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On Sun, 14 Oct 2018 08:50:13 +0000, Spike
wrote: Stephen Thomas Cole, the PP, just after gaining his UK Full licence by 'acing' all three exams, appeared on a UK Amateur group asking which sideband he should use on 40m. That’s all you need to know about him and and his ability with radio. For what it's worth, I don't know which sideband to use on 40m. That's because I don't operate much on 40m and don't have such details memorized. I use a wall chart with the appropriate modes, frequencies, sub-bands, and dedicated frequencies listed. Oddly, I was able to pass the US extra-class license without knowing or studying any of this. I believe I posted the story previously, but it's interesting enough to repeat again. I don't recall what year, but at the time, the FCC decided to drop the US Morse Code requirements. Since the technician class license consisted of the exact same technical questions as the general class license (element 3), it was decided that one could upgrade from technician to general without taking any additional tests and by simply paying a nominal processing fee. I arrived at the scheduled VEC exam session and presented my collection of expired licenses and forms as proof that I passed the technician class exam. Since I didn't need to pass an exam, I hadn't studied. I was then informed that I could take the extra class exam (element 4). If I failed, I would still get the general class license. Seemed like a reasonable thing to do. So, I took the extra class exam, totally and completely unprepared. I didn't even bring a calculator. Except for some creative wording in many of the questions, the technical parts were quite familiar and easy. However, element 4 also included some questions that required operating experience, such as band edges for the extra class only sub-bands, and similar questions. I did my best by guessing and was certain that I had failed the exam. Amazingly, I passed. So, if anyone asks if it is possible to pass the US extra class exam without knowing much about HF operating standards, I would answer that it might be possible. From my warped perspective, the ham license is NOT a demonstration of competence. It's simply the minimum one is expected to know so that they can operate a ham transmitter without breaking any rules, becoming a nuisance, or otherwise making a mess of the frequencies. One learns ham radio AFTER obtaining a license, not before. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#2
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#3
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On Sun, 14 Oct 2018, Jeff Liebermann wrote:
On Sun, 14 Oct 2018 08:50:13 +0000, Spike wrote: Stephen Thomas Cole, the PP, just after gaining his UK Full licence by 'acing' all three exams, appeared on a UK Amateur group asking which sideband he should use on 40m. That?s all you need to know about him and and his ability with radio. For what it's worth, I don't know which sideband to use on 40m. That's because I don't operate much on 40m and don't have such details memorized. I use a wall chart with the appropriate modes, frequencies, sub-bands, and dedicated frequencies listed. Oddly, I was able to pass the US extra-class license without knowing or studying any of this. I believe I posted the story previously, but it's interesting enough to repeat again. There was a time when SSB transceiver used mixing schemes so it would always be the "right" sideband when you switched bands. Even rigs that had a lsb/usb switch would sometimes color code so you knew which sideband was "right" for each band. I suspect more recent rigs, with synthesizers and computers, they surely default to the "right" sideband when you switch bands. As I recall, when I was a kid, I knew from reading which sideband got used on which band, SSB was hardly knew then but it was still "new" enough that it got talked about in the magazines. But with an SP-600 and a tuneable BFO, I had to tune the BFO both sides of zerobeat to figure out which worked for which sideband, no convenient crystal controlled BFO marked "lsb/usb". If there was a question on the tests about this sort of thing, it would likely show some frequencies and you'd have to figure out after heterodyning which sideband you were on. Michael |
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On Sun, 14 Oct 2018 18:50:34 +0100, Brian Morrison
wrote: On Sun, 14 Oct 2018 10:42:24 -0700 Jeff Liebermann wrote: For what it's worth, I don't know which sideband to use on 40m. For data modes it's just about all USB, and has been for some time. But it's easy to see why people can get confused and wonder what they set up incorrectly. No need to beat anyone up about it, just explain if you're asked. I don't think I'm beating up on anyone, but if an explanation is required, I can do that. It might help to understand why some bands use LSB while others USB. In the early daze of sideband radio, the common IF frequency was 9MHz. The radios had only one sideband filter. With one filter, it was cheaper and easier to mix and up convert in the transmitter. So, to save the cost of adding a second filter, the bands below 9MHz were designated as LSB and the band above 9MHz became USB. Eventually, radios were built with two sideband filters, and this was no longer important. As usual, the legacy technology remained in place to haunt the survivors to this day. The problem repeated itself with the rise of the digital modes. People wanted mult-band radios, but didn't want two filters in the radio. So, someone flipped a coin and decided that everything should be USB when using digital modes. For example, with JT65A, it's USB on all bands: http://hflink.com/jt65/ I'm not quite sure if that's also the case with other digital modes. For example, PSK31 (BPSK) doesn't care if you use USB or LSB, but by convention, USB is preferred. For marine radio HF communications, it's all USB. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#5
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On Sun, 14 Oct 2018, Jeff Liebermann wrote:
On Sun, 14 Oct 2018 18:50:34 +0100, Brian Morrison wrote: On Sun, 14 Oct 2018 10:42:24 -0700 Jeff Liebermann wrote: For what it's worth, I don't know which sideband to use on 40m. For data modes it's just about all USB, and has been for some time. But it's easy to see why people can get confused and wonder what they set up incorrectly. No need to beat anyone up about it, just explain if you're asked. I don't think I'm beating up on anyone, but if an explanation is required, I can do that. It might help to understand why some bands use LSB while others USB. In the early daze of sideband radio, the common IF frequency was 9MHz. The radios had only one sideband filter. With one filter, it was cheaper and easier to mix and up convert in the transmitter. So, to save the cost of adding a second filter, the bands below 9MHz were designated as LSB and the band above 9MHz became USB. Eventually, radios were built with two sideband filters, and this was no longer important. As usual, the legacy technology remained in place to haunt the survivors to this day. Actually with filter rigs, they used only one filter. Military rigs might use two filters, obviously especially if they did ISB, and there must have been some ham rigs, high end, that used two filters, but generally it was one, and the BFO crystal was switched. There's more to this story, but I can't remember at the moment. Michael |
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