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Author Topic: SDR recommendation......  (Read 9051 times)

Offline Ray Lalleu

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Re: SDR recommendation......
« Reply #30 on: August 28, 2020, 0824 UTC »
There is this 16 bit SDR called RX888, and seems storming the SDR market recently.

https://swling.com/blog/2020/08/the-new-rx-888-16-bit-adc-direct-sampling-sdr-with-32-mhz-bandwidth/

Which software packages support it?

I have no idea, because it seems a new product from China. [....]

On swling, you can see a HDSDR screen (with RX888 control box).
On eBay, 'HDSDR' is in the product title and is mentioned in the detailed description as made compatible with the RX888 (waiting for other SDR software)
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Offline NJQA

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Re: SDR recommendation......
« Reply #31 on: September 06, 2020, 1455 UTC »
Copied from my rely in another thread....

The RX-666 and RX-888 are similar. Both are based on the BBRF103 open-source design. The RX-888 adds an integrated LNA, plus claims of possibly a higher-precision TXCO, for around $200 to $250 from China via eBay or similar.

For HF and below, both appears to use the LTC2208.... or a clone.... or a salvage chip? The LTC2208 is 15 years old at this point, but AFAIK, it still is not a cheap IC to legitimately source new. Up to 32MHz sampling, with up to 28.8MHz alias-free sampling. USB 3.0 is required for such high sample rates.

BTW, above HF they use a common R820T2, but apparently with up to 8MHz sampling currently possible.

----------------

About software, AFAIK there is a modified version of HDSDR+EXTIO for the RX-666, plus I have seen a claim the BBRF103 project EXTIO should work. I have no idea if either supports configuring the LNA in the RX-888, though.

More:
https://dk8ok.org/2020/09/04/rx-888-32-mhz-16bit-200-us-pricks-up-your-ears/

This is starting to look interesting.

Offline RobRich

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Re: SDR recommendation......
« Reply #32 on: September 06, 2020, 2202 UTC »
My personal interest still remains where the LTC2208 chip is being sourced to build a ~$200 SDR. o.0

Dynamic range aside, I am somewhat curious about image rejection and selectivity when trying to simultaneously sample ~32MHz of RF space with a SDR architecture designed to generate profit at a ~$200 price point, especially when a huge chunk of the production budget theoretically should be the LTC2208 chip alone.

Also I would consider VHF and above simply as an added bonus given those ranges are using a R820T2 chip, so up there think more along the lines of a RTL-SDR with a higher sampling rate via the USB 3 interface.
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Offline Jari Finland

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Re: SDR recommendation......
« Reply #33 on: October 09, 2020, 1455 UTC »
Since yesterday I have been an owner of RX-888. How proud, remains to be seen. Next comes, perhaps sooner than later, a real test and comparison with Perseus using 500-800 metres long beverages.

I wouldn't be so shocked about LTC2208. For example Digikey gives retail price of 100 USD or less.
https://www.digikey.com/en/products/filter/data-acquisition-analog-to-digital-converters-adc/700?s=N4IgTCBcDaIDIBUDCYwAYAcIC6BfIA

I can imagine a Chinese factory selling these straight from the line to another Chinese factory for half a price or less. You can construct a 200 USD SDR with that and make a little profit.

Personally I am curious about who is actually making these. We have now several SDR receivers designed and manufactured by hams: Belka, Malakhit. And this Chinese copy of Italian BBRF103.

Offline ChrisSmolinski

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Re: SDR recommendation......
« Reply #34 on: October 09, 2020, 1500 UTC »
I bit the bullet, and have a RX-888 on the way as well. Not sure when the slow boat from China will arrive, probably not for a few weeks. I'll report back with some test results when it does arrive.
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Offline Jari Finland

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Re: SDR recommendation......
« Reply #35 on: October 09, 2020, 1527 UTC »
Not sure when the slow boat from China will arrive

Mine was resting in Shenzhen for one full month before it began moving anywhere.