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What got you the DX bug?



In the case of KOMA, you have to have heard it in the late 50's and into the 60's to understand that it was the station for younger folks from Eastern Montana, the Dakotas, much of Wyoming, Eastern Colorado, New Mexico, West Texas, Oklahoma and much of Kansas and Nebraska.

There was a lot of advertising for shows and movies. "... the 9th in Jamestown, 11th in Fargo, 12th in Bismark, 13th in Yankton, 14th in Scottsbluff, 15th in Lamar and the 16th in Tucumcari" would be a common tag for a rock and roll show such as the one that aired, saying, "February 2rd at the Surf Ballroom in Clear Lake and February 3 in Moorhead" a few days before the music died.

KOMA, at night, was the "local station" for that entire piece of the Midwest and eastern Rocky Mountain West.

I'll vouch for that. I was there (in Iowa). There were ads of that type every night at least 2-3 times per hour.
 


Nobody had to null KOB.

I can recall hearing it clearly in Houston until the radio was turned to null it. I had never had any luck with WABC from Midland, because KOB was just too strong at night.

My last experience with KOB was when I was investigating how co-channels would affect C-Quam in the early to mid 00's. I pulled into a rest stop in Crosbyton, TX, right in the middle of a canyon about 11AM. I had a Sony SRF-A1 with me. KMKI had a trace of static on it but C-Quam was beautiful, not a trace of platform motion off the wall of the canyon. Not the case with KAAM, which was weaker and had KKOB in the background (they added an extra K by that time). The left and right channels slowly swapped places. It wasn't too bad to listen to, but not a pleasant thing right at the swap. It only got worse by Lubbock, where KKOB's signal was almost a match for KAAM, and nulling wasn't too effective because the directions were similar, by the time KKOB was gone there was enough attenuation on KAAM to make it hard to listen to. KMKI had considerably more static, that additional 40 miles was not kind to it. Nevertheless, I encountered a small - but fanatical group of KMKI listeners, who were quite adept at stringing longwires, hunting up old AA5 tube radios, etc. - and knowing when to tune 1160 from San Antonio and 1690 from Denver to get the network. No AM stereo listeners, but they seemed quite impressed with a GE Superadio 3 and wanted to know where to get one. Remarkable because they were in their early teens. Interested in the music Radio Disney was playing. All because I carried a portable to a community pool and turned it on Radio Disney. It didn't take long for me to be surrounded by the curious kids!
 
It's kind of fuzzy where you draw the line between regular reception and DX. The FCC came up with new skywave curves, and the old statement about "38 states" and "750 miles" went out the window. If we are strict, many of those areas within the old 0.5 mV/m 50% Skywave are no longer in it, so they would be DX. And then, if you are just outside the NIF, it is DX. Then there are now many high power Class B stations with 50% skywaves of several mV/m but are unprotected. But they have 20:1 D/U de facto skywave service. That argument against it being DX was often used to justify NOT sending out QSL cards. When stations got too picky, I stopped sending reports and wasting postage.
 
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It's kind of fuzzy where you draw the line between regular reception and DX. The FCC came up with new skywave curves, and the old statement about "38 states" and "750 miles" went out the window. If we are strict, many of those areas within the old 0.5 mV/m 50% Skywave are no longer in it, so they would be DX. And then, if you are just outside the NIF, it is DX. Then there are now many high power Class B stations with 50% skywaves of several mV/m but are unprotected. But they have 20:1 D/U de facto skywave service. That argument against it being DX was often used to justify NOT sending out QSL cards. When stations got too picky, I stopped sending reports and wasting postage.

That's a good "non emotional" way of looking at it.

My feeling that any station you can get reliably enough to listen to very regularly with the expectation of having a usable signal is not DX.

That expectation has changed over the decades. I suppose that a listener to the Opry in Montana in the 30's knew that there might be summer nights with too much static and noise for good reception*** but they listened regularly, despite that, because there was nothing better to hear.


*** I have a theory that the reason why, even today, network TV shows do reruns and fills in the Summer is due to the long-ago reduction of network reach back in the 30's in those months of high atmospheric noise. It started a habit that is with us today... and which opened the door to "off season" cable successes like Mad Men and Walking Dead that took advantage of a vacuum that desperately wanted to be filled.
 
I can recall hearing it clearly in Houston until the radio was turned to null it. I had never had any luck with WABC from Midland, because KOB was just too strong at night.

My last experience with KOB was when I was investigating how co-channels would affect C-Quam in the early to mid 00's. I pulled into a rest stop in Crosbyton, TX, right in the middle of a canyon about 11AM. I had a Sony SRF-A1 with me. KMKI had a trace of static on it but C-Quam was beautiful, not a trace of platform motion off the wall of the canyon. Not the case with KAAM, which was weaker and had KKOB in the background (they added an extra K by that time). The left and right channels slowly swapped places. It wasn't too bad to listen to, but not a pleasant thing right at the swap. It only got worse by Lubbock, where KKOB's signal was almost a match for KAAM, and nulling wasn't too effective because the directions were similar, by the time KKOB was gone there was enough attenuation on KAAM to make it hard to listen to. KMKI had considerably more static, that additional 40 miles was not kind to it. Nevertheless, I encountered a small - but fanatical group of KMKI listeners, who were quite adept at stringing longwires, hunting up old AA5 tube radios, etc. - and knowing when to tune 1160 from San Antonio and 1690 from Denver to get the network. No AM stereo listeners, but they seemed quite impressed with a GE Superadio 3 and wanted to know where to get one. Remarkable because they were in their early teens. Interested in the music Radio Disney was playing. All because I carried a portable to a community pool and turned it on Radio Disney. It didn't take long for me to be surrounded by the curious kids!

The null on KOB/KKOB is to the NE of a line drawn roughly from ABQ to Lubbock to Austin to Houston. So you may have been just well enough on or inside the line to have had a decent signal.

Platform motion was resolved by Motorola some years after the introduction of CQuam. Some stations updated the equipment, some did not. Others just yanked it when, by the early 90's it was obvious that the system had gone south for a never-ending season and nobody was listening.

One thing that I did with our engineers at KTNQ in LA was to drive the signal in the sides and centers of the directional system nulls, with and without CQuam. Based on our nauseating experiences, we decided to yank the gear. Ratings in null areas went up significantly after that decision was made.
 
I'll vouch for that. I was there (in Iowa). There were ads of that type every night at least 2-3 times per hour.

And the movies: "Starting Saturday at the Grand in Sturgis, the Gem in Ogalalla, the Orfeon in Coffeeville..."
 
@ David E :

Once again I have to skate in between your definition of genuine DX and that of the fine post by Schroedinger. And certainly, the slalom is from a personal/anecdotal recall to be sure. But the instances were too numerous to dismiss somewhere between ennui and 'bad local radio' that didn't * do it * for those prodigal dial twisters -- all of whom were female.

Now, I'm not Robert Redford nor JFK Jr. But I somehow managed to date, romance and/or otherwise observe my share of various young lasses during my Twenties years. Every one of them were either bored by local radio or exploring elsewhere to hear their enviornmental metier. Two of them, from Long Island, regularly shunned the three Nassau-Suffolk AoR stations on FM to tune in WDRC-FM and WPLR Connecticut. They went where their music was.

One gal and I were driving along Linden Boulevard in Brooklyn one night listening to some pop-music station on 1200. I'm yakking away about the neighbourhood. She says, 'Shut up.'
'CFGO Ottawa' came the ID out of the speaker.
'Now: As you were saying?' the girl asked.

One gal from Queens vacationed with her Folks at Greenwood Lake NY. She mailed me this glorious postcard from there, saying that she heard Joey Reynolds off WKBW Buffalo on the transistor she'd smuggled along.

And once, a gal and I were driving one day along the Long Island Expressway, headed east. And there appeared this tower off to our right, in what was property of 'Brentwood' Town/Township.
The station originally was in the same building as WGSM 740 Huntington. It was their FM. At the time we passed by the tower, both WGSM's and their studios were in Melville.
And she said, somewhat snootily: 'Well, there it is. WCTO. Smithtown.'

Boring local radio turned some people into DXers. They had to explore -- male, female, hobbyists or casual folks or in between. Oft times, the locals had no choice but to seek elsewhere for the devil's music, lol
 
I was maybe five years old, and already a geography enthusiast, from some old maps of the northwestern US states my parents had given me. When you're a little kid, the next state over can seem like another country. Maybe in today's internet climate it isn't that way anymore, but pre-internet, that's the way it could be.

One night I was tuning the AM band and heard Oregon, and I was hooked. To me, it was like hearing a foreign country, and of course, with the way the AM signals phased and faded -- they sounded like they were coming from far away. Any time I'd catch a new station I'd look it up on the maps and see where the station and city were located.

Over the years the radios changed from an old RCA console to a Japanese 3-bander (AM-FM-SW -- I heard WSM, WWL, WBAP, KOB, and WLS on that one), to a DX-160, to a Sanyo boombox (hence my nickname here), to Superadios and other portables.... But generally my "DXing" is about the same. I don't really go for the hard-core stuff anymore, trying to boost the station numbers, especially when the past couple of MWDX seasons have been fair-to-middlin', and most nights I hear the same 300 stations; but I'll tune in merely because it's more interesting to me to hear something from far away than it is to hear a local FM station playing the same songs I've already heard several hundred times.

Lately I've been listening to 1600, a mix of South Asian classical music overnights (KVRI) mixed in with classic hits (KUBA), ESPN (Colorado?), and some talk (KOHI). While I type away I just listen to the formats phase in and out and it's more interesting to me than a lot of other stuff on the dial currently.

I do listen to local FM from time to time, mainly the local rock and alternative stations. And tune the SW bands maybe 3-4 times a week (they're mostly dead anymore). But the MW band holds the most interest mainly because of the geography -- it's like taking a weekend road trip somewhere 250 miles away without leaving the desk chair.
 
Boring local radio wasn't a problem in our area of SE Iowa while trying to receive the devil's music. KIOA daytime, WLS-KAAY-KOMA nights. DX may be in the ear of the beholder, but I'd define DX as a reliable signal from KIOA 940 Des Moines at night, which was only 60 miles to the NW of us, but we were on the backside of their pattern. Add regular interference from the former CBM 940 Montreal and it is no surprise that a few of my friends thought KIOA was a daytimer. The summer of 1973 found KIOA with a week or two with a very strong nighttime signal. Hooray, I thought...they've boosted their power. In all likelihood KIOA was having some problems with their DA. One day KIOA was off-air for several mid-morning hours. Afterwards it was back to the usual puny nighttime KIOA signal.

Around this same time I started collecting QSL cards from commercial AMs to go along with the half dozen or so QSLs we received from amateurs and CBers, some from several states away, that picked up our puny 5 watts of CB channel 6 in the early 60s. Just as we abandoned CB in the late 60s, I learned after about 30 SASEs sent with a return rate of maybe 20% that most AM stations couldn't be bothered with QSLs in the 70s. Wished I'd rescued the channel 6 CB QSLs but they got away. So did my QSL from KWMT 540 Fort Dodge...not at all DX but they did like to brag about Iowa's Largest Daytime Coverage.

After that DX was for my own satisfaction. Never could log a West Coast station from Iowa...not even KFI. In the late 70s and early 80s, armed with a Technics SA 5170 receiver bought w/ my part-time job, RatShack FM rabbit ears and a MacIntosh FM radio atlas, I started chasing tropo events and the occasional E-skip event. Tropo tended to favor states to the south and east of Iowa. South Dakota was a tough catch for ducting; Kentucky was an easier catch. E-skip ranged from Saskatchewan to the East and Gulf coasts. In the 80s, when the DJs were almost always live, I called an FM in Florida and got myself on the air.

The Technics receiver was as numb on AM as it was hot on FM. Not much tropo in Colorado so it's in the closet awaiting a general cleanup after 40 years.
 
Also what got me to DX around 2000 or so was the ample open frequencies in the area. Nothing like the 80s or prior, but DX was good even on a little RadioShack portable like I had. My favorite part of the radio back then besides the DX was the jingles played. Many FM stations had great jingle packages.

WTCB from Orangeburg on 106.7 (75-80 miles away but didn't come in all the time), was one. What I liked was they always had a local personality on, no matter what. They also had a weird legal ID. The air personality would sneak in the legal ID in the middle of the weather report. For example, he or she would say, "WTCB Orangeburg has 73, Columbia 71." I even noticed that at my young age.

They'd then have a legal ID jingle, "WTCB, Columbia!", even though it has been licensed to Orangeburg for decades.
 
Joe, one night at Torino's pizza in Fairfield, I had my walkman with me, and heard both KFI and KNBR. The only time I ever heard them in Iowa.
 


The null on KOB/KKOB is to the NE of a line drawn roughly from ABQ to Lubbock to Austin to Houston. So you may have been just well enough on or inside the line to have had a decent signal.

Platform motion was resolved by Motorola some years after the introduction of CQuam. Some stations updated the equipment, some did not. Others just yanked it when, by the early 90's it was obvious that the system had gone south for a never-ending season and nobody was listening.

One thing that I did with our engineers at KTNQ in LA was to drive the signal in the sides and centers of the directional system nulls, with and without CQuam. Based on our nauseating experiences, we decided to yank the gear. Ratings in null areas went up significantly after that decision was made.

Yes, your comments about platform motion prompted me to do that stop in the Crosbyton Canyon. If there were ever a horrific listening scenario - 290 miles away, steep canyon walls would definitely be a worst case reception scenario. I hiked all over the place for an hour or two with headphones on - no platform motion on KMKI at all. They must have had the problem corrected - as you suggested. Perhaps instead of yanking, you should have gotten the updated gear.

Something, though, doesn't quite add up. If C-Quam was going nowhere, nobody was listening, so stations pulled it - you would think that by now there wouldn't be a single remaining HD-AM station. I know that I get anywhere near a power line, and HD AM is gone. Power lines probably are along side of 99% of streets and roads in the country. Which means HD-AM will not work in a car. As far as home listening, the ever increasing series of noise makers, from CFL bulbs to home networking - combined with radiant barriers making houses virtually into Faraday cages - and HD AM doesn't have a chance in homes, either. Yet we still have owners tenaciously hanging onto a technology that failed worse than C-Quam with consumers. Doesn't make sense. At its very best, I only got 35 mile range on AM with KMKI - as opposed to 300 miles with C-Quam. At night WLS C-Quam boomed into Houston in the 80's, close to 1000 miles. I've never heard anybody make that claim with AM HD. Inferior technology, not catching on with consumers, why are there still AM HD stations?
 
Platform motion was resolved by Motorola some years after the introduction of CQuam.
Could stations then apply asymetric modulation?
I remember having receivers that would shift the balance to one side
(I do not remember which side) on C-Quam stations.
 
Could stations then apply asymetric modulation?
I remember having receivers that would shift the balance to one side
(I do not remember which side) on C-Quam stations.

Are you thinking of the Kahn / Hazeltine system by any chance? You could get stereo - of a sort - using two radios. One tuned to one sideband, the other tuned to the other.
 
I hiked all over the place for an hour or two with headphones on - no platform motion on KMKI at all.

Platform motion was only noticeable in a motor vehicle going at highway and freeway speeds. At hiking speed, you would never notice it. The motion did not have to do with multipath (mountains and hills and buildings) but with phase issues at wavelength multiples (at least that is what their technical bulletins said...).
 
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I never got to ask Mr. Kahn this, but is your interpretation that (R-L) HAS to phase modulate the carrier at SOME amplitude with the Kahn Hazeltine system? In Mr. Kahn's article in the NAB Engineering Handbook 1960 edition, he clearly shows that his FCC-SSB system phase modulates the carrier. So if there are two rotating sideband vectors, one CW and the other CCW, if R=L there is no phase modulation, but if R is not equal to L, then (R-L) phase modulates the carrier in some fashion and matrix amplitude. Is this THE SECRET that Mr. Kahn talked about, that if you inject a Motorola pilot tone, or if it "falses" from random audio simulating the pilot tone, that the Motorola chip recognizes it as phase modulation and decodes Kahn Hazeltine as Stereo at least somewhat?
 
I was a little child that I like to listen to local stations in the area. and then Some years after that I moved on into weaker stations in the area or outside of My area I've listened to such as Dayton, Ohio, and other radio stations. I have listened to some radio station signals in the northern side of My home city of Cincinnati. There was a school that is in a field I used to be attended. I've always listen to the really weak radio stations in the area of the location. Some of the really weak signals are from a city and some other parts of that location I've listened to. Then My dad told me about you could get all types of radio stations. At first, I think He ment the daytime, but That would be impossible. After that I did some research and then some of the websites talked about the NIGHTTIME more than the daytime because All of the AM radio stations will appear at night. For example : WMVP 1000 is coming in every night. Then I tried on My new RadioShack radio and then at the nighttime, All kinds of radio stations are coming in at night. I was excited to discover this. At first it would be impossible, but I was wrong. Nowadays. I sometimes listen to the AM radio for some difficult radio stations like WCPC 940 in Houston, MS.
 
...but is your interpretation that (R-L) HAS to phase modulate the carrier at SOME amplitude with the Kahn-Hazeltine system?
It is my understanding that with this system,
there were no sum and difference complexities.
Simply, the left channel was on the lower sideband
and the right channel was on the upper sideband.
I have no idea how this was accomplished, just the result.
It had the advantages that the stereo range was 100% equal
to the monaural range and with no hiss or extra noises creeping in.
 
Here's the section from the 1960 NAB Engineering Handbook, courtesy of David's great archive. It starts on Page 32 of this section. FCC-SSB appears to be the forerunner of the Kahn AM Stereo System. Instead of one sideband, there are two sidebands. The two sidebands would have half the amplitude of the single FCC-SSB sidebands. One sideband would rotate CW, the other CCW. If for example, L=0, then you would have a single vector of half the amplitude rotating CW. This would phase modulate the carrier. Then consider two modulation vectors, half the amplitude, and R=L, identical sidebands. While the rotate in opposite directions, the x axis vector components cancel, and you have no phase modulation, and a waveform identical to AM DSB monaural, When R is not equal to L, the x axis vectorial components are not equal, and there is a deviation in the phase around the carrier phase. Hence some amplitude and type of phase modulation. The simplest stereo case would be one audio frequency in the USB and another audio frequency in the LSB. You could model the waveforms with a simple BASIC graphics program. I think the phase modulation is "THE SECRET", because it was MARKETED as if it was completely different with independent sidebands, with no phase modulation. I don't see how there could not be phase modulation. Motorola wanted its pilot system "protected", that is, prevented from being used by Kahn or other systems, so that Kahn couldn't just put the pilot in and have the Kahn system detected by the Motorola system chip in some way, and have some matrix form of stereo audio. That "false" activation, and also platform motion, was due to random audio frequencies combinations simulating the pilot, and two or more cochannel beats simulating phase modulation.
 
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