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LimeSDR

limemicro.com

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Re: LimeSDR

#31

Post by trothamel »

superkuh wrote: post #15
nlh wrote: post #14

I 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?

Not 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.

That'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=... ) makes to be useful for this .

You're probably not saving any money this way, but you do learn a lot.

Re: LimeSDR

#32

Post by opwieurposiu »

SDR 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.

Re: LimeSDR

#33

Post by syedkarim »

touisteur wrote: post #22
tzs wrote: post #17

The 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 t…

It 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 but I can't imagine the price will be very light-hobby-adapted.

We are shooting for a price of $299 for KrakenSDR.

Re: LimeSDR

#34

Post by platz »

stagger87 wrote: post #20
platz wrote: post #12

The 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

This 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

The issue is not with the chip itself, but with with the choices made for the board construction https://wiki.myriadrf.org/LimeSDR_HF_Performance

Re: LimeSDR

#35

Post by rtkwe »

tzs wrote: post #17

The 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 t…

It’s tough for small groups or hobbyists to do because building and keeping stock is a considerable investment and risk so a lot of times they’ll do batches constantly.

Also if you’ve had multiple projects that would want to use it why not order it knowing you’ll probably have a similar idea in the future?

Re: LimeSDR

#36

Post by syedkarim »

stagger87 wrote: post #23
birktj wrote: post #19

Earlier quoted context omitted.

This is probably true, meaning you can't really have a FCC certified tx-capable SDR. However in order to legally use the tx-capabilities of an SDR you probably have to be a ham anyway. And hams don't need their equipment to be FCC certified if I am not mistaken.

> However in order to legally use the tx-capabilities of an SDR you probably have to be a ham anyway. You can transmit in the ISM bands without a license. There are still power restrictions which most SDRs won't exceed anyways.

Yes, a general user/consumer can transmit in the ISM band without a license, but they are still required to use intentional transmitters which have been certified by the FCC.

Re: LimeSDR

#37

Post by ThrowawayR2 »

Blackthorn wrote: post #2

Does 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.

The 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.

Re: LimeSDR

#38

Post by CSSer »

WrtCdEvrydy wrote: post #26
atonse wrote: post #9

SDR 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 aro…

The best one is the ADS-B Out from airplanes, you can map the planes around you with a $20 widget.

This sounds really cool. When you say 'around you', what kind of radius are we talking?

Re: LimeSDR

#40

Post by rtkwe »

CSSer wrote: post #38
WrtCdEvrydy wrote: post #26

Earlier quoted context omitted.

The best one is the ADS-B Out from airplanes, you can map the planes around you with a $20 widget.

This sounds really cool. When you say 'around you', what kind of radius are we talking?

Hard 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?).
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