resistance but the wattage ability will remain the same (2 48k 1/2w in series is 96k 1/2w) since they are not sharing the load as they would be in parallel.
GhostOfACPast 9 months ago
@GhostOfACPast Hey, thanks for the sub & comments! I do appreciate correction of things I may say since I’m human. However, I’ll try to explain why I’m correct in saying a series configuration also increases power capability. If it weren’t true, then the 1/4W resisters would burn to a crisp. In fact, in LED replacement night light bulbs (rated at 1.7W), you will find 5 or so 2.2k 1/4W series resistors inside. Since they’re enclosed & right at their power rating, they get warm, but they do work.
adamlhumphreys 9 months ago
@GhostOfACPast When a voltage drop occurs across a resistor, power (heat) is dissipated. Consider the drop across a 4.7k resistor vs the drop across a 2.2k. A greater drop would be present over the 4.7k, dissipating more heat than the 2.2k. But with two 2.2k resistors in series for 4.4k, half the voltage drop would occur across one while the other half would occur across the other.
adamlhumphreys 9 months ago