NiMH self-discharge is about 1% per day, or no more than about 25-30% over 3-4 weeks. When I used separate rechargeable batteries I'd just wait until the mouse acted up, which took about 3 months. Now my mouse recharges whenever I park it in the docking station.
John Navas hath wroth:
Typo error. It should be 675 ma-hr AA NiCad's. I think there are about 100 cells remaining in the box. I use them to rebuild battery packs and in whatever they fit.
This is a much older wireless mouse. Logitech "Cordless Wheel Mouse" model M-RK45. Rating 3V 15ma. Uses two AAA batteries. That might explain the relatively short operating battery life.
The increased capacity should give me much more than 3-4 weeks runtime. At 30% self-discharge per month, I suspect that the NiMH will be effectively "dead" at the same time my NiCads are run down. That's because both my cordless mice were made for the higher voltage alkaline cells. The internal low battery indicator usually starts to complain at what I guess is about 50% of NiCad capacity. It's a complex tradeoff, and I'm too lazy to do the numbers.
I wonder though on the studies if they are looking at one transmitter at one frequency etc. Also there was a new study that flashed across slashdot (I think it was /.) this week that was suggesting the earlier cell phone studies may not have been right and cell phones may not be as safe as we've been lead to believe. Clearly controversy still reins here. My concern is the potential when you have a blue keyboard, mouse, printer, monitor, you know all the little external gadgets that can accumulate on a system (Ive got a USB DVD burner, cheap quick cam floppy drive to name a few on my usb ports that could turn blue). Now toss in a cheap sweat shop made microwave, X10, cordless phone, well again you get the idea. Maybe not a lot of high powerRF, but certainly a lot of spectrum in all those gizmos.
fundamentalism, fundamentally wrong.
You know, I hadn't even considered without the wire what stops the mouse from growing legs and walking off into some deep dark corner that only the cats or dog know about. Thanks for that additional heads up.
fundamentalism, fundamentally wrong.
Some of us are just more human then others
fundamentalism, fundamentally wrong.
I was thinking more of cancer, cataracts, grey hair, early balding, irritable bowels, you know enhanced aging...
Oh!! I thought they were bluetooth gadgets. So the neighbors over modulated CB can make a wireless mouse pointer go crazy? This has the potential for some fun . Tell me more, besides making the hams on
10 meters hate me, how many mice could I screw with if I had a really serious boot leg linear for the old CBYes, but in time even they wear out, Duke while horrid in ice storms is pretty good most of the time and hasn't worn out yet... Of course ask me after they break ground for the new licensed nuke in Gaffney, SC.
fundamentalism, fundamentally wrong.
Couple things Bob, I use these gadgets, got the cell phone as you note, wifi network (why would any of us be in this newsgroup otherwise ), bluetooth link to my pda to sync with Outlook (appointments etc). As noted no wireless mice of kybds yet, but that's more a battery issue then concern over RF. I just wonder as these gadgets proliferate if it won't be having a negative impact on us. As a ham (I noticed your sig) I'm sure you've experienced the down the street in the past who bought a cheap TV that leaked rf all over the place (it was your fault it interfered with the other neighbor's radio or tv, d*mned hams ). I realize there is no escape, I just wonder if this can be good for us over the long term. Especially when you add small children into this ever increased rf environment around the home. What's harmless for you and me can be a cumulative problem for children over the decades. I'm not saying we should forgo these things, I just am wondering.
fundamentalism, fundamentally wrong.
Does that mean my tinfoil beanie
fundamentalism, fundamentally wrong.
rico snipped-for-privacy@hotmail.com (Rico) hath wroth:
That manner of symptoms are very difficult to produce statistically signifigant data. Just collecting the data for such problems requires long term controlled studies.
A few use Bluetooth. Most are 27Mhz.
rico snipped-for-privacy@hotmail.com (Rico) hath wroth:
There are LOTS of things wrong with the students tinfoil hat test. For example, using a network analyzer instead of a spectrum analyzer to measure radiation. No mention of SAR (specific absorption rate). Lots more. What they did was demonstrate something that should be intuitive. Take a small object and light it up with a desk lamp. The front is illuminated while the back is dark. Now, put a reflective mirror behind the object. The front is still illuminated, but now the back gets some light. Same with your head and any nearby metal reflector.
Personally, I think the kitchen collander hat is a better fashion statement.
rico snipped-for-privacy@hotmail.com (Rico) hath wroth:
Ok, let's get serious for just a moment (and only just a moment). Methinks this is worth a read:
But the holes!!!!
fundamentalism, fundamentally wrong.
Be fair to them - a whole lot of _real_ science is done (and must be done) to verify "something that should be intuitive". This was intended as a joke.
Think Faraday cage.
About a teaspoon, if applied correctly...
You should visit the two websites in question. After a quick visit to both, I think you will understand the redundancy of this last statement.
fundamentalism, fundamentally wrong.
Interesting read, but very interesting that he uses sunlight as one of his EM field examples, I have a good friend (outdoorsman of the first order) who is on a regular basis now at the dermatogolists have those little pre-cancerous bumps burned off his arms and scalp.
Don't misunderstand me Jeff, I am not saying we should put a hold on these devices, I just wonder about the long term safety as these device proliferate in our homes and lives. Is any one or two of them a problem, I would doubt it, but keyboards, mice, cell phones, cordless phones, well you know the list of devices better then I do, they make me wonder. I certainly wouldn't stop the development or sale of these things. The little bluetooth headsets for cell phones are cool, but there again rf + a little more rf
fundamentalism, fundamentally wrong.
Yep.
- Sunlight generates about 1000 watts of power per square meter (or 100 milliwatts/cm^2).
- The maximum RF exposure limit is 1 milliwatt/cm^2 for an uncontrolled environment. Therefore, standing in the sun exceeds the FCC exposure limits by 100 times.
I have a very simple view of such things. EVERYTHING is unsafe in sufficient quantity and exposure levels. There isn't a single activity or device that cannot be considered in some way detrimental to one's health. What distinguishes those that are deemed "safe" from those that are "dangerous" are relative risks, odds, numbers, and probabilities. Work out the numbers and worry about those things that are numerically important. For example, because RF fields vary with the square of the distance, and bulk exposure with the cube of the distance, the only things that are really important are very close sources, and perhaps very powerful sources (broadcast, solar, radar, etc).
Incidentally, in the distant past, I did some work for an insurance actuary calculating values and probabilites. It taught me that one can attach a value and a risk factor to literally anything. When someone says that the risks cannot be calculated, they probably don't know how to do it, or what they're talking about.
Fine. We'll attach a warning label to the Bluetooth headset. Maybe make you sign a disclaimer and limitation of liability document before being allowed to operate one. Maybe force you to get an FCC license that includes a class and exam on safe RF practices. Will that make you "feel" safe?
alight already,,,,, This is the damnest post I ever got into or viewed,, KA,,
Bob NA6t Northern California --- North of 'NO RF MENDOCINO"
BUT,,, we got lots of POT, ah hell I guess they'll both make you see things,,
FDA to review wireless phone safety
It wants to evaluate latest research in wake of controversial Swedish study
APRIL 06, 2006 (REUTERS) - WASHINGTON -- The U.S. Food and Drug Administration said today that it will review wireless phone safety after a recently published study that raised concerns about a heightened risk of brain cancer.
Swedish researchers said last month the use of cellular phones over a long period of time can raise the risk of brain tumors (See "Study: Long-term mobile phone use raises brain tumor risk"). Their findings contradict a number of earlier studies and are "difficult to interpret," the FDA said in comments posted on its Web site.
Still, the agency said it "plans to convene a meeting in the near future to evaluate research conducted to date in this area and identify gaps in knowledge that warrant additional research."
[MORE]
These are all very low level sources, and operate on a small number of frequencies. I'd personally worry more about cosmic rays or getting hit by a meteorite. YMMV.
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