10 ms·
LimeSDR
- ehttwljlq34y 5y agoBiden needs to be removed immediately. He has murdered dozens of American citizens and was laughing about them yesterday. Fucking evil piece of shit.
- Blackthorn 5y agoDoes anyone know of a solution that can go down to the 5khz range? Older (...and even newer) gym equipment uses the gymlink protocol for heart rate monitors instead of low power Bluetooth and friends, and very few monitors support it anymore. I wanted to try to make a converter but couldn't find anything to output in that frequency.
- octopoc 5y agoI think it's pretty easy to make circuitry to shift a radio's frequency. If you did that with LimeSDR you'd still get the same bandwidth but it would be shifted into a different range.
- ronsor 5y agoAt 5000 Hz, you could probably just rig up a sound card with a mic input.
- Blackthorn 5y agoI need to output the 5khz, not input it. Would I be able to do that with a sound card in a small form factor? The idea is to have a small box that can convert my heart rate monitor to something that the gym equipment can understand.
- ronsor 5y agoI believe attaching an antenna to the card's output could work. For small form factor, a USB sound card and a Raspberry Pi is a possibility.
- jpindar 5y agoI've used a cell phone as an audio signal generator for testing transmitters. There are apps for sending a continuous signal, and I assume it would be easy enough to write one for sending a modulated signal. BTW, this is one reason why I won't buy a phone without an audio jack.
- jquast 5y agoHam It Plus can go upconvert as low as 300Hz, compatible with any SDR you just shift the frequency in software https://support.nooelec.com/hc/en-us/articles/360005812474 https://support.nooelec.com/hc/en-us/articles/360005812474
- Blackthorn 5y agoGuess I didn't make it clear and that's my bad. I need to output 5khz, not input. The input is a more modern Bluetooth protocol.
- jquast 5y agosorry maybe we misunderstand each other, I just got my license last year but this FAQ link reads, "Is the Ham It Up capable of transmitting as well as receiving? Even on lower frequencies? -- Yes, it is bidirectional, so you can transmit and receive on any frequency within range, provided that you have a compatible transceiver, like the HackRF One. "
- user-the-name 5y agoWhy not just use audio out then?
- ThrowawayR2 5y agoThe only thing I can think of that goes that low out of the box is the old Ettus Research USRP1, B100/B110, or E100/E110 SDRs combined with both a LFRX daughtercard and LFTX daughtercard, which are DC - 30 MHz. The SDRs themselves can occasionally be found on eBay and the daughtercards are still sold directly by Ettus Research or themselves occasionally can be occasionally found on eBay.
- moftz 5y ago5KHz is pretty low, it would be difficult finding anything in the ham category because no ham bands are that low. You would need to probably build your own receiver. The good news is that 5KHz is super low frequency and could easily be received with a crystal detector. Antenna connects to an LC resonator centered at 5.3KHz, pass the result of this through a diode and then into a microcontroller. Many have analog input pins and analog comparators built-in that can trigger an interrupt. You would need to figure out what voltage level you expect to see from the detector when a heart beat signal is sent and then apply that voltage to the other side of the comparator. Some microcontrollers even have a real analog voltage output that could allow you to adjust the voltage through software. The microcontroller would then trigger an interrupt and do something every time a heart beat signal is received (send it through serial to a PC, compute heart rate, display something on a LED screen, etc). If you need to broadcast at 5.3KHz, that's pretty easy too. There are numerous designs out there for a basic CW transmitter (https://makerf.com/posts/ten-minute-transmitter https://makerf.com/posts/ten-minute-transmitter). You may have trouble finding a crystal centered at your 5.3KHz frequency.
- lxe 5y agoTry an upconverter like this https://www.nooelec.com/store/ham-it-up.html https://www.nooelec.com/store/ham-it-up.html or https://airspy.com/spyverter-r2/ https://airspy.com/spyverter-r2/
- jmrm 5y agoI find totally rare that these devices works at 5kHz. instead of 5MHz or 500Khz (for example). At 5kHz you would need in theory huge antennas to being able to transmit and receive the signal correctly, and hundreds of kHz frequencies are totally achievable even with the most basics mid 1900s telecom systems. If you know the data to send, and you are totally sure the data is sent electromagnetically at 5kHz, you can modulate in as sound in a computer and play it in a PA system connected to a long cable,
- moftz 5y agoI haven't used a LimeSDR but I have used the mini version which is just about the same hardware minus the extra TX/RX channels. It's a great little device that covers a massive spectrum with a decent bandwidth as well. Comparable devices from Ettus are much more expensive. I'd love to own one for ham stuff but haven't had much time for that hobby lately. The Lime rep did give me a mini PCB on a keychain once, coolest trinket I've ever gotten at a conference.
- octopoc 5y agoOne of my concerns with using an SDR is that the FCC basically requires DRM[1]: > ...importers and marketers should ensure that [two-way radios] are properly certified and labeled as FCC-compliant and cannot be easily modified to operate outside its grant of certification. So if you use an SDR for LoRa, you have to make it hard for users to modify the code to emit a different frequency. [1]: https://docs.fcc.gov/public/attachments/DA-18-980A1.pdf https://docs.fcc.gov/public/attachments/DA-18-980A1.pdf
- stefan_ 5y agoBut this is a fully generic SDR. Can this even be certified as some consumer product?
- octopoc 5y agoI mean if you used an SDR in your consumer product. Let's say you make a dual purpose LoRa / WiFi radio to put in vehicles for a fleet management solution. If you use an SDR, you'd have to lock it down with DRM to prevent end users from repurposing it.
- rfdave 5y agoWell, it would also cost at least 10x what a dual purpose LoRA/WiFi radio would cost if it were built out of LoRa parts from Semtech and an ESP-32.
- stagger87 5y agoUsing an SDR for this kind of product would be horribly cost and time inefficient. You would design it with off the shelf WLAN and LoRa ICs. > If you use an SDR, you'd have to lock it down with DRM to prevent end users from repurposing it. Not any more so than a product you designed that didn't use an SDR as its core.
- stefan_ 5y agoYes, but the same applies to your WiFi router even if it has hardware filters. Its simply a certification requirement. That doesn't have anything to do with LimeSDR. This is already not a product that is certified for anything. It exists in a very gray zone where anyone using it for transmission is likely in violation of the law unless they obtained a development/testing license in the specific band they are using.
- atonse 5y agoSDR is one of those technologies I still want to play with that I feel will open up this incredible new world to my curious mind. All of a sudden, the invisible waves around us that we often tangentially know about but never think about (because we can't see, smell, or hear them), become a whole sixth sense to explore. I really hope for some free time to play with this, and to expose this invisible world to those around me (especially my kids), in a way that has been much less accessible in the past. Even things like ceiling fan remotes, door sensors, wifi, a garage remote, a car key, ISS video feeds, data from stuff in SPACE, weather data, I mean, we're bombarded with it every day all the time and we just don't realize it. Anyway, just had a wide-eyed moment, as I do every time I read about another thing that makes SDR just a bit easier to access.
- WrtCdEvrydy 5y agoThe best one is the ADS-B Out from airplanes, you can map the planes around you with a $20 widget.
- CSSer 5y agoThis sounds really cool. When you say 'around you', what kind of radius are we talking?
- rtkwe 5y agoHard to answer that it depends on so much; the quality of the rx you're using, the antenna and your local environment (open field? wooded area? valley? top of a hill?).
- sosborn 5y agoIt really depends on the environment around you. I live deep in valley, so my range is pretty limited to line of sight.
- ambientenv 5y agoYou may be able to find out more information, including instructions on assembling your own ground station, at Flightaware - https://flightaware.com/adsb/piaware/build/ https://flightaware.com/adsb/piaware/build/
- platz 5y agoThe multichannel components LimeSDR used are more constructed for streaming video applications, but they dont have good sensitivity in the HF range. I wish I had gotten a hackRf instead, which also had better tooling support
- stagger87 5y agoThis doesn't seem right, you might be thinking of a different product. The LimeSDR uses the LMS7002 IC as an all in one dual channel RF to bits chip. The chip specifically is targeting broadband wireless communications applications. Data sheet linked below. https://github.com/myriadrf/LMS7002M-docs https://github.com/myriadrf/LMS7002M-docs
- platz 5y agoThe issue is not with the chip itself, but with with the choices made for the board construction https://wiki.myriadrf.org/LimeSDR_HF_Performance https://wiki.myriadrf.org/LimeSDR_HF_Performance
- stagger87 5y agoI was more specifically responding to your comment that it was constructed for "streaming video applications". I don't think the SDR is targeting this application.
- nlh 5y agoI was super into the ham world many many moons ago (DE K2KD), and my curiosity is definitely piqued with the arrival of SDRs. Dumb question(s): Is it possible to do "traditional" HF/VHF ham stuff with these mini SDRs? Is there a good software package that emulates the old-school rigs (but with fancy new features)? Are these radios powerful enough to drive an amp to get to something like 100W (or 1500W) on HF?
- superkuh 5y agoNot without paying a bunch for bandpass filters and power amps to get it up high enough to actually drive your 100w amp. Most SDRs are just the transceiver without all the front-end parts you really need for a "usable" radio.
- jacquesm 5y agoYes, true, you'll need a bunch of intermediary stage amps as well, you won't drive 100W without something in the middle. Typically a set of usable stages would be an SDR, a very sharp bandpass filter, a 1W or so buffer, then something on the order of 5 to 10W and then into real power stages 50-100 or so and if you want to go substantially higher than that you'll need yet another stage. And each of those will need to be perfectly regulated to avoid dumping a bunch of harmonics into the air.
- trothamel 5y agoThat's correct, though getting those is possible, and something of a fun project. I've found the stuff 60dbmco ( https://www.ebay.com/sch/60dbmco/m.html?_nkw=&_armrs=1&_ipg=&_from= https://www.ebay.com/sch/60dbmco/m.html?_nkw=&_armrs=1&_ipg=... ) makes to be useful for this . You're probably not saving any money this way, but you do learn a lot.
- jacquesm 5y agoBefore you start pumping out that kind of power I'd invest in a spectrum analyzer (which are surprisingly affordable today) to ensure that the signal that goes out is clean. Those mini SDRs when used for transmission will output a ton of harmonics because they are almost by definition not going to have any filtering on their output because that would limit their usability. When used for reception that is not a problem, if you start using them for transmission it's a completely different matter. Keep in mind that a power stage that responds well to a particular signal absent filtering is going to respond quite well to the main harmonics too!
- tzs 5y agoThe couple of times I've had something I wanted to do that needed an SDR more powerful than than an RTL-SDR and decided I wanted a LimeSDR or LimeSDR mini...the lead time on them has been such that it would not arrive in time for the project I wanted it for. Right now, both LimeSDR and LimeSDR mini orders place now don't ship until Feb 28 2022, except for the LimeSDR PCIe which ships Sep 29 2021. (You might be able to get the USB LimeSDR sooner from Sparkfun. They say they might have some coming in early October). Projects where I'll need something like that are rare enough that I can't really justifying buying one just in case another such project comes up.
- touisteur 5y agoIt is very depressing indeed. Has eBay or second hand given good results on this to anyone? I guess we'll have to wait for https://www.crowdsupply.com/krakenrf/krakensdr https://www.crowdsupply.com/krakenrf/krakensdr but I can't imagine the price will be very light-hobby-adapted.
- syedkarim 5y agoWe are shooting for a price of $299 for KrakenSDR.
- touisteur 5y agoOh thanks for your answer, that's very interesting! For someone wanting to upgrade from rtl-sdr that seems a good step up. While you're here, I'm particularly interested whether you're aiming for something more ambitious some day or 100% focused on kraken? I'm thinking coherent 32/64 rx channels or more? Also, is there a way to assemble two krakens and synchronize them somehow so as to have 10x coherent rx? :-) There's probably a better channel of communication for such questions ... Thanks again for jumping in with a correction.
- syedkarim 5y agoWe have plans to offer a few different versions of KrakenSDR. The entry level version will likely be the current version with 5 tuners. We are laying out an idea for 8 tuners, integrated CPU, and pre-set antennas; basically a turnkey system for remote operations. We can definitely produce more exotic beasts, but I don't think there is much of a market for a Kraken with a hundred heads.
- cepher 5y agoDoes anyone know if this is more appropriate than the PlutoSDR for hobbyists? Seems like they have similar specs and are around the same price.
- ohazi 5y agoI haven't played with the Pluto, but I do have a USRP, which uses the Analog Devices front-end, and it's leagues more reliable than the LimeSDR. I would absolutely go for the Pluto if it'll work for your application. I guess the main limitation is USB2 for getting the captured signal out, so you wouldn't be able to use it for crazy high bandwidth applications.
- opwieurposiu 5y agoSDR made me understand how much RF noise my desktop computer emits. Lots of spikes between 400-500mhz. Could be my monitor also, as scrolling text seems to emit the most noise.
- themodelplumber 5y agoSame here with the monitor, I have an old Dell 24" from 2006 that I somehow keep around. I've learned not to expect much if my ham radio is within 3 feet of it. Probably fixable with some clip-on parts but for now it's easier to scoot the chair over...
- tzs 5y agoMy Samsung monitor does that. It's bad enough that I lose several channels on my Samsung TV when my Samsung monitor is on if the TV antenna is in the same room as the monitor.
- jareklupinski 5y agointeresting... I guess I never scrolled while looking at wideband noise :) I'm going to see if I can determine what is/was displayed on the screen by filtering/machine learning the noise, fingers crossed
- cschneid 5y agoThere's a fun toy I just got called 'TinySA' (tiny spectrum analyzer). For $60, plus an adapter + some wire (another $20 maybe), you can get a live battery powered little receiver that shows noise across the whole spectrum from less than 1mhz through 350mhz. A really basic loop of wire is a directional antenna, so you can narrow down exactly what is causing issues too. I'm doing it to find noise issues for my ham radio setup, but it can be generally fun. Not quite an SDR, but to find noise sources it's pretty amazing for so cheap.
- madengr 5y agoYeah, now PC come in damned glass cases. So much for the FCC.
- marcodiego 5y agoLTE, GSM... Does it means it is now easier to build an entirely free device that can be used as a cellphone?
- themodelplumber 5y agoYou mean with proper licensing? That might be the tricky part; use of the rf spectrum is probably monitored and regulated, depending on where you're at in the world.
- amelius 5y agoNo WiFi support?
- rfdave 5y agoWiFi is hard to support, it's very complex from a signal processing and timing perspective.
- amelius 5y agoAnd probably also the protocol.
- the_only_law 5y agoI mean you have to pay way to much money just to look at the specs (or settle for an older one that’s a pain in the ass to find for some reason)
- nuand 5y agoWifi is a pretty difficult protocol, but fortunately Linux ships with mac80211. So all that is needed is an SDR based PHY such as https://github.com/Nuand/bladeRF-wiphy/ https://github.com/Nuand/bladeRF-wiphy/ .
- rektide 5y agostill havent used mine. supposedly theres not as much software thats ready for limesdr, that this is a mire rareified pick than many ither options.
- IshKebab 5y agoI got a LimeSDR when they first made them. Unfortunately the whole SDR software ecosystem is pretty terrible. Even with something as popular and widely supported as RTL-SDR most of the software is unusuable (with some happy exceptions). It also doesn't help that there is an absolute mountain of SDR software out there, but 99% of it is "this is cool, I'm going to write... eh nevermind" type stuff. There's so much ( https://www.rtl-sdr.com/big-list-rtl-sdr-supported-software/ https://www.rtl-sdr.com/big-list-rtl-sdr-supported-software/ ) that I can't even find the one good one I found last time I used an RTL-SDR. I guess that is what happens if you play with software written by uber-nerds for uber-nerds. Anyway in conclusion I would NOT recommend getting a LimeSDR unless you are really really into SDR and it's your only hobby, or better yet, your job.
- platz 5y agoas an early limesdr buyer i completely agree
- jandrese 5y agoThe LimeSDR Kickstarter made these grand promises of running a repo full of usable apps for your board. Many years later that repo is still quite spartan. I've generally had pretty good luck with my LimeSDR, but I don't try to push it too hard. The documentation can be frustratingly minimal in so many places and the USB implementation on my board is touchy (it must be plugged into exactly the right port on my computer or the device enumerates incorrectly and is unusable).
- dang 5y agoSome past related threads: Investigating the Galileo Satellite Navigation System Outage with a LimeSDR - https://news.ycombinator.com/item?id=20464852 https://news.ycombinator.com/item?id=20464852 - July 2019 (41 comments) LimeSDR Now Backed by the European Space Agency - https://news.ycombinator.com/item?id=16493727 https://news.ycombinator.com/item?id=16493727 - March 2018 (38 comments) LimeSDR Mini – An open, full-duplex, USB stick radio for femtocells and more - https://news.ycombinator.com/item?id=15318233 https://news.ycombinator.com/item?id=15318233 - Sept 2017 (46 comments) LimeSDR funded, some hours left to still get a discounted SDR - https://news.ycombinator.com/item?id=11946239 https://news.ycombinator.com/item?id=11946239 - June 2016 (10 comments) LimeSDR GSM Base Station Demo - https://news.ycombinator.com/item?id=11931072 https://news.ycombinator.com/item?id=11931072 - June 2016 (27 comments) IoT wireless hacking – LoRa on the LimeSDR - https://news.ycombinator.com/item?id=11882491 https://news.ycombinator.com/item?id=11882491 - June 2016 (1 comment) Digital Video Transmission using LimeSDR and GNU Radio - https://news.ycombinator.com/item?id=11856912 https://news.ycombinator.com/item?id=11856912 - June 2016 (8 comments) LimeSDR: Flexible, Next-Generation, Open Source Software Defined Radio - https://news.ycombinator.com/item?id=11610521 https://news.ycombinator.com/item?id=11610521 - May 2016 (28 comments)
- ohazi 5y agoI wish them luck, but judging by the ~week I spent trying to get a LimeSDR mini to work, their product is so half baked that it's basically not fit for purpose, and if you're considering getting one, I'd recommend something with an Analog Devices front-end instead. The PLL would fail to lock at random frequencies and temperatures. You'd try to scroll through e.g. the 2.4 GHz ISM band and would randomly get downconverted signal or baseband noise on every other click. Two minutes later, the set of bands you could capture would be entirely different. There was no consistency whatsoever. When I went to their forums to see if other people had encountered the same issue, it turned out that basically none of the LimeSDRs even pass their own self tests [1]. I don't know how they're still selling these devices... they don't work. I returned it, paid ~4x more for a USRP, and could not be happier. The hobby is playing with radio modulation schemes, not debugging a defective piece of silicon. [1] https://discourse.myriadrf.org/t/new-limesdr-mini-loopback-test-failed/6067/2 https://discourse.myriadrf.org/t/new-limesdr-mini-loopback-t...
- Prcmaker 5y agoUnfortunately, I agree with this. I was an early backer on the mini, and got it with the aluminium case. While the case looked great, it mechanically interfered with the antennae, meaning they didn't actually make a connection. Their support taught me how to screw in an antenna, ignoring the actual problem, before deciding my issue was too hard and ignoring me. I got eventually got in some antennae from Ossmann, but when other hardware/software issues cropped up, my enthusiasm for the device had already waned too much to want to put in effort. I got some basic things working eventually, but never outperformed cheaper devices.
- tibbon 5y agoI've got the LimeSDR standard size one, and I've never been able to make good use of it. Thinking of throwing it on eBay soon. Software support is far more limited than I'd prefer compared to other SDRs too, which someone at DEF CON told me was because they pissed off the community and copied of a lot of things from another SDR project. I don't know how true it is, but I can see that support on all sides is pretty half baked.
- 5y ago
- benbojangles 5y agoI would suggest using limesdr mini with sdrangel. Lots of people working on using them for digital TV station transmition.
- ngz00 5y agoAny suggestions on where to start to use this as a LTE uplink that reads from an SD card and uploads images? I'd like to replace my expensive faulty game camera subscription.
- myself248 5y agoUsing an SDR is the most painful and power-hungry way to replicate what already exists as cheap, optimized, small, commodity LTE modems. Use the SDR for standards that don't exist as finished silicon yet.
- themulticaster 5y agoIn addition to what myself248 said: In case you aren't familiar with the details of consumer RF standards (including IEEE 802.11, but especially LTE or anything cellular related) or don't have some prior RF knowledge: To put it mildly, LTE is not an easy standard to implement on an SDR, especially if it's your contact with SDRs. Even GSM is nowhere near a simple stack. If you want to get a feeling for what kind of cellular projects are possible using SDRs from a hobbyist/free software perspective, have a look at the Osmocom (Open Source Mobile Communications) projects [1] as well as Harald Welte's blog [2] (one of the main Osmocom contributors). The Osmocom projects are focused on the carrier side of LTE/GSM networks AFAIK. Another warning: While cellular technology involves lots of networks, it is completely different from the standards and terminology used in the Internet. For example, citing the description for OsmoHNBGW: "An Open Source implementation of a HNB-GW (HomeNodeB-Gateway), implementing the Iuh, IuCS and IuPS interfaces. It aggregates the Iuh links from femtocells (hNodeBs) and presents them as regular IuCS and IuPS towards MSC and SGSN (such as OsmoMSC and OsmoSGSN). It uses M3UA as signaling transport." The description totally makes sense to an insider, but if you only dabbled with TCP/IP, routers and switches so far, be prepared for learning a whole new world of networking terms. If you are familiar with RF/cellular engineering and/or if you're trying to do this on a corporate budget then you probably already know what I mentioned above, and your project can certainly be realized for $$$. If you're looking for a one-off DIY solution then you could use something like a u-blox SARA-R4 [3] modem (for NB-IoT/low bandwidth). Similar boards with higher bandwidth also exist. [1] https://osmocom.org/projects https://osmocom.org/projects [2] https://laforge.gnumonks.org/blog/ https://laforge.gnumonks.org/blog/ [3] https://www.sparkfun.com/products/14997 https://www.sparkfun.com/products/14997
- easton_s 5y agohttps://www.drti.com/ https://www.drti.com/ https://web.archive.org/web/20161106083817/http://www.drti.com/catalog/software-defined-radio/ https://web.archive.org/web/20161106083817/http://www.drti.c... The true master of SDR....
- rfdave 5y agoOne of many Govt focused RF companies. Start from Watkins Johnson and look at the spinoffs, although they've mostly absorbed into Bigger defense contractors at this point Boeing bought DRT in '07? This site has a good history http://blackradios.terryo.org/index.html http://blackradios.terryo.org/index.html
- unwiredben 5y agoI've got a LimeSDR Mini. I mainly use it as an ATSC 1.0 signal generator from time to time for testing TV tuner code at work, and it does a good job, as long as I'm running it on a PC with a high-bandwidth USB 3.0 port. I've had issues going through hubs.