LimeSDR

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NYG

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Jun 9, 2006
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I was following that discussion because I did get in on the early bird discount. I do see that there is a fairly easy mod to open things up on the HF bands.
 

deadite66

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Jul 31, 2016
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Perhaps but having to hardware mod a $300 device isn't what most people would expect.
 

mehdi_asgari

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Jun 22, 2015
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LimeSDR is more of a development board than a commercial single purpose device and it's not an uncommon thing to have some faults here and there in the initial versions. The mod is not that hard to do, but I'm sure they will fix it in the next release.
 

dsalomon

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FYI..

They WILL give a refund if you ask.

I emailed them yesterday asking for a refund. Their reply was that they are working on the problem and should have a fix shortly. They offered a refund, or asked if I wanted to wait until they announced their fix. They also said that they have stopped shipping while they work on the issue.

I chose to wait.

If they do resolve the issue and the result is true wideband performance (i.e. they don't fix HF and break everything else), then I'll proceed with the order. In that case, I'll report back here with results when I get mine.

Best and 73 - David, AG4F
 

dsalomon

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They sent out that update yesterday to all the Lime backers with the info about removing the inductor to restore HF.

Here is a link to a long thread discussing modification of the Lime, including multiple different modification approaches. It provides 2 "easy fixes" that consist of removing either one inductor or one inductor and one capacitor, and a third modification consisting of changing the value of four components (3 capacitors and two inductors), which provides "broadband (100KHz - 400MHz)".

In their update / email, they offered to do the "easyfix1" modification to existing or to be shipped boards for a limited time. The user must fill out a form prior to Feb 21, 2017 to be eligible. This is not a long term offer, i.e. after Feb 21, no further modification requests will be accepted (this according to their blog / email). They also offered (again) to refund the purchase for those who desired it.

The post also contains graphs of performance for unmodified and each of the modifications. My interpretation of the graph is that "easyfix2" gives the best results with minimal effort (removing 2 components). It has a slight performance dip at around 300KHz compared to the nroadband approach. However, the rest of the curve shows better performance than the other approaches. This is the modification I will do to my board.

I would also look at the "Return Loss and VSWR for Broadband Match" graph. It clearly shows that there is a relatively high loss with the Broadband Match (-12db) at frequencies up to about 500MHz.

Even with the easyfixes, the signal is at -80db at 1MHz with a 45dbFS test input. At 100Khz it's -100dbFS. So, you must realize that if your ambient noise level is above -100dbFS to -80db, you still won't hear anything. My advice: measure your ambient noise level with another radio (SDR or otherwise) to check your noise level. If it's higher than -100dbFS to -80dbFS, and you want good HF performance, look elsewhere. If you don't have an HF radio, get a friend to bring one over to your shack to measure. IMHO, it's a worthwhile simple test to perform to avoid disappointment.

73 - David, AG4F
 

jaguarundi

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Feb 22, 2017
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Has anyone got one yet? Just like to know how it's working, etc. And @J9G I too wonder what the beta testers were doing. In that thread mentioned above there was at least one beta tester that just recently started to make noise about HF freqs. and they had the device for a year or so.
 
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