[ARCHIVED THREAD] - HF/ham noobs -- example minimalist station pics attached -- post your questions here... (Page 2 of 2)
Thank you. The RG-8/U coax was given to me, but is in good shape, no nicks in the jacket. It is too stiff to make a choke balun. I just got some LMR-200 and a piece of 4" pvc pipe (Home Despot sells little cut off ends) so I will make the entire run from the dipole hanger, wrapped 17 turns around the pvc, and down into my shop all in one run with no other connectors or splices. So, that will complete it unless I find I need to add some 10 meter legs to the antenna if a tuner won't get the SWR down. Update! Done. And the antenna tuner I have now easily tunes this antenna on 80/75 meters, 40 meters (have not tried on 30 meters), 20 meters, 17 meters, 15 meters, 12 meters, 10 meters, 6 meters. It won't tune 160 meters.  Choke balun added. Difficult to see, but black Ty-wraps are used to keep the windings in place on the balun. LOTS of coax seal tape (gummy butyl rubber stuff) was used to keep moisture out of the connectors. Look up "Ugly Balun" via Google. Also, on top, 2m/70cm J-pole. The RG-8U was used to go to the J-pole. The middle conductor from the coax connects to the 19" stub. That 19" stub, along with the 55" rod, which connects to the coax shield, acts as a J-pole for 2 meters. The 19" stub, along with the 4 1/8" stub (which also connects to the coax shield) acts as a J-pole for 70 cm (440-450 mhz). |
ME: "I think I know why we're having trouble tuning on 80." OTHER GUY: "Oh? Why?" ME: "Someone plugged the tuner into the 2m socket." OTHER GUY: "Doh!"  Have to admit, I'm a little glad I wasn't the one... |
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Dang! I'm all dressed up and nowhere to go! Firmly in hand now:  (1) Antenna (as seen previously), now with new coax and choke balun, and (2) Yaesu FT-897 with (3) Yaesu FP-30 110 vac power supply installed and (4) LDG AT-897 automatic tuner screwed on the side, (5) LDG FT Meter, as well as the (6) Mic and (7) all necessary jumpers, cables, and widgets BUT (8) NO LICENSE! I've been cramming, doing the online tests, and now I'm consistently doing 95-100% on the online Tech practice exams. I'm consistently doing 82%-88% on the General exam. Found a Hamfest about 3 hours drive on the 11th. I was told, but have not had it confirmed, that I can take at least the Tech. I intend to take both at the same time if offered. Meanwhile, I'm going to keep up on the Tech questions and try to bring the General scores up to a more comfortable margin... well, really, I don't want to just scrape by. I want to actually learn the material. |
Good for you!... I have just started today gathering up info for the Extra exam. |
Good for both of you! A_Free_Man: The tech and general both seemed a fair bit easier in person than online. If you're consistently hitting 85% online you're all set, nothing to worry about. It's admirable to actually learn the material though. The extra, on the other hand, is quite a bit bigger challenge. Anyone can do it, no question, but I think they've done a decent job of making it hard enough that you have to really want it. Not many folks could cram for a weekend and walk out with a decent score without being lucky or very skilled (either at cramming or engineering). And most are happy enough with general privileges. A few weeks of diligent study, however, and a nice chunk of extra  bandwidth is yours for the chewing. The lower end of 40m (SSB) comes in handy at nighttime, especially, and there's a lot of DX at the lower end of 20m. LG. ETA: Wow, that's a pretty nice antenna setup. You obviously put a lot of thought into this beforehand and a lot of pride into a high-quality build. Best learning experience money can't buy. You're a shoe-in for general. You're clearly motivated and excited about what you're doing. |
use this --> abacus.nmsu.edu/~shoran/PDF/Tech_Course.pdf and use this --> abacus.nmsu.edu/~shoran/PDF/General_Course.pdf
use this --> abacus.nmsu.edu/~shoran/PDF/Extra_Course.pdf ar-jedi |
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Just heard back from the contact at the Hamfest. They'll be testing for all licenses, same $14 fee whether you take one or all three. Our local club president, a friend who is a VE (but lives several states away), and others, are all telling me to sit for all three tests. So... ROADTRIP!  |
Thanks, Gibson. That was put together for an Icom R75 I bought last spring. I've built various antennas for AM/MW, FM broadcast, WiFi, and other uses. I've built loops, tuned and untuned. But my main interest had been for audio gear. When I bought the R75 I wasn't getting quite the results I wanted with just a random wire, so a friend, and several of HIS friends in the local ham club helped me on that antenna project (photos bottom of p2 this thread). Then they encouraged me to get a ham license. I will say this, the ham community is VERY helpful. If you have any interest whatsoever, they'll darn sure give you all the help you could ask for. |
THANK YOU! And I had found this which was very helpful (better than the ARRL books, which are hard to slog through). www.w5ddl.org/techppt/index.htm These are Powerpoint classroom presentations for Tech. Brought my scores on the online tests up from 80-85% to 95-100%. I was looking for something similar for General, Thanks! |
Thanks, AR-Jedi... those were quite a help. I passed all three tests. I will soon be an Extra when the FCC gets me listed on ULS. |
If I understand this right you need to have an antenna as long as the wave length to get the signal right? 10 meter signal needs a 30+- ft antenna?? Can you use a yagi to direct the signal while running a 10 meter? Also how do these mobile rigs work on lets say 10 meter if they are running a short antenna on the vehicle? 
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If I understand this right you need to have an antenna as long as the wave length to get the signal right? 10 meter signal needs a 30+- ft antenna?? Can you use a yagi to direct the signal while running a 10 meter? Also how do these mobile rigs work on lets say 10 meter if they are running a short antenna on the vehicle?
Jagchaser, this is the Reader's Digest version. KISS. No, you don't need a full wavelength for the antenna. You need a HALF wavelength for a dipole. Why half and not whole? Because the half wave length radiates the positive half of the wave for 180 degrees, and then goes negative for 180 degrees. Or if a single element is used, it is only a quarter of a wavelength. A quarter wave single element is really half of a dipole. The other half is mirrored by the ground, ground plane, or by ground radials. For mobile, that means your car body. So, a 10 meter BAND dipole would only be 5 meters long TOTAL. It would have two legs, one connected to the center conductor of the coax, the other to the shield of the coax. And each leg would be 1/4 wave or 2.5 meters long. If it is a quarter wave vertical whip (which is what you will use on a vehicle), then it is 2.5 meters long. The other missing half of the dipole is mirrored by ground, ground radials (wires extending out from the antenna to form a ground plane), or if on a car, the car body. But 2.5 meters, even if attached to your bumper or trailer hitch, is still 8.2 feet tall, plus, say, another 2' from ground to base of antenna... over 10' tall. That will catch on your garage door and lots of other things as you drive around. That is not going to work. You can put a coil at the base, middle, or even tip of a whip to make it act electrically longer than it really is. "Base loaded whip", etc. This allows the quarter wave antenna to be made shorter that the theoretical length. It will tune to the frequency for which it is made, but won't have as good efficiency as if it were the actual length needed. Here's a quarterwave vertical with a coil in the center. 
(That's a photo of the popular "Buddistick") So, the 10 meter rigs work just like a CB antenna... CB is 11 meters (27-28 mhz), btw. A 10 meter antenna (28-30 mhz) is the same as a CB antenna, just shortened a little to work correctly (low SWR) at the 10 meter frequencies. And you've seen CB antennas that were not 8.7' long. They were only about 4' long. There was a plastic thingy at the base of the antenna, or maybe in the middle. That is the loading coil. But now you know why 2 meters is more popular for vehicles. A quarter wave vertical is only 19" long. Even for 6 meters, only 4.5' long... without a loading coil. |
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I have just started today gathering up info for the Extra exam. use this ––> abacus.nmsu.edu/~shoran/PDF/Extra_Course.pdf ar-jedi Thanks, This is great! |
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If I understand this right you need to have an antenna as long as the wave length to get the signal right? 10 meter signal needs a 30+- ft antenna?? Can you use a yagi to direct the signal while running a 10 meter? Also how do these mobile rigs work on lets say 10 meter if they are running a short antenna on the vehicle?
Jagchaser, this is the Reader's Digest version. KISS. No, you don't need a full wavelength for the antenna. You need a HALF wavelength for a dipole. Why half and not whole? Because the half wave length radiates the positive half of the wave for 180 degrees, and then goes negative for 180 degrees. Or if a single element is used, it is only a quarter of a wavelength. A quarter wave single element is really half of a dipole. The other half is mirrored by the ground, ground plane, or by ground radials. For mobile, that means your car body. So, a 10 meter BAND dipole would only be 5 meters long TOTAL. It would have two legs, one connected to the center conductor of the coax, the other to the shield of the coax. And each leg would be 1/4 wave or 2.5 meters long. If it is a quarter wave vertical whip (which is what you will use on a vehicle), then it is 2.5 meters long. The other missing half of the dipole is mirrored by ground, ground radials (wires extending out from the antenna to form a ground plane), or if on a car, the car body. But 2.5 meters, even if attached to your bumper or trailer hitch, is still 8.2 feet tall, plus, say, another 2' from ground to base of antenna... over 10' tall. That will catch on your garage door and lots of other things as you drive around. That is not going to work. You can put a coil at the base, middle, or even tip of a whip to make it act electrically longer than it really is. "Base loaded whip", etc. This allows the quarter wave antenna to be made shorter that the theoretical length. It will tune to the frequency for which it is made, but won't have as good efficiency as if it were the actual length needed. Here's a quarterwave vertical with a coil in the center. (That's a photo of the popular "Buddistick") So, the 10 meter rigs work just like a CB antenna... CB is 11 meters (27-28 mhz), btw. A 10 meter antenna (28-30 mhz) is the same as a CB antenna, just shortened a little to work correctly (low SWR) at the 10 meter frequencies. And you've seen CB antennas that were not 8.7' long. They were only about 4' long. There was a plastic thingy at the base of the antenna, or maybe in the middle. That is the loading coil. But now you know why 2 meters is more popular for vehicles. A quarter wave vertical is only 19" long. Even for 6 meters, only 4.5' long... without a loading coil. Excellent explanation! I'm still not sure if a vertical is better than a yagi, or if a yagi will even work on the 10-11 meter. So the only real difference between cb and 10 meter is Cb radios are normally less quality Cb radios are regulated at 4 watt max while 10 meters are higher So in theory if you had a 11 meter vertical antenna, equal watts, equal radio quality then you would get similar results +-?? |
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So the only real difference between cb and 10 meter is Cb radios are normally less quality Cb radios are regulated at 4 watt max while 10 meters are higher So in theory if you had a 11 meter vertical antenna, equal watts, equal radio quality then you would get similar results +-?? no. excerpts from Ham Radio 101 (tacked): http://www.ar15.com/forums/topic.html?b=10&f=22&t=604477 CB exists within the "HF" frequency range (~1MHz to 30MHz), as does amateur radio. CB is allocated, as you already know, a band right near 27MHz (~26.965 to ~27.405), and the amateur 10meter band is just slightly higher at around 28.0 - 29.7 MHz. All things being equal, a CB and and a 10m ham radio would have approximately the same range since they are both affected the same way by the ionosphere. But clearly there is something else different, something that gives one an advantage over the other... keep reading...
Power is one aspect of range, an important one –– but not the only one. As I discussed in the third or fourth post in this "Ham 101" thread, the way the audio is modulated onto the RF carrier is extremely influential on how easy or difficult it is to recover the audio at the other end. AM is one of the worst possible ways to transmit voice, and that's the type of modulation CB uses. AM, combined with only 4 watts output, is just not going to make it as far as a superior modulation method combined with more power. In contrast with AM, SSB is much much much (i can't emphasize this enough!) more efficient in terms of using the available power to greatest effect. Ergo, SSB, combined with the higher power available on ham rigs, allows for far greater communication distance at very nearly the same frequency as CB. So as you can see, it's not just about power.
(I would also like to point out here that the receiver section on a typical ham radio is miles ahead of the receiver section on a typical CB radio. You need to cut some pretty big corners in order to make a CB that sells for $50. A ham rig, on the other hand, is at a price point that allows for better components (oscillators, filters etc) and additional circuitry (especially DSP [digital signal processing]). If you look at the entire communications path from strictly a power perspective, there are two factors: how powerful the transmitter is and how sensitive the receiver is. Hence, you can improve range by increasing transmitter power and/or increasing receiver sensitivity. If you do both, you get a lot more range. This is the case with the higher power output and excellent receivers on ham radios. And we haven't even plugged in the benefit of using SSB modulation yet! remember, IT'S NOT JUST ABOUT POWER. Lots of hams use less than 10W to talk around the world. The art here is understanding propogation conditions, using the right modulation mode, driving a proper antenna, and having a good quiet (low noise floor) receiver. ar-jedi |
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I'm still not sure if a vertical is better than a yagi, or if a yagi will even work on the 10-11 meter.
for some applications one is better than the other, and vice versa. a "vertical" is a generic term for a vertically mounted antenna 1/4 wavelength high with a suitable groundplane underneath. as you learned from A_Free_Man above, in some cases special provisions are made at the base to either (1) electrically lengthen the antenna or (2) provide a matching section to a longer vertical element. hence, you can have a vertical which is somewhat shorter than 1/4 wavelength (see (1), allowing a "short" antenna) or a vertical which is longer than 1/4 wavelength (see (2), and a 1/2 wave radiator). in the case of a vertical 1/4 wavelength antenna on a suitable groundplane, the resulting pattern is omnidirectional (RF is emitted equally in all directions of the compass). moreover, the antenna is said to be "vertically polarized", which is a complicated way of saying that the RF field emitted by the antenna is vibrating up and down, not side to side. a yagi, or any other type of *directional* antenna, trades away the omnidirectional pattern for gain in one or more directions. for example, a yagi antenna is perfectly suited for making a point-to-point link between two fixed locations (e.g., a water level monitoring transponder at a damn and a central monitoring station some miles away). on the other hand a yagi antenna is a terrible match for use on a car; besides the physical size of the antenna, with every turn the vehicle makes the heading of the antenna would need readjustment to keep it pointed in the right direction. a yagi, and most other directional antennas, can also be mounted for vertical polarization (elements are vertical) or for horizontal polarization (elements are, well, you know, horizontal). there are certain advantages and disadvantages to each polarization mode. one benefit of vertical polarization at VHF frequencies is that it eases the mounting of antennas on vehicles (see the FM radio antenna on your car, and the antennas on public safety vehicles, etc). for optimum communications range at line-of-sight distances (e.g. terrestrial VHF/UHF operation), the transmitter and receiver antenna polarizations MUST match. on HF frequencies, when propagated via the ionosphere, matching the polarization mode of the antennas is not critical. ar-jedi |
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I have just started today gathering up info for the Extra exam. use this ––> abacus.nmsu.edu/~shoran/PDF/Extra_Course.pdf ar-jedi Thanks, This is great! Fuggin A! Right click, Save As! |
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So how did you manage to break the pictures?  i'm trying to convert my server at home from an old, static photo gallery system (webgallery, link) to a modern, scalable, feature-laden, PHP-coded, MySQL database-driven system (gallery 2.x, link) –– whilst keeping all of the existing links intact so i don't have to edit every picture URL in the Ham 101 FAQ, among other things. it is going swimmingly. 
ETA: check the time on this post. ar-jedi |