magnetic field

[John Larkin]

On Thu, 28 Oct 2004 23:53:50 GMT, Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hi John,

Is there a place in modern technique for regeneration (Q-multiplication)?



Rarely, if ever. Gain and selectivity are cheap nowadays, and
regeneration trades them for stability.


So after trying to mimick tube amps via algorithms the next big thing
would be the emulation of a Q multiplier on a DSP

IIR filter.

John

 

[john jardine]

"Alan Horowitz" <alanh_27@yahoo.com> wrote in message
news:1e3670a7.0410281434.70887cc7@posting.google.com...

Is there a place in modern technique for regeneration (Q-multiplication)?

Yes, course there is.
Needed a 300Hz bp filter for an I.F stage. too wide for a crystal, too
narrow for a tuned circuit. Ended up using a Twin-T with feedback to give Q
enhancement and flat response.
regards
john

 

[Ken Smith]

In article <1e3670a7.0410281434.70887cc7@posting.google.com>,
Alan Horowitz <alanh_27@yahoo.com> wrote:

Is there a place in modern technique for regeneration (Q-multiplication)?

Most RC+opamp filters include some sort of positive feedback.

--
--
kensmith@rahul.net forging knowledge

 

[Brian Reay]

"Alan Horowitz" <alanh_27@yahoo.com> wrote in message
news:1e3670a7.0410281434.70887cc7@posting.google.com...

Is there a place in modern technique for regeneration (Q-multiplication)?

Yes, if that is the optimal way to meet the requirement. However, I'd have
thought a DSP based solution would be more likely.

--
Brian Reay
www.g8osn.org.uk
www.amateurradiotraining.org.uk
FP#898

 

[exxos]

"Karl-Hugo Weesberg" <netspider4@lycos.com> wrote in message
news:7666ed5f.0410281959.18542571@posting.google.com...

I need to build it to escape this boring planet before I die of boredom.

So what do I need for a trans-dimensional gateway?

LOTS of power, and maybe it will have a BC548 in it somewhere.....

Chris

 

[Bob Masta]

On 28 Oct 2004 15:34:27 -0700, alanh_27@yahoo.com (Alan Horowitz)
wrote:

Is there a place in modern technique for regeneration (Q-multiplication)?

Not exactly what you asked for, but you might be interested to know
that this is exactly what is going on in your inner ear... and it's
partly mechanical! The sensory cells in your cochlea sit on the
basilar membrane, which vibrates from the incoming sound.
The sound enters at one end of the cochlea, where the
basilar membrane is narrow, stiff, and has low mass. The
membrane becomes wider, more massive, and less stiff as
you go toward the apex of the cochlea. The incoming sound
generates a travelling wave on the membrane, with a peak
at a frequency-specific location.

But it wouldn't be very sharply tuned just from the mechanics.
As it turns out, there are 2 different kinds of sensory cells
on the basilar membrane: one row of Inner Hair Cells which
actually tranduce the sound into neural signals to the brain,
and 3 rows of Outer Hair Cells which are electromechanical
amplifiers. They change length according to the voltage
across them, and they also change the flow of current and
hence the voltage across themselves when this happens.
The net effect is that they form a regenerative amplifier
that provides a huge Q-multiplication for the mechanical
tuning of the basilar membrane, and it is this enhanced
vibration that excites the Inner Hair Cells to give enhanced
sensitivity to low sound levels. Without this effect we'd
lose about 60 dB of sensitivity at low sound levels.
(The effect saturates at higher levels.)

Just thought you'd like to know!


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

 

[CWatters]

"Tel boy" <tel1e@hotmail.com> wrote in message
news:4cb92906.0410290259.1e935df0@posting.google.com...

I have a 6amp 12-volt battery charger for charging my car battery, no
problems here! However I also have a motorcycle that has one of those
sealed batterys, now from what I have read I believe that you are not
supposed to charge this type of battery with a normal charger, as it will
damage the battery somehow. Is this correct?

There are different types of sealed battery. Check with the manufacturer of
the battery as it's probably ok.

Most lead acid batteries use a standard constant voltage charge profile but
the recommended float voltage can sometimes vary slightly from make to make.

 

[CWatters]

"Karl-Hugo Weesberg" <netspider4@lycos.com> wrote in message
news:7666ed5f.0410281959.18542571@posting.google.com...

I need to build it to escape this boring planet before I die of boredom.

So what do I need for a trans-dimensional gateway?

Two worm holes and a lot of energy.

 

[Boris Mohar]

On Fri, 29 Oct 2004 18:59:14 GMT, "CWatters" <colin.watters@pandoraBOX.be>
wrote:

"Karl-Hugo Weesberg" <netspider4@lycos.com> wrote in message
news:7666ed5f.0410281959.18542571@posting.google.com...
I need to build it to escape this boring planet before I die of boredom.

So what do I need for a trans-dimensional gateway?

Two worm holes and a lot of energy.

Must rub two trolls together first.

This idiot without imagination has been posing these kinds of witless
idioticies under different aliases all over the usenet. Ok, maybe he is not
an idiot maybe he is just a nine year old.

--

Boris Mohar

 

[Volund]

"exxos" <exxos@home.co.uk> wrote in message
news:418224ad$0$16437$cc9e4d1f@news-text.dial.pipex.com...

"Karl-Hugo Weesberg" <netspider4@lycos.com> wrote in message
news:7666ed5f.0410281959.18542571@posting.google.com...
I need to build it to escape this boring planet before I die of boredom.

So what do I need for a trans-dimensional gateway?

LOTS of power, and maybe it will have a BC548 in it somewhere.....

A LONG AC cord too, one of those curly ones..................

 

[clifto]

Bob Masta wrote:

Just thought you'd like to know!

If only you could explain cochlear hydrops in a way that suggested a fix.

--
So those 380 tons of missing explosives were moved by Saddam before all
those expert inspectors noticed, eh?

No wonder twelve years of inspections found NOTHING.

 

[Steve Nosko]

"Ken Smith" <kensmith@green.rahul.net> wrote in message
news:cls6o5$urr$2@blue.rahul.net...

In article <1e3670a7.0410281434.70887cc7@posting.google.com>,
Alan Horowitz <alanh_27@yahoo.com> wrote:
Is there a place in modern technique for regeneration (Q-multiplication)?

Most RC+opamp filters include some sort of positive feedback.

Umm. Er Don't you mean negative?

Steve, K9DCI.

 

[John Larkin]

On Fri, 29 Oct 2004 21:06:01 GMT, Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hi Alan,

Selectivity at the upper decades of Mhz is cheap nowadays? Where do I
buy one of these flea-market tuneable multi-ganged, several-octave
HF-VHF preselectors?


Only using conversion - filter - conversion back. Otherwise it's cavity
resonators and beaucoup Dollars.

Or SAWs, or ceramic resonators, or DSP stuff.

John

 

[exxos]

"Boris Mohar" <borism_-void-_@sympatico.ca> wrote in message
news:7s65o0pu9kbs472tp7gvfha64cq0mk73uu@4ax.com...

On Fri, 29 Oct 2004 18:59:14 GMT, "CWatters" <colin.watters@pandoraBOX.be
wrote:


"Karl-Hugo Weesberg" <netspider4@lycos.com> wrote in message
news:7666ed5f.0410281959.18542571@posting.google.com...
I need to build it to escape this boring planet before I die of boredom.

So what do I need for a trans-dimensional gateway?

Two worm holes and a lot of energy.


Must rub two trolls together first.

This idiot without imagination has been posing these kinds of witless
idioticies under different aliases all over the usenet. Ok, maybe he is
not
an idiot maybe he is just a nine year old.

aka - a idiot ;-)

Chris

--

Boris Mohar

 

[John Fields]

On 28 Oct 2004 20:59:47 -0700, netspider4@lycos.com (Karl-Hugo
Weesberg) wrote:

I need to build it to escape this boring planet before I die of boredom.

So what do I need for a trans-dimensional gateway?

---
A short piece of pipe with an 0.22" diameter bore, a 22 caliber
long rifle rim-fire cartridge and a hammer.

--
John Fields

 

[John Larkin]

On Sat, 30 Oct 2004 03:13:04 +0000 (UTC), kensmith@green.rahul.net
(Ken Smith) wrote:

In article <bzzgd.2281$zx1.304@newssvr13.news.prodigy.com>,
Joerg <notthisjoergsch@removethispacbell.net> wrote:
[...]
Direct DSP would be prohibitively expensive at VHF. Probably you'd have
to assemble an array the size of a large pizza and call the power
company before turning it on.

Thats the easy part. First, you have to run the signal through an ADC.
Doing an ADC that has very many bits is tricky at high frequencies. You
would end up with a combination ADC and spaceheater.

12 or 14 bit, 80 MSPS ADCs are cheap and plentiful nowadays, and
consume a few hundred milliwatts.

John

 

[John Larkin]

On Sat, 30 Oct 2004 03:40:44 +0000 (UTC), kensmith@green.rahul.net
(Ken Smith) wrote:

An engineer I know attempted a design like that and found that (A) 14 bits
isn't enough and (B) 50 MSPS (his case) isn't enough either. Unless you
put an analog filter infront of the ADC, a strong station dominates and
the performance just isn't there.

Well, sure, but it's probably not going to be a regenerative amp
stage.

John

 

[Sad]

"CWatters" <colin.watters@pandoraBOX.be> wrote in news:6qwgd.3799$wt.366625
@phobos.telenet-ops.be:

"Karl-Hugo Weesberg" <netspider4@lycos.com> wrote in message
news:7666ed5f.0410281959.18542571@posting.google.com...
I need to build it to escape this boring planet before I die of boredom.

So what do I need for a trans-dimensional gateway?

Two worm holes and a lot of energy.

I can do it with one worm hole and relatively small amount of anti-energy.

 

[Ken Smith]

In article <dr36o0pq3bvcvo3qr47v6iq1gfdbgsaf1a@4ax.com>,
John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote:

On Sat, 30 Oct 2004 03:40:44 +0000 (UTC), kensmith@green.rahul.net
(Ken Smith) wrote:


An engineer I know attempted a design like that and found that (A) 14 bits
isn't enough and (B) 50 MSPS (his case) isn't enough either. Unless you
put an analog filter infront of the ADC, a strong station dominates and
the performance just isn't there.


Well, sure, but it's probably not going to be a regenerative amp
stage.

No, he ended up doing an analog superhet. down to an IF he then digitized.
The circuit was working great on the day the project was cancelled. It
was great electronics attempting to implement something the physics said
wouldn't work. He knew the idea was daft but he needed the work and they
wouldn't listen to him.

--
--
kensmith@rahul.net forging knowledge

 

[Joel Kolstad]

"Ken Smith" <kensmith@green.rahul.net> wrote in message
news:clv56c$bav$2@blue.rahul.net...

The circuit was working great on the day the project was cancelled. It
was great electronics attempting to implement something the physics said
wouldn't work.

Sounds much more likely he was attempting to implement something the boss
said wouldn't work.