Specifically Designed For Oscar Moon Bounce Degrees Elevation

425 Highland Parkway, Norman, Oklahoma 73069 Oklahoma Residents Call (405) 360 6410

v* R&adet Service^see page 179

Seventy three, March 1980 43

Irving M Gottiieb W6HDM 931 Olive Street Menio Park CA 94025

Future Rig and Rigamarole

— are you ready for faster-than-light propagation?

In buoyant spirits the other evening, 1 devoted my efforts to the noble task of extracting a couple of extra functions from one of the dedicated ICs in my all-silicon rig Dedication notwithstanding, the sophisticated chip made several futile attempts to comply with my desires, then bit the dust without the glowing anode, hot smell, or audible stress signals which have reliably guided my experimental endeavors throughout a!l these many years of hamming. Well, so be it! Never had I been one to remain idle very long when aflame with the passion to experiment.

1 quickly transferred my creative urges to some experiments in high technology I had long intended to perform. Gathering together a couple of servicemen's signal generators, my ancient-vintage oscilloscope, and a handful of junk box components, I was off to the races.

Soon I was observing endless variety in the display of all manner of geometric patterns. These danced across the 'scope screen in almost hypnotic gyrations, and my main task was to hold some of them sufficiently steady for evaluation. Call such activities merely eiec-tronic doodling if you wish, OM, but please be assured that I was never one to use the meager time allotted to us in frivolous fashion. Indeed, the phosphor's ^reen glow harmonized appropriately with the greenbacks I envisaged some large firm would fork over for exclusive rights to a rapid method for generating artistic designs for neckties, wallpaper, and for improving the esthetics of the environment in general. (In lieu of your initial reaction, OM, I trust a more considered judgment will recognize the goal-motivated nature oi this research project.)

One thing leading to another, it happened that I accidentally, or synergisti-catly, injected into a diode circuit a signal of several kHz together with one of several tens-of-kHz, whereupon 1 monitored a fairly nice amplitude-modulated waveform,, However, because of the inadequacies of the scope sync system, and surely because of the haywire aspect of my lash-

up, 1 couldn't quite stop the display. The modulation drifted slowly from left to right across the screen and the carrier cycles contained therein drifted in the same direction, but at a livelier rate This provided the illusion that the carrier eye les were "walking through'' the modulation envelope (sen Fig, 1), If, OM, you now agree that one Ihing is going to lead to another, your intuition is right on the beam!

As if in a trance, I felt this fascinating display eradicate my fantasies of millions of polyester shirts bearing frozen I issajous patterns at a penny royalty for each Rather i began to think of my pattern generator as a tutorial aid to technical instruction courses! Here, for example, was an excellent depiction of the concepts of group-velocity and phasevelocity in the propagation of radio waves; even though the carrier waves were zipping along at their own merry pace (phase-velocity), they did not determine the rate at which the information in the modulation envelope was irans-

Fig. /. The unexpected scope display —a good graphic s/mu/afion of group- and phase-velocity. When the phasevelocity of the carrier cycles exceeds the speed of radiation in free spacey the carrier will "walk through " the modulation envelope. The modulating information, therefore, can progress only at the slower group-velocity. (In free space, the phase- and group-velocities are fhe sa me J

Fig. 2. DX via skip involves wave speeds greater than the speed of light in free space, (A) The speed of propagation does not exceed c, the speed of light in free space. (B) Top portions of wave fronts exceed c, thereby causing bending of the propagation path, (C) Once out of the ionosphere, the situation is again as in Region A.

ferred "from transmitter to receiver/' i.e., from the left to the right side of the oscilloscope screen.

This phenomenon is particularly interesting because phase-velocity can exceed the value of c, the speed of light in free space! And fcinstein's postulates are not violated, we are told, inasmuch as phase-velocity in excess of c cannot carry matter, energy, or information with it, In a sense, phase-velocity is a mathematical abstraction; it is not directly detectable by any device or circuit, It is a tantalizing notion, however, that a school of thought proclaims the possibility that matter and information can have super-c speeds If so, its speculations allow for speeds from c to infinity, but not at c We are reminded of supersonic aircraft—once ha\ing penetrated the sonic barrier, their speeds are no longer limited by the speed of sound.

In another sense, this faster-than-Iight entity, phase-velocity, serves various mundane purposes Whenever light travels from one medium to another, we find that its action is precisely described by considering not one, but two, speed components—group- and phasevelocity More relevant to the antics of hams, DX communication by means of skip is a ta^e in point. In Fig 2 we see a long-distance QSO that obviously is based neither on ground waves nor on line-of-sight. Rather, the radio waves enter the ionosphere, are refracted therein, and return to a distant QTH. Refraction is but another term for bending — why is the path of the waves bent? The ionosphere is a transmission medium containing free electrons of increasing density as the radio waves enter it. An energy interaction occurs, and the top portion of the wave fronts is speeded up reiative to the lower portions. You can think of the differential in your car if you like, OM; the turning or bending of the wave path is the logical result. The top of the wave fronts traverses the ionosphere at a phase-velocity greater than c, but merely "walks through" the modulation envelope. So our audio modulation gains no time in getting to the receiving site, no matter how long the radio waves spend in the ionosphere. Thus is the axiom complied with that information can be conveyed only at group-velocity, which can attain c but often is somewhat less.

Adding a few more points of info to your recall, OM, radio waves do propagate at speed c in free space, both group-velocity and phase-velocity are then equal to c. Under other circumstances, such as when the rf is being conveyed from your rig to the antenna, the group-velocity in the transmission line may be only around 60% of c. In air, the group-velocity is very slightly less than c. In general, group-and phase-velocities have inverse relationships — a group-velocity below c tends to be accompanied by a phase-velocity above ct

Admittedly, OM, all this business about radio-wave propagation and modulation-transit time came up in a roundabout way. if 1 cominue to pursue it in its pedagogic details, nothing greater will be accomplished than a cure for a few cases of insomnia. Instead, I cordially invite you to direct your attention to some rather strange events which just happen to relate to much that has been hitherto discussed. And I promise not to bore you with further allusions to my oscillographic teaching aid- Despite its money-making potential, its challenge to the imagination pales mto insignificance alongside the electronic marvel you are about to encounter.

My relevant and. I hope, believable experience commenced a couple of months ago white driving on one of those long, straight, and scenery-less roads connecting a series of small towns. To relieve the boredom, I had fired up the mobile rig and was busy rag chewing on 40-meter SSB with a ham in the big city several hundred miles due south, lor a time, all went well Our mutually S8 signals were unencumbered by either QRM or QRN, but, with the passage of time and miles, I began to notice a diminution of his signal strength. Then, within a period of, say, ten minutes, it rapidly became impossible to copy him; the QSO was abruptly and inadvertently terminated.

Now you might contend that there need be nothing out of the ordinary in such an occurrence. OM, you ¡list may be as right as apple pie, but allow me to cite the following strange phenomena which accompanied this fade-out, • The increased distance between us during those ten minutes was, percentagewise, tri\ ial.

• it all happened between two and three o'clock in the afternoon, so there was no dawn or dusk transition

• All the time his signal was becoming weaker mine was reported to be getting progressively stronger In fact, his last discernible comment was/'Hey, OM, it sounds like you are right smack on top of me now!"

• Other frequenc; scanned on 40 meters wei dead, as were also the 20-and 80-meter bands.

• The car radio delivered a lot of noise, but responded to no broadcast stations.

While my befuddled mind was trying to resolve this very eerie package of propagation a noma lues, the first traffic light \n thirty mtles abruptly shattered the continuity of my thoughts. And it was as red as the grid of an overdriven linear. Obeying its command, I came to a stop and made ready to greet the green light with the usual great leap forward. But this beacon of the highways was in no hurry to accommodate my impulses- Indeed, it exhibitedl a downright sadistic behavior, obviously enjoying its prolonged red glare while I fidgeted and gnashed my teeth, to say nothing of my nearly mashing a few gear

Fig. 2. DX via skip involves wave speeds greater than the speed of light in free space, (A) The speed of propagation does not exceed c, the speed of light in free space. (B) Top portions of wave fronts exceed c, thereby causing bending of the propagation path, (C) Once out of the ionosphere, the situation is again as in Region A.

GQO0 OLtt TtNHfi FlRWr",

GQO0 OLtt TtNHfi FlRWr", teeth in anticipatory but quickly halted starts, "Shoulda brought my camping equipment/' I recall muttering

Perceiving the utter futility of contention with my source of annoyance, I wisely decided to relax and practice the time-honored virtue of paUence. Observing the countryside around me, my attention was attracted to a small bungaiow-like place of business slightly recessed off the road and about fifty yards ahead. Adjoining it was a parking lot with several late-model, luxury-type cars. (Compared to mine, this might include almost anything, OM.) I found myself pondering the nature of the wares or services sold so far away from a business community. Surely, OM, you can fathom the uninhibited conjectures that came into my mind! "What a snazzy ham shack arid antenna farm I could make out of that combo!" I fantasized.

But this was no han. shack, for large ^igns on the gabled roof clearly delineated the operations therein performed. This was the abode of one Madame ZH who purported to possess inordinate insight into the past, present, and future —for a fee. A small sign conveyed the additional information that the stated fee was payable in this time domain, the present

"What a bunch of balderdash, baloney, and blarney!" I declared to imaginary seekers of ultimate wisdom, At the next moment, I dug out in response to the long-awaited grern light But this is where the karma of my life (or, perhaps, a past existence) asserted itself, for if there was one thing the ancient buggy did not take kindly to, it was acceleration. Amidst the coughing, wheezing, and misfiring of the uncooperative engine, I had ample time to notice that Madame Z had opened her front door and was staring at me as if in retaliation for my rather uncomplimentary attitudes about her alleged faculties.

Time seemingly slowed down, and Ï feit the pangs of remorse best known to reprimanded schoolboys (Prachcal-minded readers certainl\ have the right to attribute the slowdown to the Tdsel,) Time distortion or whatever, OMd I clearly saw that this pert young seeress was a mini-skirted e\ eful — quite the converse of the stereotyped ntch we may tend to associate with this profession. Being basically an open-minded sort, t found myself acknowledging the vast strides modern science has made in parapsychology. Indeed, had I not been on the way to a business appointment in the upcoming town, 1 would have stopped by for an objective discussion of psychokinesis, ESP, and other occult manifestations such as the attraction between oppositely-polarized entities. Suffice it to say, OM, I don't think the "other" traveling salesmen ever beheld such a farmer's daughter as this!

inasmuch as my perverse clunker refused to break down or run out of gas in this vicinity, 1 finally arrived at my destination — not, however, without the observation that the bands became mysteriously alive again, once Madame Zs facilities were out of sight.

Well, OM, far be it from m\ intent to bore you with the details of my business activities at the thriving metropolis of Hicksville — pop. 549. Nor shall I indulge in naïveté by pretending that you have not lumped the gun on my unraveling tale. Obviously, 1

was destined to visit Madame Z on my return trip. Let us just say that I was overwhelmingly intrigued wjth the halo of rf shielding surrounding her "ham shack." And so it was — I parked the flivver on her "antenna farm/' jumped out. and proceeded up the several steps leading to her door

There was no need to knock, for the door magically opened, revealing the very shapely shape of the madame! I found myself being more than cordially escorted to a chair alongside a small table. I couldn't still the strange feeling that my entry at that very instant was expected— or was it planned? In any event, I assured her that 1 had no problems whatsoever in either the fecundiary or the fiduciary domains. The whole atmosphere was dreamlike, OM, and Madame Z chose to ignore my prevarications. We seated ourselves on opposite sides of the table. On the one hand, I felt trapped, On the other hand, I felt enraptured with the pulchritude of this very delightful oracle!

"I feel that you are a person with much technological insight, and that you are immersed in a fascinating hobby having to do with an applied science/' cooed the seeress.

I reflected on her probable observation of the transmitting whip on the flivver, to say nothing of my call letters written ail over the piace

"You must learn to relax your hostilities/' she admonished, much to my embarrassment. "Are you an amateur operator?" came the inevitable question.

I nodded in affirmation. I also thought that she should be telling me, rather than asking me things, if she expected our tête-à-tête QSO to culminate in enhancement of her mate rial well-being in this present existence. But all vestiges of suspicion, opposition, and unease speedily evaporated as a consequence of her next deduction. That she was endowed with a truly uncanny insight into the occult I could no longer doubt.

'Radio amateurs are greatly esteemed b\ the psychically sensitive. None in this incarnation possesses a more positive mix of the ultimate virtues. These include intelligence, achievement-oriented behavior, self-policing morality, impulsion for high adventure, and wisdom beyond attainment in our systems of formal education/'

Silently, but graciously, I accepted her eerie deduction of facts well known to hams anywhere and everywhere, but not always recognized by those outside the realm

In addition to revealing these truths about hams in general Madame 2 unraveled a lot of nice things about this particular ham —things that were buried even beyond my own conscious knowledge. But, OM, what really will be of interest to you is not what she said, but what happened then and there, right before my own two eyes. For while the seance was proceeding, a giant crystal ball materialized a couple of inches above the table. For sure, OM, there was nothing on the table when we initially sat down!

So I found myself beholding this levitated sphere. It was about two feet in diameter, and was slowly rotating about an unseen axis inclined about 45 degrees with respect to the table top. Because my sensual acuity had been strangely awakened to a degree unimaginable in everyday life, I perceived a heck of a tot more than the

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