The human ear + human brain synergy is an amazing tool for picking information out of noise. Hasn't just about everybody been in a crowded area with lots and lots of background noise, and yet been able to figure out what the other person is saying, by sort of mentally focusing on the subject?
And who amongst us isn't old enough to remember SSB? ;-) You can pick voice information out of an incredible amount of noise!
Cheers! Rich
quality'
I remember reading years ago that the spoken human voice could be intelligible at a quite high distortion level. I think the amplifier in question was 30% or somesuch, but that sounds high even to me now. Depending on the venue, even room acoustics may outweigh any distortion issues, I'd guess. Think of the US National Anthem sung at a sports venue...
"for th or e la and e nd of...you get my drift. :-)
Tom
So I think our point is the same, or at least similar...the human voice, when spoken, possibly doesn't require the same low distortion for reasonable intelligibility.
Tom
Hello Spehro,
In a sports arena it will also have to do with the amount of booze that was consumed.
Regards, Joerg
Hello Richard,
Yes, it seems so. It could be the carriers since their currency is kb/sec. Yesterday a long time friend called me on his cell phone. I could not even recognize who it was until several seconds into the conversation, and initially only by what he was talking about.
Regards, Joerg
single
to
concern,
Of course, since all of your above comments still apply.
Now try ganging 6 alkaline watch batteries together instead. There is no mystery here. If one uses exactly the same battery technology in each case, the larger battery will have more storage capacity. (packaging excepted of course, and in the case of six separate cells, this will usually increase) So the answer may be to use a larger 9V battery. Unfortunately these aren't common any more. Most people prefer to use the smaller size, and change it more often.
MrT.
They need to save their bandwidth for pictures & video....
jak
Hasn't someone already mentioned the 6X AAA pack? Only a few mm bigger than a 9V, but lasts considerably longer? There are such a thing as AAA NiMHs, aren't there? My magical charger seems to think so:
I swear, that little box is smarter than I am [not that that's that great of an accomplishment] when it comes to charging NiMHs.
And does anybody remember "The Secret of NIMH"?
Cheers! Rich
But so far we have not been able to even think of approaching the speed and functionality of the human brain with any kind of computer. There were seveal levels of "intelligence" operating to decode CW in heavy QRM/QRN.
On a bit-by-bit basis, probably not. But on a symbol basis, where a symbol is a word, probably so. Especially if the vocabulary is small and there's surrounding context.
It's just a matter of defining "symbol."
John
Hello Mr.T,
Since AA packs a lot more Watthours per cubic inch than a 9V I think it would great if all designers wised up and designed their stuff to work with AA or a couple of them. It's not rocket science. I had a radio
30-some years ago that worked nicely with two AA. It boasted the longest runtime on one set of any radio I ever had. Got lost in a move and now I am using a 9V radio. It doesn't even last a day and the batteries cost twice as much.Regards, Joerg
Hello Jak,
Let's see how that goes. Maybe it's like with pool heaters. People love it until that first bill arrives in the mail.
Regards, Joerg
Hello Rich,
Hey, I am old enough to remember CW. With morse code it has been said that the trained ear was on occasion able to beat Shannon's law. Depends on the imbabitation status though.
Regards, Joerg
What amazes me is the cost of text-messaging. Why do I want to do that again?
I've ditched my land-line and gone cell, but there are many things that make no sense. Land-lines are expensive because the government decides it is so, but that doesn't excuse the cell companies from sanity. Sure, I know, it's all the teeny-boppers that think text-messaging is cool.
-- Keith
...and if the data-rate exceeds Shannon, your "symbol" is defined wrong. ;-)
The other thing people forget is the institutional and personal information that preceeds the communication. Many CWers knew the "fist" of others and their "expressions". This information was transmitted, albeit via a side-channel. ...data comperession with a known dictionary, as it were.
-- Keith
I've clocked high-pass (300Hz) signals through a 3Khz flip-flop. Surprisingly good, using a speech radio station as a signal source.
Typing a text-message in on my phone is going to save me time? OTOH, their time is certainly cheaper.
Huh?
Huh^2?
-- Keith
Time?
If you feel comfortable talking to people by just reciting a message, then you can probably get it done faster/cheaper.
But, how often is that the case? Many people on the other end will digress into weather/how their dog is/...
Comparing the consumer cells/batteries at a given point in time from one manufacturer (GP), you have the capacity of their highest capacity AA cells is typically 2450mAh (marked "2500"), while(st) their highest capacity 9V battery is 210mAh (marked 200). Since the 9V battery is 7 cells in series, the 9V battery has only 60% of the energy storage capacity of the AA cell.
On a weight basis, the 9V battery is 42.5g and the AA cells is 31g, so the AA cell comes out even further ahead (2.28:1).
On a volume basis, the AA cell fits in a cylinder 14.5mm diameter by
50.5mm long (including the end button), so 8339mm^3. The 9V battery fits in a box 48.5mm x 26.5mm x 15.7mm (including the snaps) or 20,180mm^3.On a volume basis, the AA cell comes out ahead by 4:1. If you more realistically use a box (rectangular prism) that just encloses the AA cylinder for the occupied volume, it's still ahead by more than 3:1.
Best regards, Spehro Pefhany
-- "it\'s the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
Pry apart a 9V and you will see why the AA packs more energy per unit volume. There is a lot of the internal space used up by the need to interconnect the cells and isolate them from each other.
I suspect that the cells in the 9V are actually a little better than the AA in energy per volume but I don't think it is by enough to make up for the about 1/3rd of the space that is not actually a cell.
-- -- kensmith@rahul.net forging knowledge
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