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LimeSDR

limemicro.com

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Re: LimeSDR

#11

Post by Blackthorn »

jquast wrote: post #8
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.

Ham 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

Guess 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.

Re: LimeSDR

#12

Post by platz »

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

Re: LimeSDR

#13

Post by Blackthorn »

ronsor wrote: post #6
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.

At 5000 Hz, you could probably just rig up a sound card with a mic input.

I 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.

Re: LimeSDR

#14

Post by nlh »

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?

Re: LimeSDR

#15

Post by superkuh »

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.

Re: LimeSDR

#16

Post by octopoc »

stefan_ wrote: post #10
octopoc wrote: post #7

One 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/publ…

But this is a fully generic SDR. Can this even be certified as some consumer product?

I 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.

Re: LimeSDR

#17

Post by tzs »

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 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.

Re: LimeSDR

#18

Post by jquast »

Blackthorn wrote: post #11
jquast wrote: post #8

Earlier quoted context omitted.

Ham 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

Guess 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.

sorry 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. "

Re: LimeSDR

#19

Post by birktj »

octopoc wrote: post #7

One 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/publ…

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.

Re: LimeSDR

#20

Post by stagger87 »

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

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