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Amplifier transistor matching?

T

Tom MacIntyre

Jan 1, 1970
0
Years ago, I heard a demo of the human voice with 1-bit resolution. It
was understandable, but not at all pleasant.

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
 
J

Joerg

Jan 1, 1970
0
Hello Spehro,

In a sports arena it will also have to do with the amount of booze that
was consumed.

Regards, Joerg
 
R

Richard Crowley

Jan 1, 1970
0
"Tom MacIntyre" wrote ...
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.

And cell-phone manufacturers regularly plumb the depths of
low-res to see how much we will put up with! :)
 
J

Joerg

Jan 1, 1970
0
Hello Richard,
And cell-phone manufacturers regularly plumb the depths of
low-res to see how much we will put up with! :)

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
 
R

Rich Grise

Jan 1, 1970
0
Hello Spehro,


In a sports arena it will also have to do with the amount of booze that
was consumed.
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
 
M

Mr.T

Jan 1, 1970
0
BCTweaker said:
A good reason is because a 9V can't source as much current as even a single
AA cell for the same duration due to their much smaller individual cells.
There are six seperate 1.5V cells connected in series to produce the 9
volts. The cells internal electrodes have significantly less surface area to
interact with a much reduced quantity of electrolyte. If you still need 9
volts for a circuit try ganging six AA's in series. If weight is a concern,
even AAA cells aranged in a battery of 9 volts will outlast most 9V's.

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.
 
J

jakdedert

Jan 1, 1970
0
Joerg said:
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

They need to save their bandwidth for pictures & video....

jak
 
J

Joerg

Jan 1, 1970
0
Hello Mr.T,
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.

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
 
J

Joerg

Jan 1, 1970
0
Hello Jak,
They need to save their bandwidth for pictures & video....

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
 
J

Joerg

Jan 1, 1970
0
Hello Rich,
And who amongst us isn't old enough to remember SSB? ;-) You can
pick voice information out of an incredible amount of noise!

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
 
R

Rich Grise

Jan 1, 1970
0
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.

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:
http://www.neodruid.org/images/NiMH-Charger.jpg

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
 
I

Ian Stirling

Jan 1, 1970
0
Years ago, I heard a demo of the human voice with 1-bit resolution. It
was understandable, but not at all pleasant.

I've clocked high-pass (300Hz) signals through a 3Khz flip-flop.
Surprisingly good, using a speech radio station as a signal source.
 
R

Richard Crowley

Jan 1, 1970
0
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.

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.
 
J

John Larkin

Jan 1, 1970
0
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.

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
 
K

keith

Jan 1, 1970
0
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.

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.
 
K

keith

Jan 1, 1970
0
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."

....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.
 
I

Ian Stirling

Jan 1, 1970
0
In sci.electronics.design keith said:
What amazes me is the cost of text-messaging. Why do I want to do that
again?
Time?

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.

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/...
 
K

keith

Jan 1, 1970
0

Typing a text-message in on my phone is going to save me time? OTOH,
their time is certainly cheaper.
If you feel comfortable talking to people by just reciting a message,
then you can probably get it done faster/cheaper.
Huh?

But, how often is that the case?
Many people on the other end will digress into weather/how their dog is/...

Huh^2?
 
M

Mr.T

Jan 1, 1970
0
Does it? I'm interested in your calculations.
There should be a market then for someone to simply put the exact same
technology into a 9V pack.
I think it

It's even easier now with DC-DC switching converters.
Hasn't someone already mentioned the 6X AAA pack? Only a few mm bigger
than a 9V,

Wow, either your AAA are smaller than ours, or your talking about bigger 9V
batteries than I am.
Including a cell holder makes our 6*AAA packs over twice as big as a single
9V battery with snap.
Even without a cell holder they still have quite a bit more volume.

MrT.
 
K

Ken Smith

Jan 1, 1970
0
Does it? I'm interested in your calculations.
There should be a market then for someone to simply put the exact same
technology into a 9V pack.

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.
 
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