Driver to drive?

[Cursitor Doom]

On Sat, 18 Mar 2017 13:23:29 -0700, tabbypurr wrote:

On Saturday, 18 March 2017 19:12:10 UTC, Cursitor Doom wrote:
On Sat, 18 Mar 2017 10:04:38 -0700, tabbypurr wrote:

the problem of course is wrong convictions.

Indeed. So introduce a higher standard of proof in capital cases:
'beyond doubt' instead of 'beyond reasonable doubt.'

You can introduce all the requirements you like, it doesn't stop people
being stupid.

Under the guidance of a competent and serious-minded judge, the
application of a higher standard of proof such as that suggested should
be pretty straightforward for even the meanest and basest of juries to
understand.

 

On Saturday, 18 March 2017 22:59:39 UTC, Cursitor Doom wrote:

On Sat, 18 Mar 2017 13:23:29 -0700, tabbypurr wrote:
On Saturday, 18 March 2017 19:12:10 UTC, Cursitor Doom wrote:
On Sat, 18 Mar 2017 10:04:38 -0700, tabbypurr wrote:

the problem of course is wrong convictions.

Indeed. So introduce a higher standard of proof in capital cases:
'beyond doubt' instead of 'beyond reasonable doubt.'

You can introduce all the requirements you like, it doesn't stop people
being stupid.

Under the guidance of a competent and serious-minded judge, the

something that does not always occur

application of a higher standard of proof such as that suggested should
be pretty straightforward for even the meanest and basest of juries to
understand.

And yet it fails anyway. The ways in which people come to believe nonfacts are legion.


NT

 

[John Larkin]

On Sat, 18 Mar 2017 12:49:48 -0700 (PDT), mkolber1@gmail.com wrote:

So the next topic is to compare and contrast the merits
of an H field sensing loop antenna vs an E Field sensing
whip antenna for use on the AM broadcast band.
In practice, most car radios use an E Field whip
and most other radios use an H field loop.
How do they compare?
M

Wild guess: indoors, there is a lot of e-field noise. Outdoors, not so
much.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[bitrex]

On 03/17/2017 03:25 PM, John Larkin wrote:

On Fri, 17 Mar 2017 12:29:05 -0400, bitrex
bitrex@de.lete.earthlink.net> wrote:

On 03/16/2017 08:36 PM, Phil Allison wrote:
George Herold wrote:



I've got an AM radio that came with an air core antenna.
(1990's vintage)
~4" (10 cm) squarish loop. Not sure how many turns.
Works fine.


** So it's an external loop for a main powered receiver ?

Right, It's a JVC "ultra compact component system"
FS-1000


** So why didn't you post that info before?

It's a fucking frame antenna, already discussed here in this thread and been around since the dawn of radio.



Knowing almost nothing about AM, (and assuming I don't care about price.)
I figure I want the highest Q possible on the front end..


** Nope.

You need at least 10kHz of bandwidth at the antenna so the Q must not exceed 50 to 100 across the AM band. You will find that antenna has a fairly low Q in practice.



You need to learn how to post unambiguously too.

IOW not smartarse style like Larkin.

Larkin is great,

** Larkin is a smug pig and a troll.

He is so narcissistic he thinks he owns the NG and everyone on it.

To be fair he probably knows that Usenet was designed to not have a
central administrator...

There are moderated NGs. This ain't one.

Most of usenet is dead. SED is unusually active, some of it actually
on topic.

Probably for the best; thinking back about the mid 1990s and looking
through the list of dead "alt" newsgroups you wonder "what the hell were
they thinking?"

Not sure anyone is missing the loss of alt.sex.animals.monica-lewinsky
or alt.flame.jews in Web 2.0 2k17

 

On Sunday, March 19, 2017 at 11:05:50 AM UTC+11, k...@notreal.com wrote:

On Sat, 18 Mar 2017 19:05:50 -0000 (UTC), Cursitor Doom
curd@notformail.com> wrote:

On Sat, 18 Mar 2017 12:54:27 -0400, bitrex wrote:

I'm a liberal and yet, in some circumstances I do support the death
penalty.

But IMO the goal should be to show the condemned the mercy they did not
show their victim(s) in life.

And you imagine they'd a) appreciate that gesture and b) learn from it?

You don't want them to learn from it. Too late.

As civilized people it's the least we could do.

Each case on its merits, dear boy; each case on its merits.

I'm with Shortrex on this one. Just off them and be done with it. It
shouldn't even be advertised in advance. Just do it.

Krw's infallible imagination makes him over-confident. Execution is irrevocable.

--
Bill Sloman, Sydney

 

On Sunday, 19 March 2017 00:51:19 UTC, rickman wrote:

I'm not sure it is very
relevant that someone could be found innocent after spending 20 years in
prison if that is such a heinous punishment.

Why don't you ask the people released after 20 years whether it's relevant.


NT

 

Siemens BB112
http://pdf1.alldatasheet.com/datasheet-pdf/view/44230/SIEMENS/BB112/+3_342UOGDL.OudGhtNz+/datasheet.pdf

Toshiba 1SV149
http://pdf1.alldatasheet.com/datasheet-pdf/view/29858/TOSHIBA/1SV149/+QJJ59UPLRhpDDdAXbNwH+/datasheet.pdf

Yeah, I know they used to exist. I still have some MVAM109s in my drawer. I was asking about current production though.

Cheers

Phil "BB209 fan" Hobbs

 

On Sat, 18 Mar 2017 12:57:19 -0700, John Larkin
<jjlarkin@highlandtechnology.com> wrote:

On Sat, 18 Mar 2017 12:49:48 -0700 (PDT), mkolber1@gmail.com wrote:

So the next topic is to compare and contrast the merits
of an H field sensing loop antenna vs an E Field sensing
whip antenna for use on the AM broadcast band.
In practice, most car radios use an E Field whip
and most other radios use an H field loop.
How do they compare?
M

Wild guess: indoors, there is a lot of e-field noise. Outdoors, not so
much.

In the far field (radio station), both the E and H fields are
inversely proportional to the distance (and hence power density
proportional to the inverse square of distance). In this area the free
space impedance (relation between E and H) is 120 pi or 377 ohms.

In the near field (local noise), the H-field drops faster than the
E-field with distance, thus a better SNR can be obtained with
H-antenna in the near field of a noise source.

One can argue where is the border line between near and far field, but
at least 0.1 wavelenghts is definitively near field, i.e for 1 MHz at
30 m. In a residential area, there are a lot of noise sources within
that range. In a car on a highway, there are only a few noise sources
constantly within that distance, as long as you have suppressed any
noise sources from your own car.

 

I've used them in instruments but never in receivers. Gilbert cells are _not_ strong mixers
--they have many fine qualities, but good IMD performance is not one of
them.

Interesting. Please educate me - when you say "strong" do you mean
"involving sharp switching"? Is is Miller effect and LO feedthrough
that limits the "strength"? Does HFA3101 not qualify as "strong"?

A strong mixer is one with really good IMD performance. Antennas pick up everything at some level, so the amount of stuff that your poor little RX front end has to cope with is pretty appalling.

A diode bridge with 2 or 3 series-connected Schottky diodes in each arm and a +17 dBm LO is one decent approach, and you can get one from Mini Circuits in one day if you like.

A bridge made from a fast CMOS mux is another good approach, though it takes more manual work.

These techniques use square wave switching (or nearly), which greatly reduces the proportion of the time when the switching devices are in their 'linear' range.

In order to make an order-1 change in the behaviour of a Level 17 mixer or a FET MUX, an interfering signal has to be pretty big, i.e. a volt or two.

To do the same to a Gilbert cell requires about e/kT, i.e. ~26 mV. So on a simplistic analysis, a Gilbert cell becomes nonlinear at levels a good 40 dB lower than a strong mixer.

Cheers

Phil Hobbs

 

On Sat, 18 Mar 2017 14:47:24 -0700 (PDT), pcdhobbs@gmail.com wrote:

On the other hand, one could just use a Mini Circuits mixer with a +17
dBm LO, or a nice analogue mux with square wave drive.  It takes a lot
to screw one of those up.

The SA612 gives you oscillator and 14dB gain mixer in an 8-pin package,
for a buck. Good to 200MHz LO.

I've used them in instruments but never in receivers. Gilbert cells are _not_ strong mixers--they have many fine qualities, but good IMD performance is not one of them.

Completely agree.

I had a VLF/LF/MF upconverter using such chips. With a random wire in
the apple trees as antenna directly connected to the mixer, the
usability was bad due to a broadcast station at 30 km distance.

With a tunable preselector, all those problems went away and the
preselector presented a better match between the highly capacitive
antenna and the mixer input. I could hear time stations with good SNR
at 2000 km distance even during the day, while "atomic" clocks could
synchronize only during the short night hours using the internal
ferrite antenna.

 

[Kevin Aylward]

"bitrex" wrote in message news:9DdzA.62942$mb5.42260@fx19.iad...

I'm a liberal and yet, in some circumstances I do support the death
penalty.

I am 100% against state executions, for several reasons.

One is that it is absolutely *impossible* to prove guilt to 100%.

http://www.deathpenaltyinfo.org/innocence-list-those-freed-death-row

Anyone that believes that one innocent man executed is acceptable collateral
damage in the criminal justice system should re-evaluate their moral
compass, and whether they 100% value the life of their innocent children.

The state should never have the power to execute people, I will leave that
one for now, as the above, is enough.


-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html

 

[David Eather]

On Sun, 19 Mar 2017 09:39:11 +1000, David Eather <eather@tpg.com.au> wrote:

https://twitter.com/RonWyden/status/832985891186487296/video/1

--
Using Opera's mail client: http://www.opera.com/mail/

 

On Sat, 18 Mar 2017 16:04:00 -0000 (UTC), Cursitor Doom
<curd@notformail.com> wrote:

On Sat, 18 Mar 2017 10:50:10 -0400, krw wrote:

http://www.roadsideamerica.com/story/7814

In your case, I'd pay gladly for the electricity.

Always struck me as a bit OTT and perhaps unnecessarily so. It only takes
a fraction of the energy 'Old Sparky' dished out to kill someone. Atrial
Fibrillation can be induced with just a few tens of milliamps. OK, I'll
grant you it's far less spectacular than this:

The point is not to put the perp in (ventrical [*]) fibrillation,
rather to stop the heart parmanently.

[*] Atrial fibrillation isn't all that dangerous, in itself.

https://www.youtube.com/watch?v=WCJUEvFYaGc

But there you go. That's entertainment!

Looks like Blobby.

 

On Sat, 18 Mar 2017 19:09:14 -0000 (UTC), Cursitor Doom
<curd@notformail.com> wrote:

On Sat, 18 Mar 2017 10:04:38 -0700, tabbypurr wrote:

the problem of course is wrong convictions.

Indeed. So introduce a higher standard of proof in capital cases: 'beyond
doubt' instead of 'beyond reasonable doubt.'

That's impossible, which is the whole "reasonable" thing.

 

On Sat, 18 Mar 2017 19:05:50 -0000 (UTC), Cursitor Doom
<curd@notformail.com> wrote:

On Sat, 18 Mar 2017 12:54:27 -0400, bitrex wrote:

I'm a liberal and yet, in some circumstances I do support the death
penalty.

But IMO the goal should be to show the condemned the mercy they did not
show their victim(s) in life.

And you imagine they'd a) appreciate that gesture and b) learn from it?

You don't want them to learn from it. Too late.

As civilized people it's the least we could do.

Each case on its merits, dear boy; each case on its merits.

I'm with Shortrex on this one. Just off them and be done with it. It
shouldn't even be advertised in advance. Just do it.

 

On Sat, 18 Mar 2017 23:48:40 +0200, upsidedown@downunder.com wrote:

On Sat, 18 Mar 2017 12:57:19 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:

On Sat, 18 Mar 2017 12:49:48 -0700 (PDT), mkolber1@gmail.com wrote:

So the next topic is to compare and contrast the merits
of an H field sensing loop antenna vs an E Field sensing
whip antenna for use on the AM broadcast band.
In practice, most car radios use an E Field whip
and most other radios use an H field loop.
How do they compare?
M

Wild guess: indoors, there is a lot of e-field noise. Outdoors, not so
much.

In the far field (radio station), both the E and H fields are
inversely proportional to the distance (and hence power density
proportional to the inverse square of distance). In this area the free
space impedance (relation between E and H) is 120 pi or 377 ohms.

In the near field (local noise), the H-field drops faster than the
E-field with distance, thus a better SNR can be obtained with
H-antenna in the near field of a noise source.

One can argue where is the border line between near and far field, but
at least 0.1 wavelenghts is definitively near field, i.e for 1 MHz at
30 m. In a residential area, there are a lot of noise sources within
that range. In a car on a highway, there are only a few noise sources
constantly within that distance, as long as you have suppressed any
noise sources from your own car.

I've always used the definition of near/far as whether the source can
be resolved or whether it's a point source. IOW, if the source has a
"visible" area, it's near field.

 

[rickman]

On 3/18/2017 5:53 PM, pcdhobbs@gmail.com wrote:

Try 500+ pF. They make varactors specifically to tune AM radios. I
just ordered a few.

Current production? Who makes them?

Cheers

Phil Hobbs

http://www.nteinc.com/diodes/varactors.php?a=12

http://dilp.netcomponents.com/cgi-bin/nteinc.asp?partnumber1=NTE618

--

Rick C

 

[rickman]

On 3/18/2017 7:13 PM, Kevin Aylward wrote:

"bitrex" wrote in message news:9DdzA.62942$mb5.42260@fx19.iad...


I'm a liberal and yet, in some circumstances I do support the death
penalty.

I am 100% against state executions, for several reasons.

One is that it is absolutely *impossible* to prove guilt to 100%.

http://www.deathpenaltyinfo.org/innocence-list-those-freed-death-row

Anyone that believes that one innocent man executed is acceptable
collateral damage in the criminal justice system should re-evaluate
their moral compass, and whether they 100% value the life of their
innocent children.

The state should never have the power to execute people, I will leave
that one for now, as the above, is enough.

Someone else expressed the opinion that death was more merciful than
life in prison. So is it better to give an innocent person life in
prison? Very few lifers are ever acquitted. I'm not sure it is very
relevant that someone could be found innocent after spending 20 years in
prison if that is such a heinous punishment.

--

Rick C

 

[Jeff Liebermann]

On Sat, 18 Mar 2017 20:38:01 -0400, rickman <gnuarm@gmail.com> wrote:

On 3/18/2017 5:53 PM, pcdhobbs@gmail.com wrote:
Try 500+ pF. They make varactors specifically to tune AM radios. I
just ordered a few.

Current production? Who makes them?
Cheers
Phil Hobbs

http://www.nteinc.com/diodes/varactors.php?a=12
http://dilp.netcomponents.com/cgi-bin/nteinc.asp?partnumber1=NTE618

Siemens BB112
<http://pdf1.alldatasheet.com/datasheet-pdf/view/44230/SIEMENS/BB112/+3_342UOGDL.OudGhtNz+/datasheet.pdf>

Toshiba 1SV149
<http://pdf1.alldatasheet.com/datasheet-pdf/view/29858/TOSHIBA/1SV149/+QJJ59UPLRhpDDdAXbNwH+/datasheet.pdf>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Clifford Heath]

On 18/03/17 13:31, rickman wrote:

On 3/17/2017 8:10 PM, John Larkin wrote:
On Sat, 18 Mar 2017 10:32:58 +1100, Clifford Heath
no.spam@please.net> wrote:

On 18/03/17 06:21, John Larkin wrote:
Resonating an AM antenna needs a giant variable cap, or a varicap and
some sort of tracking voltage source for that.

They don't make big enough varicaps for that, but those Superjunction
FETs discussed here recently would work.

A friend designed a specialised hand-held pickup head that had
to tune 1-5MHz, and used 480(!) small varicaps. It was measuring
micro-ohms of dynamic impedance using transformer coupling
(about 8mm square) across a small air gap. The DUT had dozens
of resonances with Q of 1000-5000 across the band.

I suggested using the Superjunction FETs, but the device is finished.

Clifford Heath.

You can get varicaps up to about 100 pF. To resonate in the AM band,
having a ferrite core would help get enough inductance.

Try 500+ pF. They make varactors specifically to tune AM radios. I
just ordered a few.

Bit difficult to use FET switching with those to make a 25:1
capacitance ratio however.

It seems that my friend could have used 10x switched capacitors
and just a few varactors for fine tuning, but I never saw the
design parameters. Even the Litz wire pickup coil took a large
design effort.