In case you have issues with Dropbox:

 

32-bit: https://1drv.ms/u/s!AovWaZDu7HrdzlF8cr3VvLRQN5tu

64-bit: https://1drv.ms/u/s!AovWaZDu7HrdzlJ7XS01VIaDUrA3

 

Simon Brown, G4ELI
http://sdr-radio.com

 

From: sdr-radio-com@... [mailto:sdr-radio-com@...]
Sent: 30 April 2017 21:37
To: sdr-radio-com@...
Subject: [sdr-radio-com] Not Preview 6 (Kit Enclosed)

 

 

So,

 

Before I make preview 6 here’s a little something, I just want to be sure it doesnR 17;t explode before I update my website.

 

Sorry I don’t have a list of what’s new etc., but recently:

 

• 64-bit uses CUDA 8 (you don’t have to do anything)
• Fixed quite a few bugs in the satellite tracking
• Added scheduled recordings
• Added a funky FM Stereo display

 

So, are you feeling lucky?

 

64-bit: https://www.dropbox.com/s/yur9idcy8xe1f7c/SDR-Radio%20V3%2C%2064-bit%2 C%202017-04-30_1928.exe?dl=0

32-bit: https://www.dropbox.com/s/jom0nf0gfmlhfow/SDR-Radio%20V3%2C%2032-bit%2C%202017-04-30_1930.exe?dl=0

 

Simon Brown, G4ELI
http://sdr-radio.com

 

64-bit: https://www.dropbox.com/s/yur9idcy8xe1f7c/SDR-Radio%20V3%2C%2064-bit%2C%202017-04-30_1928.exe?dl=0

64-bit: https://www.dropbox.com/s/yur9idcy8xe1f7c/SDR-Radio%20V3%2C%2064-bit%2C%202017-04-30_1928.exe?dl=0

�

I decided on tuning 50 to 80MHz because that band is relatively free from signals here and the Lime minus its tiny shunt coil receives that band really well.

I�m using a low pass filter with a sharp cut off about 31MHz and a band pass filter 50-80MHz and with these the local FM broadcast stations are almost eliminated from the converter output if I tune it to say 88.5MHz I see only -102dBm.

Around here 125MHz to 155MHz has lots of very strong aircraft signals so any converters using that band would need a decent filter.

�

Is your Lime RX-L input still fitted with coil MN34, 8.2nH. The Lime site has details for removing it. If it�s still in place you�ll get poor results because it represents a shunt of around 1.5 ohms at 30MHz. The two filter capacitors are 510pF so at 7MHz are about 90 ohms. The input has a 470pF in series with the connector and at 7MHz, 50 ohms this will halve the signal. Adding 100nF chips across these will help but I haven�t done this yet.

�

Allan G3PIY

�

�

�

---

From: sdr-radio-com@... [mailto:sdr-radio-com@...]
Sent: 29 April 2017 15:26
To: sdr-radio-com@...
Subject: Re: [sdr-radio-com] LimeSDR

�

�

Hi Allan,

What is your up-conversion frequency? I have used the Noolelec up-convertor which shifts the HF spectrum up to 125 Mhz. However; according to the LimeSDR input ranges, the starting range is 700 MHz. While the up-convertor does work, its not really up to the performance of a high performance HF receiver. Not only receive, but transmit is also a workaround problem for HF.

I think the best solution is to design the input and out put filters for HF and VHF use, regardless if direct or transvertor use. Need SPICE models primarily for the transformers, to design the i/o filters. While direct connection may work, a transvertor scheme may work better. The blip in the middle is eliminated. The spectrum is shifted to avoid the zero image of a direct conversion scheme. The LimeSDR phase correction does not really work well, especially for weak signal communication. On VHF I see the blip in the middle which is indicative of IQ phase and amplitude anomalies.

�

�

On 4/29/2017 5:52 AM, 'Allan Isaacs' allan@... [sdr-radio-com] wrote:

�

Hi Numeric

There�s lots of information and grumbles from buyers re the Lime SDR on the Net and I�ve added a discourse to my website.

It seems the designers and advertisers mustn�t have been in sync during the period from inception to manufacture.

I assume it�s that, otherwise it would seem to be a confidence trick to release a piece of HF kit that is 80dB down on expected performance.

After its release the Lime people suggested some modifications and indeed carried these out before supplying later examples.

Performance at HF is way down on what is generally acceptable but the thing is certainly tunable from below 100KHz.

I�ve been testing the thing and I�ve decided that the obvious way forward, other than selling it, is to add an upconverter.

My idea was to make such a device which could be easily reproduced by anyone armed with a soldering iron and a few pounds (or dollars etc). Yesterday I finished the construction of a simple prototype which allows one to hear signals down to a microvolt or two from a few KHz to 30MHz.

There are advantages of using the Lime, or any other SDR, this way because spurious responses can be minimised.

I haven�t tried it on transmit, but again a converter may be the best solution for users in the HF bands.

Essentially the Lime is OK if you�re a radio ham and prepared to experiment, but not if you�re a black box user.

http://www.radiomuseum.co.uk/SDR.html

�

�

�

�

�

Here's my lime at 25Mhz wide on HF... Some great signals

Paul Jones - NN4F
Ridgeville, SC EM93TB

Email: paul@...

Facebook.com/groups/sdrplay

On Fri, Apr 28, 2017 at 11:44 PM, Paul Jones <paul@...> wrote:

Well the lime is working quite well on HF here, not perfect, but it works, did you get a secon batch that was modified ot did you modify your own?

There are some broadcast FM images on HF, still, but it does work, I wouldn't call it a POS at all,m VHF RX works great also...

Paul - NN4F

Paul Jones - NN4F
Ridgeville, SC EM93TB

Email: paul@...

Facebook.com/groups/sdrplay

On Fri, Apr 28, 2017 at 11:38 PM, numeric numeric@... [sdr-radio-com] <sdr-radio-com@...> wrote:

 

Hello,

I started playing around with the LimeSDR. So, far not really
impressive. I Tried using the Noolelec up convertor but has poor
performance compared with the QSR1 16 bit A/D direct sampling SDR
receiver. The specifications state a frequency range of 100 kHz – 3.8
GHz for the LimeSDR with an application for ham radio use. However; the
RF input range is broken into three bands:

1. Low 700 MHz - 900 MHz. That is 700 MHz not 70MHz!!!

2. Wide: 700 MHz - 2.6 GHz

3. High: 2 GHz - 2.6 GHz

What the hell happened to 100KHz to 700 MHZ?

The transmit mode does not even match the receive bands.

Transmit provides two bands:

1. 30 MHz - 1.9 GHz

2. 2 GHz - 2.6 GHz

Obviously the LimeSDR does not serve the HF and the VHF ham bands. OK
for the 900 MHz ham and micro wave ham bands. I was hoping to use the
LimeSDR as a wide band VNA (Vector Network Analyzer); but the filters
screw up my plans.

At least the LimeSDR builders could provide SPICE models for the
transformers and the LMS7002M RF input and output ports. I suspect that
the LimeSDR could easily provide broadband continuous coverage if the
current RF stage were replaced. Hoping for a positive outcome, but at
currently the LimeSDR is a POS!

Also, the LimeSDR gets HOT!! May be about 110 degrees F.

Rant:

Why the 700 MHZ coverage, unless the evil telcos out there want to steel
the 700 TV broadcast band for their own profit. Best part of steeling
public spectrum is that you can get cell phone users to pay to access
their own spectrum. I know about the FCC auctions; should have been
halted from the very start. Recently many TV broadcasters have elected
to give up their spectrum, they are going off air. The FCC fcc.gov has
identified the broadcasters going off-air.