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eHam Forums / Misc / RE: In the age of "virtual technical parity" Do Specs matter anymore?
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on: March 13, 2013, 03:14:05 PM
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Many years ago (almost 50!), as a young development engineer, I was told 'There are no prizes for vastly exceeding the specification'. It proved to be partially true in that case, as specs written for one technology didnt apply to another.....But it's a good start to a philosophy.
You must not have worked for a audiophile-level amplifier company! 
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eHam Forums / Misc / RE: In the age of "virtual technical parity" Do Specs matter anymore?
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on: March 12, 2013, 03:33:03 AM
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The other question is, will the population support a company that takes a chance on a radical new design? The IF DSP was a no-brainer, but I remember a lot of complaining about audio DSP being inferior to other filtering techniques. But we had to get audio DSP to prove the concept and get some R&D started on how to improve it, which led to IF DSP.
SDRs are generally in the same boat. Look over in the QRP forum to see a very long debate over the merits of the KX-3 vs the FT-817. The KX-3 is a very popular radio, and a great leap forward in shrinking technology, but there doesn't seem to be enough of an improvement for a consensus. Why is the Flex radio still a niche product if it is so much better? It can't all be the way the company is run.
I think many people look at Moore's law and try to apply it to everything. While it does lead to innovation in just about all technological areas, physics and economics will grind innovation to a halt once you get past the silicon chip level. Why don't we have direct-sampling SDRs? The technology exists and has for some time now. Well, because the chips and real-time processing power are still at a price point that is too high for most amateurs.
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94
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eHam Forums / Antenna Restrictions / Keeping RF out of the living space
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on: March 11, 2013, 06:31:22 AM
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I'm planning on installing my trusty old AEA ISOloop in the attic, along with a vertical 2M/70CM co-linear. It will be about 18' above the floor of the house, and I intend to run all network, phone and TV coax in the crawl space. This will be similar to a setup I had years ago when renting (although I had a balcony and no restrictions on outside antennas at the time), so I'm familiar with some of the compromises and issues that come up. When I was renting I always had a heck of a time keeping RF out of my stereo, especially the powered subwoofer. In the new place there's a couple of metal vent pipes and a gas fireplace flue going through the attic. The ISOLoop will only handle 100Watts and I don't really have any plans on increasing power down the road (although I might add a 40/80 meter loop and or a 6 meter dipole at some point). I plan on grounding all antennas and coax the same as if they were installed outside, all bonded to the electrical ground.
Should I also plan on grounding the various vent pipes? What about shielding the floor of the attic with something like chicken wire (grounded as well)? While I don't think there's going to be any major problems, I'd just like to avoid any minor inconveniences down the road.
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95
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eHam Forums / Misc / RE: Any homeopaths in the house?
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on: March 06, 2013, 04:51:35 PM
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This is what he's up against (2nd hit on Google search for "homeopathy and radio frequency radiation"): http://www.naturalhealingpro.com/radiation-x.htmlFrom the advertisement: Cell Towers • Cell Towers that are SENDING information are the harmful ones. • Cell Towers that are RECEIVING information are harmless. • If you have a cell tower near your residence or your office, find out if it is sending or receiving microwaves. $42.00 seems reasonable for peace of mind.
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96
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eHam Forums / Elmers / RE: contester vs ragchewer vs prepper
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on: March 04, 2013, 05:50:47 AM
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Experimenter: Try anything once, but when the "mission is accomplished" move on to something else.
Builder: Likes technology, but the last thing he wants to do is actually get on air and engage in a QSO, except maybe for testing.
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97
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eHam Forums / Digital / RE: 802.11 Use?
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on: March 02, 2013, 08:03:35 AM
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I've seen some articles from a group in Texas running a wide area network on modified 802.11 gear. Google can't seem to find the link now.
Our club president asked me to look into setting up an 802.11(x) link between our tower site and a club member's home (and on to the Internet). First thing I asked was "what for?" The answer was "whatever." Needless to say, it's a low priority.
I think it came up because another member asked about putting a web camera on the tower and suggested using a Verizon 4G card to transmit. I overheard the conversation and reminded the member that we already had more spectrum than Verizon, available for the hardware cost, much of which sits idle.
While I would love to see high speed networks interconnecting our repeater sites sans wired infrastructure, the truth is setting up this stuff isn't easy or cheap if you want reliable. It also gets difficult because most of the long-haul (>40 miles) equipment and protocols aren't designed for ham radio and our requirements for ID and other issues. A cell phone tower can transmit a constant QAM or other carrier for timing and other purposes, which isn't permitted under our rules. This makes syncing radios difficult and greatly increases turn-around time on transceivers. Until there's a real "killer app" for high data rate networks, I think we're stuck with going the other direction (low speed, very low bandwidth, low SNR) communications.
As for the legalities of running 802.11 protocols on 2.4GHz, we're the primary user of the band, so everyone else (theoretically) has to accept any interference we produce. As long as you don't encrypt and use your callsign in the SSID you're good to go.
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98
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eHam Forums / Station Building / RE: Amateur transmit audio equalizer software
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on: February 27, 2013, 12:47:34 PM
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Have you checked over in the reviews section? http://www.eham.net/reviews/detail/4860It looks good, one thing to caution you on with most DSP systems is delay and other problems, especially when processors are bogged down with a lot of tasks. If you're watching price, a good place to look for audio equipment is the local pawnshops. Bands are always forming and breaking up, and some fairly decent (better than you'll ever need for ham radio) gear can be had for little money. I recently picked up a used 2 channel compressor/limiter for $50, and it works just great. Another recent find is a very clean Chinese large-diaphragm mic for $100.
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eHam Forums / Antennas and Towers and more / RE: commscope F11 cable.
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on: February 27, 2013, 12:23:49 PM
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When I did outside line work if I found a bad underground cable that I wasn't able to dig up it would usually be temped with RG-11 until the construction crew could get it replaced. CATV hardline usually has 90 VAC running over it at up to 15A and I've never had any problems with it, other than a higher voltage drop than with .625 hardline coax.
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100
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eHam Forums / Antenna Restrictions / RE: Hidden antenna options ?
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on: February 25, 2013, 09:24:47 PM
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But the neighbor feeds the local squirrels on top of the fence, so I'm considering ways to discourage them.
A pellet gun will discourage them permanently. Or a 44 magnum  At almost $0.70/round that's an expensive way to get rid of vermin. And you'd better be a fairly good shot, too.
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eHam Forums / Station Building / Desk working height.
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on: February 20, 2013, 01:06:23 PM
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I'm going to be moving to a new QTH in a few weeks, and have the opportunity to set up a real ham shack. Right now I'm not very active, but the plan is to begin to build a multi-use station that may see some contest or DX activity. Given that contesting especially will require a lot of time at the radio, I'm thinking of building a station desk that's fairly high and using a barstool for a chair. That way I could also switch off and stand from time to time without having to make big adjustments. I got the idea from seeing commercial radio stations, many of which will allow DJs to stand or sit depending on their preference.
Anyone else have this sort of setup? What are the pros and cons?
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103
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eHam Forums / Antennas and Towers and more / RE: Antenna suggestions
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on: February 20, 2013, 11:48:15 AM
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MFJ magnetic loop and a 6 meter dipole will get you close, but not down to 80 meters. While checking out SGC's web site I noticed some of their manual show a loop configuration for their tuners. http://sgcworld.com/Publications/Manuals/stealthman.pdf might be an interesting read. Not recommending some of the configurations they have shown, but it should give you some ideas at least. Maglooops are a pain if you spend a lot of time jumping around, but for narrow data modes like PSK 31 where you might sit on the same band/frequency all day they work fairly well. I used an old AEA Isoloop for a while in my old apartment, set up on the balcony. Since I moved to a building that doesn't lend itself to masts or tripods, I now use a wire vertical in a tree that works about the same.
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eHam Forums / HomeBrew / RE: Read frequency of tuning fork on counter
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on: February 19, 2013, 03:19:01 PM
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or wind a coil around the tuning fork, hook it to the freq counter, strike the fork and hold it to a magnet. if there is enough wire, you can get enough voltage to feed the counter's chips.
the reverse was used in the 30s for master clock timing in radio. General Radio had an oven-mounted tuning fork driven with big-boned triodes that output 115 volts at exactly 60 cycles to power clocks. the triodes ran magnets that vibrated the fork.
Also the basic theory of operation for an Accutron watch. Later adapted by Seiko for the Pulsar quartz watch that is used by nearly everyone today.
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eHam Forums / Computers And Software / RE: I HATE Ubuntu 12.04 !
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on: February 19, 2013, 03:09:25 PM
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Slight change of topic, but anyone see the announcement of the Ubuntu Tablet? http://arstechnica.com/gadgets/2013/02/ubuntu-for-tablets-arriving-on-nexus-7-nexus-10-this-week/I loaded up the "beta" of this on my Nexus 7 (although it was more like straight Unity a few months ago), and was surprised to find FLDIGI, HAMLIB and other ham related software in the software center. The downside is that there was no optimization for a tablet environment on any of the ham programs, but at least Canonical thought to recompile everything they've always had when they created the repository. It was hardly stable, and I didn't attempt any rig control, but if they come up with an easy SDK and simple way to port applications it might lead to a tablet OS that will actually be useful for ham radio applications. (note the hand waving "maybe"s and "might"s. What can I say, I'm an optimist) 
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