RF through water question

I just picked up this one, having read "blind man's bluff" recently.

The chapter on "Hunt for Red October" was rather chilling, as I was living in Hawaii at the time.

Black produces much better results

Regards,

Boris Mohar

Got Knock? - see: Viatrack Printed Circuit Designs

Ha, ha, water skiing seagulls.Couldn't they put weights on it to hold it below the surface.

You can turn it off on your reciever. Mine is always off.

Not to mention a powerful spamfilter.

- YD.

in article snipped-for-privacy@4ax.com, Boris Mohar at borism_-void- snipped-for-privacy@sympatico.ca wrote on 5/12/04 6:50 PM:

This use of a marker is a new one for me, but makes reasonable sense. The use of the green marker that was publicized over five years ago was to improve the fidelity over that of the digital sound as extracted from the unmarked CD. That is what I consider to be koo-koo.

Bill

I thought it was green marker around the outside edge. No wonder it didn't work.

its not about sanity; it's about happiness.

Sorry!!! Just started using a new/different news client. ARM

On Tue, 11 May 2004 10:59:28 -0500, "Ron H." Gave us:

It will act as a resistor. At low power, perhaps a bit different. At high power, it is a bulk resistor. The dimensions of the cavity would help.

On Tue, 11 May 2004 14:29:31 -0500, snipped-for-privacy@usa.net Gave us:

It is a series element, not a shunt to ground. It will act as a resistor.

On Tue, 11 May 2004 23:34:01 -0700, "Max Hauser" Gave us:

Is this why QAM 256 is far better than simple modulation schemes?

I mean it allows for so much more *use* of the signal as it is being sent.

Anyway, this is party why one can get so many more channels per transponder on a comm bird than was available in the past. That 6MHz wide channel is being filled to the brim with data (and that data compressed as well), as opposed to the signals they repeated in the

60s and 70s.

Thank God for General Instrument (now a division of Motorola).

They (along with others) brought you wide screen form factors, MPEG-2, and HDTV. As well as twelve channel per carrier uplink encoding and decoding. They made your Video/TV life over ten times richer.

GI was not just another cable box maker.

Then the Cable Cos ream us up the ass with their pricing. All the while letting their hardware age, and fester, instead of keeping up. They call that "a good value service".

Cox's news server is one fine example. I'd be surprised if it is even one terabyte in archive size.

On Wed, 12 May 2004 07:47:15 GMT, Repeating Rifle Gave us:

Let's just say that you have your eccentricities too.

For a litz wire to give an advantage that is indeed audibly notable, the base system needs to start at around $40k. Some dipshit's $5k or

10k "stereo" ain't gonna get it, and the $20k jobs can barely make the difference any greater than negligible. It takes a truly knowledgable person to quell acoustic demons at this level.

However, on said $40k system, the differences indeed do show themselves, and make such purchases viable for such systems.

For Joe Blow's shitbox, however, they are a laugh. Monster laughs all the way to the bank.

Tube amps have advantages for live performers, such as a bassist.

Since the days of FET driven, and module driven amplifiers, however, even those guys would have a hard time telling the difference without introducing high slew rate transients at the pickups in order to "tell" what is driving the acoustic transducers (speakers). Those amps have their place though.

Acoustics plays into electronics more than one may think.

Take HF cores and magnetics. Why do they sing when they are not varnish impregnated? What do you think magnetostriction is? It is a mechanical action, and therefore will have acoustical resonances and interplay. A flyback uses magnetic core saturation as the resonant function for making an oscillation. Placing a clamp on an E core will at some point of increased pressure, restrict it's flux flow, and will be exhibited as heat, and electrical losses. At normal pressures, it minimizes air gap, and maximizes efficiency in cases where the gap is not an element of the circuit function, just transformer efficiency.

Other HF transformers have operation which IS gap dependant, such as PWM driven units which cause drivers to ring or clip if the gap is too small, and are too lossy if it gets too big.

At human audible frequencies copper wire has no notable skin effect, and skin effect itself is an effect of the e-field pushing the electrons to the outside of the conductor, not any kind of acoustic demon.

When there is a lot of time (long period), a lot (thickness) of electrons flow near the surface. When the period is less, the same number of electrons flow (for a given amperage) in a thickness (skin) that is much closer to the surface of the conductor. So, the faster the AC frequency, the lower the cross sectional thickness of a given conductor gets used. This is why litz works so well at high frequencies. All those presumably small "skins" add up to way more cross sectional thickness for the purpose of actual flow than does a single strand that matches the thickness of the entire litz bundle.

On Wed, 12 May 2004 21:50:20 -0400, Boris Mohar Gave us:

That's not what the green MM's function was purported to be.

It was supposed to make it sound better.

It was NOT about copy protected discs.

It was, and is BULLSHIT. Laser read head assemblies pick up directly reflected "lands". That is the opposite of "pits", and is quite bright bouncing back into the pickup for a "one" binary read.

The "pits", and all other extraneous reflections, such as the friggin' scatter that is claimed to be reduced or negated by this green Magic Marker technique, does NOT get read at all, so it is, and has always been bullshit.

On Thu, 13 May 2004 06:17:53 GMT, Repeating Rifle Gave us:

It is.

On Wed, 12 May 2004 23:43:06 -0700, "Richard Henry" Gave us:

It was. It didn't work, because it DOESN'T work.

I thought they became microchip?

On Thu, 13 May 2004 23:15:17 -0500, "Dave VanHorn" Gave us:

Motorola only bought the uplink encoder division from what I know... which is not exactly what happened... :]

GI has been around for decades, they bought the encoder division which was formerly an arm of Titan/ Linkabit. Or was them.

Anyway... thank them and Woo Paik in particular (now in S. Korea as Pres of his own company) specifically for HDTV in digital form. Were it not for them, the idiots in the consortium would have made an analog version... Oh boy.

That would kind of defeat the purpose of having a 'floating wire' now wouldn't it? The whole idea was to have the black 'wire' float along the surface and receive incoming transmissions without the submarine having to surface. Sinking the wire would make it harder to receive RF.

daestrom