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Post by Joey on Nov 18, 2016 22:19:10 GMT 10
So how far can one reach on 10w say on 80,40,15,2m and 70cm?
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paranoia
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Post by paranoia on Nov 18, 2016 22:56:25 GMT 10
So how far can one reach on 10w say on 80,40,15,2m and 70cm? Thats an amazingly complicated question that depends on everything from time of day, how urban you are, height of antenna, style of antenna, how many sunspots there are at the time... Different wavelengths open and close depending on the solar weather. Not talking LOS propagation for these long distances but skipping off the ionosphere... I'll spend a bit of time attempting to quantify what do expect. But anecdotally I've been told by people that would know you can talk to other countries at night using 10w HF. I guess what we need to determine would be reliable distances based on simple low gain antennas with modest setups. Will attempt to lock somthing down.
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Ammo9
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Post by Ammo9 on Nov 18, 2016 23:00:15 GMT 10
Haven't heard of the cows trailers. Its 4 hours from the nearest staff station which I'm fairly sure doesn't have a cons trailer of any sort or 6 hours from most of them. That's a quarter of a day before a trailer gets here at a minimum. A lot can go down in 6 hours. Assuming my organisation has them
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shinester
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Post by shinester on Nov 19, 2016 2:35:26 GMT 10
So... Couple issues with the numbers there. On a foundation licence your maximum output power is 10watts, this is peak and silence between your words takes no power to transmit, medium volume is half power, ect. I'd double that number to take efficiencies of the radio into play but this is still minimal compared to the 100w listed. If power is an issue I would be running a manual antenna tuner over an auto one which does not need extra power (there are slight efficiency losses but these are minimal) Cant fault your RX numbers except to say I'd think you would set aside a few hours in the evening for coms rather than having your station on all the time. Fair enough. Have you got an approximate daily consumption then? I'm also curious from your comments before about 1-2 hrs drive away, is that using repeaters? Even with directional antenna that seems like an extraordinary distance for handhelds, I presume we need a rather tall antenna/hill? Makes me want to go get/make a yaga now.
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Post by Joey on Nov 19, 2016 3:09:50 GMT 10
OK para, assume a budget antenna setup (loop) no fancy gear, average day average weather conditions average sun spots etc
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VegHead
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Post by VegHead on Nov 19, 2016 7:29:45 GMT 10
I had typed a very lengthy response to your numbers post Shiney, but the post disappeared into the ether somehow.
Suffice to say, most of your numbers are incorrect. I ran a 100w rig and very large Auto tune Antenna from a standard car, trickle charged battery for four years, Txing twice a day. We are only looking at10W Tx here at far less than 100% modulation. A SLA battery could manage that (if interested look up a Q Mac HF90, discontinued about 6 years ago.These were 55w and ran off SLAs).
I'm not trying to complicate things here, I'm trying to simplify them. Also, most of us here I think are looking at base rigs not portable, but with portable being vehicle mounted, so our power reqs would be quite different. There is also another reason I mentioned the FT450, a hidden capability, but that would be for an offline discussion only...
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Post by graynomad on Nov 19, 2016 8:13:35 GMT 10
Following this, and I'd love to get HF/HAM and participate in a network of some kind, but no way I can afford this kit at this point.
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paranoia
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Post by paranoia on Nov 19, 2016 8:15:27 GMT 10
So... Couple issues with the numbers there. On a foundation licence your maximum output power is 10watts, this is peak and silence between your words takes no power to transmit, medium volume is half power, ect. I'd double that number to take efficiencies of the radio into play but this is still minimal compared to the 100w listed. If power is an issue I would be running a manual antenna tuner over an auto one which does not need extra power (there are slight efficiency losses but these are minimal) Cant fault your RX numbers except to say I'd think you would set aside a few hours in the evening for coms rather than having your station on all the time. Fair enough. Have you got an approximate daily consumption then? I'm also curious from your comments before about 1-2 hrs drive away, is that using repeaters? Even with directional antenna that seems like an extraordinary distance for handhelds, I presume we need a rather tall antenna/hill? Makes me want to go get/make a yaga now. I was thinking using a mobile CB rig, from a quick search around looks like antenna gains of 12-16dB on CB yagi are quite achievable. Which is a gain factor of 16-32, for a 5W unit thats 80-160 watt equilivant. The rest is all terrain dependant. We used to do a similar thing back in the day with wifi before fast internet was achievable. A wifi probe in a peach juice can does amazing this but is super directional and takes a little fiddling with. Height definately helps but you can also find a refraction point if you have a mountain between you. Waves will bend around corners (think wave slit expirement) and this can be exploited in cirtain situations.
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VegHead
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Post by VegHead on Nov 19, 2016 8:36:51 GMT 10
Following this, and I'd love to get HF/HAM and participate in a network of some kind, but no way I can afford this kit at this point. For you situation Gray an antenna can be made from what you probably already have laying around, and if 'cut' correctly would not need a tuner. Also, you could have several of these and still not need an external tuner as you can switch between the bands.
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VegHead
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Post by VegHead on Nov 19, 2016 8:40:53 GMT 10
paranoia the quoted Rx power reqs are given for rigs with everything turned up to max, including the displays. Do you really need your front end RFA on full bottle all the time for example?
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Post by Joey on Nov 19, 2016 8:44:01 GMT 10
How large can one make a loop array ? Could on utilise a existing string wore fence say on a rural property and take the torture and insulate it at each pole and so forth make a giant look?'
Also how many would be interested in a yaesu FT-450?
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shinester
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Post by shinester on Nov 19, 2016 8:58:43 GMT 10
Thanks for the corrections. The power requirements you're suggesting very much put it back to portable. Sorry to make you type left handed veg. The more you guys chat the more I'm liking the idea.
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paranoia
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Post by paranoia on Nov 19, 2016 9:07:24 GMT 10
paranoia the quoted Rx power reqs are given for rigs with everything turned up to max, including the displays. Do you really need your front end RFA on full bottle all the time for example? Good point! You can also be careful in your choice of radio as to not have digital screens and illuminated displays.
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paranoia
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Post by paranoia on Nov 19, 2016 9:10:09 GMT 10
? Could on utilise a existing string wore fence say on a rural property and take the torture and insulate it at each pole and so forth make a giant look?' I raised this idea at the club and it was told to me that I risk building a Yagi. If the other wires in the fence resonated you would either send your signal into space or the ground...
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VegHead
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Post by VegHead on Nov 19, 2016 9:27:23 GMT 10
Simple long wire Joey .... Or a rhombic lol.
I'll say it again. Do NOT think of loops for HF TX. The closest to a loop is the cubicle quad, not my idea of being discreet, and even at ten metres amateur band they are huge.
The world of RF is a tricky one, and it doesn't 'play' like normal ac current. One's head can truly be done in by it!
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VegHead
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Post by VegHead on Nov 19, 2016 9:43:21 GMT 10
? Could on utilise a existing string wore fence say on a rural property and take the torture and insulate it at each pole and so forth make a giant look?' I raised this idea at the club and it was told to me that I risk building a Yagi. If the other wires in the fence resonated you would either send your signal into space or the ground... Correct when transmitting at higher powers but the the reverse can also be true when receiving only.... You CAN amplify the signal seen by the transmission line and gain an advantage that way. However I think we are all trying to run before we can walk. KISS remember?
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VegHead
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Post by VegHead on Nov 19, 2016 9:45:27 GMT 10
Thanks for the corrections. The power requirements you're suggesting very much put it back to portable. Sorry to make you type left handed veg. The more you guys chat the more I'm liking the idea. The typing is not as bad as having to live how I do with one wing out of action!
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shinester
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Post by shinester on Nov 19, 2016 10:44:43 GMT 10
The world of RF is a tricky one, and it doesn't 'play' like normal ac current. One's head can truly be done in by it! Phew, I thought it was just me.
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Post by graynomad on Nov 19, 2016 12:47:19 GMT 10
Following this, and I'd love to get HF/HAM and participate in a network of some kind, but no way I can afford this kit at this point. For you situation Gray an antenna can be made from what you probably already have laying around, and if 'cut' correctly would not need a tuner. Also, you could have several of these and still not need an external tuner as you can switch between the bands. OK, it's still academic for now though if the radios cost $500...or even $100
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Post by graynomad on Nov 19, 2016 12:48:24 GMT 10
The world of RF is a tricky one, and it doesn't 'play' like normal ac current. One's head can truly be done in by it! Phew, I thought it was just me. I can probably claim to be an expert in some areas of electronics, but RF? Forget it, that's a total black art.
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