Posted: 12/2/2013 10:40:31 AM EDT
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I am interested in trying out ham. I'd like to get the baofang radio that I see for $40 or so. I have a few questions about line of sight range I'd be able to get with that radio or a HT one similar to it. I would be willing to add a better antenna to it but for now I don't have alot of money to put into this.
I'd like to know if I'd be able to reach the closest repeater to me is which is 1.4 miles away as the crow flies. I live in a pretty built up suburb. I have looked at a topographic map and I am about 70 feet above sealevel and the repeater is at about 100. There are not any significant hills between me and the repeater but the ground has houses and shopping centers on it. When I read about radios being line of sight I am trying to get an idea on how literal that concept is. A second range question is about reaching a friend of mine's house which is 800 yds as the crow flies. His house is about 40 feet lower then mine. If you went straight from my house to his on a topographical map it looks like there are no hills. However just looking down my street I can see a hill that is 20-40 higher then my house that is maybe 100 yds to the side of a direct line of sight to his house. I am wondering if this hill would block the signal of a HT radio. Sorry if these questions seem really stupid. If it this is something you have to try to get an answer let me know. I don't want to spend any money just to find out that I need alot more gear just an HT unit to try out ham. |
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The 800 yard link should be doable even with the the hill and the Baofang with its stock antenna.
The repeater also sounds doable. In either case even a very basic antenna upgrade will make both solid connections. I was readable on my j-pole to about a mile to a friend simplex in a vehicle. Now go study for your test! 
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seems you should be fine w/ both scenarios. i can reach repeaters over 8 miles away from inside my house w/ stock antenna on my Baofeng. i live down by the sea, about 2 feet ASL. that particular repeater is ~100' or so ASL.
as far as Baofeng to Baofeng, 800 yards should be doable. all of the above is illegal, though, if you have no ham license. if you transmit w/out a license, my understanding is that retired, heavyset grey-haired hams will track you down, & find you, using their magical radio nerd skillz. then, may God have mercy on your soul....  
Quoted:
I am interested in trying out ham. I'd like to get the baofang radio that I see for $40 or so. I have a few questions about line of sight range I'd be able to get with that radio or a HT one similar to it. I would be willing to add a better antenna to it but for now I don't have alot of money to put into this. I'd like to know if I'd be able to reach the closest repeater to me is which is 1.4 miles away as the crow flies. I live in a pretty built up suburb. I have looked at a topographic map and I am about 70 feet above sealevel and the repeater is at about 100. There are not any significant hills between me and the repeater but the ground has houses and shopping centers on it. When I read about radios being line of sight I am trying to get an idea on how literal that concept is. A second range question is about reaching a friend of mine's house which is 800 yds as the crow flies. His house is about 40 feet lower then mine. If you went straight from my house to his on a topographical map it looks like there are no hills. However just looking down my street I can see a hill that is 20-40 higher then my house that is maybe 100 yds to the side of a direct line of sight to his house. I am wondering if this hill would block the signal of a HT radio. Sorry if these questions seem really stupid. If it this is something you have to try to get an answer let me know. I don't want to spend any money just to find out that I need alot more gear just an HT unit to try out ham. |
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For normal construction you'll probably be OK with both. Biggest caveat I can think of is if there is any significant amount of metal or concrete blocking the signal there could be some exceptions.
But hang up an inexpensive roll-up antenna (or home-built slim jim or j-pole) near a window or outside and you may even be able to use low power. A roll-up and some coax will be priceless if you find yourself in a situation where conditions are bad and you want to get out further. Even a cheap mag mount on a refrigerator or large barbeque will often work well if you're going to use it in your vehicle. |
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You should have no problem hitting either, even with the stock antenna. It doesn't sound like you're in a mountainous area and those elevation changes are nothing.
As to line of sight in general: You could easily hit the space station with the stock setup. In theory, the moon too. 
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Quoted:
As to line of sight in general: You could easily hit the space station with the stock setup. In theory, the moon too. The free space path loss to the moon is about 187 dB at 146 MHz. A transmitter gain of 37 dBm (5 watts) plus a receiver gain of 123 dB gets you 160 dB. So you'd need at least 27 dB of antenna gain.
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as others have said, you're probably OK.
Of interest is a line of sight calculator: http://easycalculation.com/physics/electromagnetism/vhf-uhf-distance.php assuming your antenna is 5' above ground level, and the repeater is on a 50' tower (most will be higher), your line of sight is 13 miles. Can you get 13miles with 5w from the stock UV-5R antenna? Maybe, but as also noted, cheap antenna upgrades make this less questionable. Buildings and hills in the way (as also noted above) depend on composition of the obstruction. Different materials absorb RF differently. |
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Thanks for the replies guys.
I have messed around with a bunch of the online line of sight calculators, but what gets me is they are all for a theoretic perfectly empty earth. Like you were in the desert or on top of a body of water. I was thinking that houses, trees, power and phone lines, street lights, etc might significantly reduce the numbers the calculators gave me. I am sure the do reduce your signal but the question is how much? Plus the repeater I said was 1.4 miles away, judging from the map, must be in someone's yard or on their house. So it can't be very high. |
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Quoted:
When I read about radios being line of sight I am trying to get an idea on how literal that concept is. The 2 meter band is located between the FM broadcast band (88 MHz to 108 MHz) and the VHF-high television band (174 MHz through 216 MHz), so it propagates in a similar fashion. The 70 centimeter band is located below the UHF television band (470 MHz through 698 MHz), so it propagates in a similar fashion. Some obstructions reflect signals, while other obstructions absorb signals. I found a fairly good (but technical) writeup on this here: http://en.wikipedia.org/wiki/Non-line-of-sight_propagation 800 yards HT to HT and 1.4 miles HT to repeater shouldn't be a problem. |