- Motorola smartphone battery charging - 1 Update
- [Q] dimmer switch for halogen floor lamp - 4 Updates
- PC timing problem - 2 Updates
| coon.mj@gmail.com: Jun 25 08:55AM -0700 On Thursday, 15 June 2017 17:50:56 UTC+1, Jeff Liebermann wrote: > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558 Hi Jeff, apologies for the apparent lack of appreciation for your reply (though some of it was a bit obvious!). I am actually quite familiar with bulging lithium batteries and have a collection of mildly obese ones, mostly due to keeping a device on a charging cradle unnecessarily. Fortunately they are user-replaceable batteries. What is new to me is a non-user-replaceable battery with instructions that state it cannot be damaged by overcharging. However since I am not a mere "user" I have obtained and fitted the new battery. At least disassembly was largely achieved by the battery! A smart phone has enough potential intelligence to cycle its battery through whatever charge/discharge routine is required to keep it in lean health. It is a pity this routine is not enforced... Mike. |
| mikejcomments@gmail.com: Jun 24 02:42PM -0700 On Monday, July 3, 2000 at 3:00:00 AM UTC-4, Yi-Kuen Lee wrote: > homepage: http://www.zingear.com.tw and sent an email to them. They didn't > reply my email. I think they just sell to the big company which makes the lamp. > Yi-Kuen Hello, You can buy the switch from this link: https://www.ceilingfanswitch.com/product/lamp-dimmer-zing-ear-ze-02/ |
| tabbypurr@gmail.com: Jun 24 03:20PM -0700 > Hello, > You can buy the switch from this link: > https://www.ceilingfanswitch.com/product/lamp-dimmer-zing-ear-ze-02/ Do you reckon it's still awaiting repair after 17 years? NT |
| jurb6006@gmail.com: Jun 25 04:53AM -0700 Yeah, another Googler. I am oe but I do not drege up decades old posts, I just use it because... But the thing is you are really not supposed to din halogen lamps because then the halogen is not sufficiently activated to allow the filament to operate in the higher range, which is the whole idea of halogen lamps. Actually I should have not posted because I do not fucking care. |
| Phil Allison <pallison49@gmail.com>: Jun 25 05:09AM -0700 jurb...@gmail.com wrote: ---------------------------- > But the thing is you are really not supposed to din halogen lamps because > then the halogen is not sufficiently activated to allow the filament to > operate in the higher range, which is the whole idea of halogen lamps. ** Yet another dumb myth trotted out by jurb. Dimmed halogen bulbs last just fine - stage lighting has used dimmers and halogen lamps together for decades and get expected life out of them. Hint, when dimmed the filament is cooler and does not NEED the " halogen cycle " to extend its life. ..... Phil |
| Dimitrij Klingbeil <nospam@no-address.com>: Jun 24 08:18PM +0200 On 23.06.2017 04:15, John Larkin wrote: > realtime OS. I don't think I could load a screen and simultaneously > bang a serial port pin, or some USB device, accurate to a > millisecond. Well, probably not. ... > and the screen refresh, are asynchronous. There is probably a way to > synchronize video ram loads with screen refresh, but I'm not > volunteering to write any device drivers. ... Hi John Frankly, I don't think that the various video latencies involved will give you a 1 ms total timing budget. Modern LCD monitors are some complex beasts, they generate their own screen update timing. What you send on the VGA/DVI/HDMI port is no longer synchronous with the LCD "on the glass" drive signals. Especially if the input signal is analog (VGA), the monitor will, after digitizing it, store large chunks and run it through a lot of processing (resize, anti-alias, filters for various "enhancements" such as edge sharpness) before buffering the whole frame in order to be able to output it to the LCD at some potentially unrelated LCD-specific frame rate, which might not even be publicly documented anywhere. So you have 2 areas of non-synchronous behavior: 1. in the graphics card (memory write by a driver vs. video output) 2. in the monitor (received video signal vs. LCD panel refresh) At least Nr. 2 is not under your control, even if you decide to write drivers, plus as soon as different monitors are used, timing won't be repeatable any more. You can use the photodiode trick, but this assumes that the image arrives at the monitor in whole rather than starting somewhere at a random line of the screen, progressing to the last line and then finishing the remaining part from the top. The starting position won't likely be under your control, as won't be the exact time that the LCD panel will take to refresh (plus the frame takes longer than 1 ms). Additionally, the liquid crystals in the LCD itself typically have longer than 1 ms response times plus the response times are voltage-dependent (depend on the content of the picture) and asymmetric (relaxation can be considerably slower than electrostatic alignment), so going from dark to bright is not the same at going from bright to dark, and the actual levels (both absolute and relative) of "bright" and of "dark" also affect timing. The time constants involved are on the order of single digit ms, but this already eats the 1 ms budget. Since quantity and series production are both presumably not an issue, a more likely approach to reach 1 ms timing may be a hardware hack of the monitor itself. Rather than controlling the content of the video stream with precision timing (thwarted by monitor buffering and LCD refresh) it should be much easier to control the LED back light. LCD TVs, and presumably monitors too, tend to have circuit boards for power and for video. The power stuff has 2 or 4 layers and cheap PCB technology as it needs neither BGAs nor controlled impedances, while the video stuff is more complex and costly per PCB area, so they keep the area of the video board to the minimum. The drivers for the back light LEDs tend to be on the power board, not on the video board, and the connection, again for cost reasons, uses the fewest number of wires possible. Often, there is only one single wire that controls the LED state as well as their brightness by using PWM. Hacking a small board with an AND gate into this circuit as well as some ESD protection for good measure should be technically possible (as well as a mounting an SMA jack somewhere). Whatever generates the timing, could then distribute the same signal to the new "light enable" port on the monitor and to the other gear. Dimitrij P.S. Just recently there was a thread on sci.electronics.repair that dealt with light-related issues in TVs and hacking them to get the maximum brightness reduced. Maybe somebody from there can suggest monitor-related info too. |
| bitrex <bitrex@de.lete.earthlink.net>: Jun 24 03:52PM -0400 On 06/24/2017 02:18 PM, Dimitrij Klingbeil wrote: > dealt with light-related issues in TVs and hacking them to get the > maximum brightness reduced. Maybe somebody from there can suggest > monitor-related info too. Killing the backlight is definitely the way to go, but some PC graphics hardware and monitors have a a one-wire interface routed along with the display signal for the monitor to report its capabilities to the OS and for the OS to control the display brightness, independently of the GPU and display hardware. I'd try to get my hands on one of those and see if doing it all via software was fast enough before I started hacking into a monitor! |
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