RADIO & TELEVISION NEWS December 1952 - p. 52 http://www.americanradiohistory.com/Archive-Radio-News/50s/Radio-News-1952-12-R.pdf for images and diagrams [captions of which are in brackets below] DX TELEVISION By STAN JOHNSON, W0LBV THERE are cowboys on Peachtree Street in Atlanta, Georgia - the Johnsons know, because we've seen them. The only thing remarkable about this fact is that we saw them from Denver via a television signal loosed from the transmitting tower of WSB in Atlanta - months before Denver had a television station of its own! Because Denver was one of the most television-hungry cities in America - the largest to be caught by the "freeze" without a station - it became the center of an extremely active group of television DX-ers - of whom the writer was one. From the experience of this group has come some practical ideas to help you pull in long distance television - and enjoy one of the few real thrills left in radio. The writer's interest in television DX was sparked by work on an article which appeared in RADIO & TELEVISION NEWS this past year - and dealt with DX-ing by a service technician in Longmont, Colorado. After seeing what could be done, it was inevitable that the Johnson family would acquire a television set, despite the fact that at that time it appeared television for Denver was a long ways away. The set, however, was nothing fancy. It couldn't be because it had to be lugged from San Francisco, where the writer happened to be on business. Furthermore, there was a little matter of explaining to the XYL that a tele- vision set was something the household could not do without, and that those new drapes for the bedroom could wait. (How to sell an XYL an idea like this will be discussed later - so read on!) At any rate, the set chosen was a little second hand 7-inch Admiral, which sold for $50.00. Sharpies, with time to shop, have been known to buy similar 7-inch sets for $25.00 or less. The little set managed to survive the trip all right - and was brought home and hooked up - in late January. Wonder of wonders - for a few fleet- ing seconds one memorable Sunday morning - it brought in a picture. But all of the dope said that sporadic "E" reception wouldn't begin until May - and unfortunately, the dope was right. For weeks the little set produced nothing - although by this time the XYL was becoming interested enough to monitor Channel 2 several times a day - and the Number Two Son had learned to say something which sounded like "no pictures today, Mommy." [Jim Livesay, W0TRP, has logged over 20 DX television stations. This new "hobby" has gained a tremendous following in the U.S. Despite the fact that TV stations are springing up all over the U.S., television DX-ing still has many ardent adherents.] Meanwhile, the OM, being the conservative type, had decided that a booster might be a good idea, so had parted with another $10.95 to buy a "bargain" 6J6 booster. Then, one evening - May 3rd - the 10-meter phone band came alive with a bang on "short skip." So it was time to check the theory that if 10 meters was open, Channel 2 should not be far behind. Bright and early Sunday morning the little TV set was turned on. And there it was - intermittent-fading - but a picture: KPRC in Houston, Texas. Because the picture seemed to be a bit mussed-up, it was decided that the home-brewed V-beam being used was probably causing ghosts - so a standard TV antenna (Dubl -V) was hastily erected on a rotating mast assembly - and we were ready to try again. The next chance came on May 9, and the XYL reported that the picture still displayed people with three heads - so the OM knew that he had a service job on his hands. It turned out to be nothing more complicated than replacing the horizontal oscillator tube. One fact was already apparent - the wire V-beam, which cost less than $2.00 to erect, was a lot better than the smaller Dubl-V. And it became evident from checking with other hams and TVL's in the city that the big V-beam has the pleasant habit of brewing up signals when large stacked TV arrays, and much hotter receivers, weren't doing a thing. The V-beam was about as simple as an antenna could be - consisting of two wires (see diagram) fed with a feeder on one end. An open wire line (the original was homemade but the Gonset line would be ideal) was used to tie the antenna to the set. Fine on Channel 2 - which after all is fairly low frequency. But surely a standard TV antenna would do the job better when the higher frequencies opened up. On May 17 they did - with a bang - signals coming in as high as Channel 5. In every case the V-beam outperformed the TV antenna - in any direction - and the average held true all summer long. Further cross-checking with other listeners showed that the beam was staying in there with the best of them - and out-performing all but the best. Exactly why the writer doesn't know. However, here is a theory, for what it is worth. Big stacked arrays have as their basic purpose concentrating reception at very low angles - a factor which is probably more important than sheer gain in fringe area reception. But TV DX is fairly high angle. And a wire V-beam is a fairly wide angle device - capable of receiving from a number of angles - and from many different directions. Likewise, having a lot of wire out seems to give better over-all efficiency - or as one practical soul put it - gets a "better grip on the ether." However, the V-beam does have one serious disadvantage - it picks up signals from many different directions at the same time. And until you have seen TV stations pile up five deep on the same channel you don't know what interference is. So - in the writer's opinion - the best answer for the antenna problem is to put up a V-beam for best reception when signals are coming in chiefly from one area. And then have a rotating array, with an antenna with a fairly good front-to-back ratio, to allow selection should there be several stations coming in on the same channel but in different directions. So much for antennas. But when do TV signals come in ? Again there is much opinion in all of this. But the opinion of Denver listeners - and their logs - seem to show a definite pattern. The writer's own log clearly gives the morning hours the nod during the summer season of '52, with a lot of signals coming in as early as 7 a.m. - with 10 a.m. being a particularly good time. Relatively few signals were logged at noon - but the afternoon hours showed more signals -and the early evening second only to the morning. All of this boils down to the fact that there might be signals to be heard (or seen!) almost any time - so it would be nice to know when to listen. As mentioned earlier, it seemed to the writer that monitoring the 10 meter phone band was an easy way to get a tip-off on good skip conditions. And the experience described previously was no fluke - not once in months of listening did TV DX come in at a time when there was no short skip on 10 meters. However - unfortunately - many times skip did come in on 10 when TV was dead to the world. Even so, the cue, obviously, is to watch 10 meters. If that band is dead for short skip (reception under 1000 miles) go shoot pool, or mow-the lawn, or something, for TV DX probably won't happen. But when the 10 meter band comes alive with short skip signals, get a can of beer and stay with the TV set, because something is probably going to happen. If you are an experimenter at heart you may want to test anther theory - not the writer's this time, but that of one of the champion "DX-ers" among the several hundred in Denver who did a lot of listening - or watching: Jim Livesay, WOTRP. Jim, who is an engineer, and whose background includes several years as an officer in the Signal Corps, is now general engineer for the Colorado Central Power Company. In this capacity, part of his job is to keep an eye on the company's high frequency radio gear, operating on 47.94 megacycles, used to maintain communication with company trucks. Jim noticed during 1950 that during the summer months quite frequently "skip" signals from other services would interfere with local communication. He reasoned that if 47 mega- cycles would come alive, so should Channel 2, and on the strength of that idea bought a TV set. In '51 he received stations intermittently throughout most of the summer -and during December and early January of '52 had some excellent reception. His receiver is a 17" Admiral - with a good booster and a parasitic array, cut for Channel 3. The antenna, a yagi, is a bit unusual in that the tubing used is quite large in diameter, the idea being to get as wide a band of response as possible, in order to cover the low frequency channels. (The limitations of any parasitic array in frequency coverage are one of the reasons the writer chose two types of driven arrays.) Livesay's carefully-kept log shows one highly-interesting thing: in Denver, at least, almost invariably sporadic "E" skip during '52 came during times of high barometric pressure - and since the barometer would go up first, it served to give some warning that conditions were about to be favorable. Never once, according to Jim, was skip received when barometric pressure was low. He doesn't regard his observations as at all conclusive - but perhaps other DX-ers will test it further. Jim was one of the first DX-ers in the Denver area, and when his activities became known through a news story in the Denver Post, he became the unofficial "Paul Revere" of a network of listeners. When the 47.94 megacycle signals at the power company began to show signs of skip, he would give his attractive wife, Trudy, a ring - and she would watch for signals to appear. If they did, she would, in turn, call others in the "network" [TV DX stations are not necessarily weak. Some pound through like locals. Here's proof, in the form of a picture of KPRC's (Houston) pattern as received in Denver.] [THE LONGER LENGTH PREFERRED 4 ç, BOTH LEGS ARE IDENTICAL APPROXIMATELY TO THEORETICAL BEST DIRECTIONS No. IB COPPERCLAD STEEL OPEN WIRE LINE TO TV SET OR BOOSTER] [Top view of WOLBV's TV DX antenna. With this simple receiving gear - a three-year-old 7" TV set and "bargain" booster, plus a good antenna, author has picked up stations from Pittsburgh to the Pacific.] Television DX (Continued from page 53) -and in a matter of minutes a lot of TV sets would be perking. Getting the XYL - or "wife" to the uninitiated - into the act is pretty important, unless you are working on a job in which you can monitor signals during the day. For a lot of the best "openings" occur during the daytime, when the OM is off earning a living. What is a typical "opening" like ? Let's take a look at the log for June 18th. At 9:00 a.m. Houston began to make an appearance - with diagonal bars appearing on the screen, which occasionally would break into a picture. After an hour or so the picture would stay in sync most of the time, and the sound came up to the understandable level. At 12:45, Houston dropped out completely. But at 3:30 p.m., WSB in Atlanta appeared, with an excellent picture, which lasted for a couple of hours and got better and better. So it was expected that more signals would develop, and sure enough, at 5:30 KOTV on Channel 6 in Tulsa came in, followed by KEYL, San Antonio, and WAGA, Atlanta, fighting it out on Channel 5. At 8:30 p.m. Atlanta was back on Channel 2, but there was some interference in the background. The interference finally grabbed the ball, and it was KTSL in Los Angeles. KTSL dropped down into the snow after a few minutes - but was still making diagonal bars on the screen at 10 p.m. The next morning a new one, WDTV Pittsburgh, pounded in bright and early at 7:10 a.m. on Channel 3. An unidentified station was on Channel 4, and another on Channel 2. At 9:00 a.m. WJBK was identified on Channel 2, and at 10:00 a.m. WKZO Kalamazoo came in. During the next couple of hours several more stations were picked up but not identified - and not until KPRC reappeared on Channel 2 at 7:30 p.m. was it possible to get call letters. KPRC stayed on for a few minutes - then faded out - and the "opening" was over. Two days elapsed before another signal was picked up, when KNXT in Hollywood appeared at 11:35 a.m. with a good picture, but not one shred of sound, to be followed a couple of hours later by KRON on Channel 4 in San Francisco -and another "opening" was on. The "openings" mostly follow a similar pattern - with the more distant stations being heard first and last - and closer stations in between. Likewise, most of the time signals appear first on Channel 2, then on the higher frequencies up to Channel 6 if conditions are ideal, then gradually work back to Channel 2. There are exceptions - but Channel 2 is the channel to watch the most. But what if you have a local station on Channel 2? Then Channel 4 is probably your other best bet - because there is pretty apt to be interference on Channel 3 from the local. If both Channel 2 and 4 are occupied, better find some other indoor sport except when the locals are off the air. If there are no interfering signals - or if you are one of the many people in areas with one or no stations - then TV DX-ing is a lot of fun. And it is about to open up again - for the records show that December is the next best month to June for TV DX-ing. After mid-December you should receive it quite frequently. It will drop out in January - but you will have had a crack at it. Actually, long distance TV reception has a lot of practical angles. It provides a way for the technician to get a crack at actual reception before a station opens up nearby. It will provide local publicity. But most important, in the writer's opinion, is that it gives the old hand at radio an intriguing new experience. The writer - who was winding coils at 14 years, and trying to coax in the London BBC station on a one tube UX-199 short-wave set - has worked the world with a 10 meter phone rig. But no thrill in radio ever quite came up to that of seeing the snow fall away and the first long distance TV station corne threading in. There is something a bit magic about TV - which is above and beyond ordinary radio. And - there is something else. Ten years of salesmanship hadn't convinced the YF that ham radio had much to offer. But something about scooping the neighbors with TV seems to the intrigue the lady of the house - or at any rate, intrigued one lady - who actually logged most of the reception at the Johnsons. In fact, she was a little sad, as was the writer, the night recently when KFEL-TV Channel 2 broke the silence in Denver and came on the air - in the process killing off the best TV DX band. But the other night a husky signal began interfering with KFEL's signal - not too strong, because of a temporary set-up. The best guess was that it was Los Angeles. And a quick trip to Channel 4 revealed San Francisco coming through - the picture weak, full of snow, dropping in and out of vertical sync. But DX! Everything seemed right again. December, here we come! 30