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fuzzy_bunny's Achievements


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  1. Perhaps he meant soldering SMT is an art, which even if it doesn't qualify to go into an art exhibit, at least it does require some degree of skill and steadiness in the hands. High skill in anything is an art form, and some of the Chinese boards I have seen have shown the opposite side of the spectrum ( really, really, _bad_ connections and style ), as well as some that have been as well produced as anything I find made in the West. Sometimes the most apparently simple things are also paradoxically the most difficult to do well, although as far as soldering goes, I have been doing it long enough that I pretty much take my own ( admittedly craftsmanship laden ) work as a matter of course, as I also take my own humility for granted. -FuzzyBunny
  2. Don't use acid core solder. For ease of use, lead based solder is easier to work with, but has been banned in the EU. Using the environmentally friendly ( 99-1? ) solder requires higher temperatures, and is in general, harder to work with without damaging the board or components than using lead based solder, which works at a lower temperatures. As for lead being an environmental hazard as it is used on PCB's... eh, whatever. If the EU says so, it must be true. -FuzzyBunny
  3. My general rule of thumb is, if it is too hot to hold with your hand, or betwixt you forefinger and thumb, it is running too hot. One way to cool it off to some extent is to get it away from your computer or desktop, possibly dangling in mid air, with a USB extension cable. The more surface area that is exposed to the air, and the more cool air (as opposed to desktop PC exhaust) the more heat it will dissipate. Get one and see what you think. -FuzzyBunny
  4. In the Realtek 2838/820 combinations I have tested ( I have three ), it doesn't seem to matter much what size they are. The only thing I might be concerned about with something that small is that heat dissipation may be problematic. The only other concern I might have is that with a smaller board like it has, there would be less room for other surface mount components ( possibly filters ), which may help in noise reduction and boosting SNR ( Signal to Noise Ratio ) on the larger units. If you end up getting one, let us know what results you get from it. -FuzzyBunny
  5. I acquired a Realtek 2838 USB SDR with the Fitipower FC0013 tuner chip. I have to say... what a piece of excrement. The rf gain is less than half of that available in the Realtek 820 tuner, and station quality, both audio and digital across FM Broadcast and VHF is completely lackluster. I think in this case, the problem is with the tuner chip, as all the other different branded Realtek 2838 USB SDR's with the Realtek 820 tuners seem to perform pretty much the same. I don't have an E4000 tuner chip model to test, but the Fitipower dongle will likely end up at the bottom of a packing box, as I don't even think it is worthwhile to put it in the bottom of a desk drawer. I may end up mailing it to Hak5, if Darren or Shannon are interested in seeing it/having it/playing around with a tuner other than a Realtek 820. Who knows, maybe Evil Server will be able to mind meld with it and get something productive out of it's rather pitiful design. -FuzzyBunny
  6. Well, the "cable"/feed line betwixt the antenna and the card is just a wire, so if you are overly concerned about the frequency precision of the antenna, I could see this as being valid, if the wire were unshielded or unbalanced, or the distances were really long ( like electrical transmission/distribution lines, where line resistance, "skinning effect", and other considerations need to be taken into account to preserve power from unnecessary line loss, but here we are talking about hundreds of miles ( Transmission ) or < 100 miles ( distribution ) of electrical power ). In short wave listening ( almost a dead art form ) using a long unshielded/unbalanced piece of wire is frequently used, even though it isn't tuned to a particular frequency. Also, the longer the wire, the higher you can get your antenna, and in picking up radio broadcasts, the higher the elevation betwixt the top of the antenna and the level of ground is generally almost 100% of the time, a bonus. Radio waves get absorbed by the ground, buildings, ( metal siding ), so the longer the wire/feed line, the more likely you can get both higher and/or closer to the window. Shielded/balanced feed lines are also somewhat different from single conductor antenna wires, so we must be mindful of the difference betwixt these two designs/mediums. Professional radio stations don't use tall towers because they look pretty, they use them because they broadcast the signal over more obstacles ( and because of the power being used ). Short wave broadcasting arrays ( such as Voice of America/US AFRTS faciliities in Westchester, OH ) use many very long, heavy gauge antenna arrays oriented in different directions for their various broadcast destinations ( tuned for the wavelengths they are broadcasting on ). Ham radio operators, who have a choice in the matter, don't use a short feed line to receive from, and a long feed line to broadcast from, they try to get their antenna as high as possible. Generally, the higher the altitude the better, or if indoors, the closer to a window, the better. Obviously, receiving a signal we are dealing with just a small portion of the power we are dealing with when we broadcast, and the signal is already "in the air" from the tall transmission tower, so reception antennas tend to be shorter on portable receivers ( automotive based, or handheld ) as a matter of practicality, not really efficiency. Base stations ( transceivers ) still use long feed lines to their antenna towers, because they perform better at higher altitudes. A difference also exists betwixt receiving a signal at 88 MC/s vs 2.4 GC/s, so it really depends on your environment and the pluses you are trying to get at ( altitude, or proximity to a window ) vs the minus of the length of your antenna feed line ( interference on a long feed line usually comes from EMI/RFI rather than the resistance of the wire or the practicality of having a long antenna ). For your WiFi, you really don't want your signal going too far outside your house ( generally ) as you are trying to not conflict with others' use of the same spectrum space, and avoid them conflicting with yours, ( Part 15 FCC rules ) so the objectives are somewhat different, and the wavelength determines the optimum size of the omni's. When you are attempting to receive distant signals, the objectives and ways to achieve those objectives are completely different. The resistance in your typical copper wire is pretty negligible for the length of spans we are talking about, so having a short feed line isn't going to assist with signal strength as much as having the antenna placed somewhere free of obstacles and as high as possible. Also important is the characteristic properties of the signals we are dealing with, and whether we are depending on bouncing our signal off of the ionosphere ( or some people have bounced their radio transmissions off the moon... ), or whether we are dealing with more of a "short haul" transmission/reception objective, such as FM Broadcast Radio. -FuzzyBunny
  7. These are the specs of the antenna, but I am still testing and comparing it to the base antenna included in the Hak5 kit. I will post my results when I composit more data and observations. The length of the antenna cable also seems to help a bit. ( Ham technical description: long piece of wire ) Although it suggests using it with car/mobile applications, but I have found it functional for base station operations as well. Enhance the signal strength, reception and picture quality - Integrated 25dB low noise amplifier - Magnetic based mounting make DVB-T Antenna be placed much easier - High gain amplifier, ideal for DVB-T Digital Terrestrial TV Receiver - Super easy to install, no drilling required, put it on the car roof or above the - trunk with its magnetic base, fits almost every cars - Portable DVB-T Antenna is removable, therefore, also convenient to set while washing your car and in the three-D parking area - Frequency: VHF (174~230 MHz) & UHF (470-862MHz) - Signal Amplification: approx.25dB - Radiation: Omni - SWR: 1.5:1 (Max.) - Cable length: 195cm -FuzzyBunny
  8. I got the following from usd.dx.com, and I am pleased with the performance boost they provide, although I am judging based upon an ad hoc evaluation of signal strength of FM radio streams. Obviously, no antenna is perfect for every frequency, although the composite dipole antennas seem to provide good performance at wide bandwidth/wide variety of frequencies, but look like a throw back to the TV antennas everyone used in the 70's and basically, before Satellite and cable tv service was the defacto standard. However, the gauge of the wire, and the overall construction of the antenna I bought seems to be a big step up from the antenna included with the dongle, for the frequencies I am looking at. Here are links to the antenna I am playing with: http://usd.dx.com/product/portable-digital-dvb-t-tv-25dbi-omni-magnetic-based-aerial-booster-antenna-iec-901030061#.UydkzfldVOI To connect it to the Realtek dongle from the Hak5 store, you will also need: http://usd.dx.com/product/lwj-023-mcx-male-to-tv-female-antenna-adapter-cable-black-17-5cm-901207418#.UydmkfldVOI The antenna has a nice large base, and is beefier in size than the included antenna in the realtek dongle packs, and it seems to perform well for a general purpose Omni. Oh yes, the base is magnetic, so make sure you don't leave it on those vintage 5 1/4" floppies you have laying around. It, even with the adapter cable, is cheap, and this is usually a consideration for most of us. usd.dx.com also offers free shipping if you are willing to be somewhat patient. Everything you order from them arrives... eventually ( 1 1/2 to 2 weeks delivery is typical ). I almost hate to say it, but there are also Realtek dongles that have the larger antenna connectors built into the dongle, so you don't need the adapter cable if you are using a variant ( from another source ) of the Realtek dongle from the Hak5 store. Maybe the Hak5 store will start offering the other dongles with a more general/larger antenna connector. Signal is everything with radio. So, every connector/adapter you throw into the mix is going to drop signal strength a bit, especially when you drop the gauge of the conductor ( wire ) down. I understand the argument for the Hak5 dongle, you don't need to worry as much about position or it getting in the way of another usb Cable, but I just use a short USB extension cable. Having a cable in betwixt the dongle and the computer is completely different from strangling the signal strength coming into the dongle. Once RF makes it into the dongle, everything is USB/digital out to the port on your computer. Having the radio slightly away from the main body of the computer also has some benefits ( with the Hak5 dongle included in this mix ) as the location of the dongle away from the computer allows the dongle to not be blocked by the body of your computer ( if you are using a desktop ) which can have negative effects, also possible is RF interference from the computer, so my general opinion is the dongle works better off of an USB extension cable, but I use a lot of desktops, because the performance of desktops and the peripherals are in a form factor that makes modifications/maintenance much easier, and Notebooks are designed with battery life as a major consideration, so with less power, comes the consequence of less performance. I use a mix of desktops and laptops/netbooks/android devices, but the smaller form factor devices are mainly used for browsing and SSH or RDP'ing into my other servers/workstations, or other applications where mobility is more useful. My desktops are where I do most of my linux/FreeBSD/Solaris server or development/programming boxes, and my gaming.and Windows 7. One of my netbooks ( Intel Atom ) runs a nice linux distribution specifically designed for it, with a desktop that is oriented towards the smaller screen size. The others run Windows 7. Usually, if I am programming or doing things on the Linux/FreeBSD/Solaris boxes, I use RDP or ssh from a windows 7 box unless I need higher graphics/audio performance, then I do it on directly from the console of the host machine. I used the atom running linux for many years for most of my web browsing before I went to my dual core AMD netbook. The atom runs cooler and longer on the battery, the AMD cranks out the heat, but also has a nice bit of performance and can even limp along in most games. More heat from the computer means more performance. The netbooks are also convenient for working with microcontrollers, as far as programming them. I work with both Pic and Atmel microcontrollers, and a netbook is more appropriate for updating the code, especially when the microcontroller is already deployed in an application. ISP on Atmels pretty much means you need to drag the computer to where the microcontroller is doing its thing. The pics I use are socket oriented, and I can pop them out and drag them back to my Olimex Pic programmer. I don't debate which is better, as far as Pic vs Atmel. It is sort of like Apple vs Windows. I just don't care. I use whatever is best for the project. I have seen some people try to claim that newer computers are more environmentally sensitive, but in my experience, the more heat a computer cranks out, the better the performance. I also used to support data centres, so I have a bit of experience in power consumption, performance, and cooling issues. If you aren't familiar with HVAC/cooling issues with computer servers, you aren't working in a data centre that even qualifies as small scale, or you are running servers in Alaska. I have rambled, and I apologise for some of this, but I have learned so much about computers, electronics, programming, and networking that my mental wiring is partially fried, so consider anything I write as a partial core dump from my main CPU. When I went to school, I was usually kicked out from the computer classes and told to go work in the library on my projects, and just turn in the work at the end of the day, or the end of the quarter. Teachers found my breadth of knowledge to be intimidating, and my social skills to be largely undeveloped. I couldn't help it if I knew more than my teachers, with the exception of my coworker at Heritage College who was the head of the Computer Science department. He is a smart cookie, and was quite enjoyable to collaborate with, as well as learn from. Come to think of it, he was the only computer prof I had that didn't kick me out of his classes. -FuzzyBunny
  9. Just for grins and giggles, I compared the speed of processing in software the demodulation that we do in hardware in a traditional radio. There is a small delay, but I am going to guess that it is on the order of 1/10th to 1/20th of a second betwixt the audio coming out of a traditional radio to the output of an SDR setup with a ~$20 or less dongle. For someone who was brought up on 2 Mhz 48K byte computers, this is just freaking amazing. I remember, for the aforementioned specs of the Atari 800, it took every ounce of processing power, including turning off the video chip (about a 20% boost in performance), and everything the poor little thing had to render a 2-3 second clip of the Kinks "You really got me now", and even then, it was a far cry from broadcast or cd quality audio. In retrospect, I should have forecast some of the capabilities of modern computers and modern networks. Realistically, networks have become part of our computer systems. Without a network to stream information from the web or your video server to your ROKU or XBMC pc, the capabilities of our computational power is very limited. The amount of collaboration and innovation that even the community of Hak5 is able to produce through the web site and the weekly I-casts is nothing short of amazing. People from all over the country, or the world, are able to work together, with only language being a barrier, but increasingly, the web is making the world speak English. This trumps every social influence that people or cultures may claim. They may have localized languages, but the web speaks English, and English's place as a world language is all but guaranteed by computer networks, the Internet, specifically. I realise that TCP/IP cares nothing about the human language it transports, but as the innovation in networks and computer science is mainly a product of the US and our economic allies in Japan, Taiwan, China, and the EU, and RFC's ( the backbone of internet/TCP/IP innovation ) are written and distributed in English, I pretty much see English as being the uber-language of the future. My forefathers/mothers spoke German, Norwegian, English ( British English ), etc., but by the fourth or fifth generation, the only thing that matters is old traditional recipes made on the holidays. The rest of the culture has been absorbed. So will it be with our newest immigrants. So it will be with the world as they get absorbed into the world wide web. Many cultures, such as the Japanese and the Chinese and various Jewish and Moslem countries will always preserve their neighbourhood tongues... But they will also speak English, and speaking in English will become the international standard of communication through the influence of Internet Anarchy. If tracked back far enough, the Roman Empire is still alive and well, but wearing different clothes. It is more of something that we all take for granted. Roads ( arguably, an early network, still important in conjunction with the information network ), indoor plumbing ( arguably, an early crap network, sort of like Facebook ), bridges ( ok, more network analogies... ) our calendar and hours, our numerals, all have Roman origins. This is similar to how I perceive English's role in the future, something taken for granted, that people don't even think about. I hope I have not offended anyone. If I have, please accept my semi humble apologies. I don't intentionally try to offend anyone. It seems, like sarcasm, to be a natural talent I possess. -Fuzzy Bunny
  10. I have found the software to be a little buggy, but it seems we are on the bleeding edge of the development of support for the rtl DVB dongles. In any case, I have found that the definitions in sdr radio version 2 to be a little temperamental. If you have any problems, like with your rfgain knob not working, or no sound at all, go into the radio definitions and delete them, and then recreate them with the scan option (rtl_tcp option), making sure you correct the frequencies, as I get a default of 0-30Mhz quite often, and this is not really all that accurate for the rtl 2383 radios or the 820 tuner. So select better values, double check the port to make sure it is 1234, and then you should be back in business. I expect, as drivers and software evolves for these, that some of the bugginess will be going away, and error recovery should be more prevalent. -FB
  11. God, try administering Solaris and Sun workstations and mainframes for 10 years, AS400's, PDP 11's, Prime Hosts, linux, freebsd, netbsd, HPUX, DOS 2, Seattle DOS, OS/2, CP/M, and MP/M for 20 years previous to that. Consider yourself fortunate. I learned so much, I get PTSD episodes, and have been disabled for 9 years. Not being in the meat grinder of an IT Department has helped my functioning immensely, but I still avoid crowds, people, loud or repetitive noises, etc.. It is possible to learn so much your head explodes, or you have a mild to severe breakdown, chronic insomnia, hallucinations, etc. Enjoy computer and electronic technology and have fun. My best recommendation to anyone is just to have fun doing what you love to do. If you get squeezed too hard, quit. Eventually your doctors will tell you when you are done, as in a fried egg on a sidewalk in Arizona. -Fuzzy Bunny
  12. If anyone needs the user guide for this program, when you start the program, in the select radio dialog, in the lower right corner, is a blue hyperlink ( named, "Users Guide" ) that poops out a pdf user's guide to the program. -FB
  13. Oh, found the rf gain control in the gui, it is under the [Home] tab of the menu bar at the top. RF Gain is set to AGC ( Automatic Gain Control ) by default, but you can change it to any value your dongle supports. It is an icon that looks like a knob, third in from the right, in the box labeled Options ( in the grey bar at the bottom of the box ). Hope that helps. -Fuzzy Bunny
  14. Here is a cool SDR tranceiver almost out in production: To operate on most bands, you would need a ham (FCC) license in the US or an OfCom ( http://www.ofcom.org.uk/ ) license in the UK. It is cool to window shop and gaze at, however. http://ecom.eladit.com/FDM-DUO-1/en Since this box transmits on a wide range of frequencies, unlike the realtek dongles, these can get you in a _LOT_ of trouble if you use them in a band you are not licensed for. -Fuzzy Bunny
  15. According to sdr_tcp, which is running in a terminal/console, the gain mode is set to 0 ( either really 0, or mode 0 means agc automatic gain control? ). When I defined the radio in version two of the software, I just accepted the options for the gain options, which started at 0 and continued with about 15 or so values after that. In order to get intelligible sound, the first task in reviewing an application, I had more of a problem with the bandwidth of the signal it was decoding. That was what I was addressing in the second part of my instructions. Documentation on v2 is a bit on the spotty side. The web site assures me that the info is all here: http://v2.sdr-radio.com/Support/Settings.aspx Somewhere. Probably in the definition of the radio, you can set the gain manually (my best guess) and to get back to that value, you have to stop the software (v2, not rtl_tcp), and then click on select under favorites on the menu bar (positionally it is visually under favorites, you don't click favorites to get there, ie. it isn't a submenu of favorites). There you will see the definition of your rtl_tcp radio, and to the right, are the gain values. Highlight it and select edit to edit your radio definition, and here it appears you can set the gain. There may be another menu/slider to get to it, but that is the best answer I can come up with, having just installed this and gotten this running this evening. Hope that helps, best of luck. Cheers! -Fuzzy Bunny
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