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Elonics 4000 bandpass
by Nikos Balkanas 18 Jan '14

18 Jan '14

Hi, I would like to use my E4k dongle for wider spectrum analysis. Currently the tuner is very specific to a frequency. Is there a way to widen its bandpass filter? I have noticed some filters in src/tuner_e4k.c: Mixer filter, IF RC filter and IF channel filter. Are they of any use? Is there a librtlsdr API? TIA, Nikos

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E4K tuner blues
by Nikos Balkanas 17 Jan '14

17 Jan '14

I need to manipulate the tuners bandpass behavior. I have exported 2 more functions from librtlsdr, rtlsdr_set_filter_bw and rtlsdr_get_filter_bw and change the channel filter. However, when I use them I get libusb error(-22) **UNKNOWN ERROR**. I have tried bracketing the call with start/stop i2c repeater and disable/enable channel to no avail :-( It errs both when setting filter to 5.5 Mhz (max) and to 2.1 Mhz (min). What is going on? What other context should I provide for it to work? TIA, Nikos

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Bounce action notification
by mailman＠lists.osmocom.org 17 Jan '14

17 Jan '14

This is a Mailman mailing list bounce action notice: List: osmocom-sdr Member: benjamin(a)southpole.se Action: Subscription disabled. Reason: Excessive or fatal bounces. The triggering bounce notice is attached below. Questions? Contact the Mailman site administrator at mailman(a)lists.osmocom.org.

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Use multi-dongles to speedup scanner
by Jiao Xianjun 17 Jan '14

17 Jan '14

Hi, As a "side product" of this thread: "How to get IQ samples from multiple rtl-sdr dongles in a synchronized manner",A Matlab script is released. http://www.mathworks.com/matlabcentral/fileexchange/45024-rtl-sdr-multi-don… or https://github.com/JiaoXianjun/multi-rtl-sdr-calibration The script can use multiple dongles to do scanning, and get significant speedup compared to single dongle. (You can check reported time cost by running the script with different number of dongles) Another script uses multiple dongles to scan the same band, and combine those results together incoherently. I admit that before calibrating multiple dongles, the significant is limited. Just for FUN. README is also pasted here: Multiple rtl-sdr(rtl_tcp) dongles based Matlab frequency scanner. 1. multi_rtl_sdr_split_scanner.m Have multiple dongles run concurrently to speedup scanning wide band by scanning different sub-band with different dongle. 2. multi_rtl_sdr_diversity_scanner.m All dongles scan the same band, and then results from different dongles are combined incoherently. ------------Usage------------ 1. Assume that you have installed rtl-sdr (http://sdr.osmocom.org/trac/wiki/rtl-sdr) and have those native utilities run correctly already. For example, you have multiple dongles, please run multiple rtl_tcp in multiple shell respectively as: rtl_tcp -p 1234 -d 0 rtl_tcp -p 1235 -d 1 rtl_tcp -p 1236 -d 3 ... 2. Then run script multi_rtl_sdr_split_scanner.m or multi_rtl_sdr_diversity_scanner.m in MATLAB. ATTENTION! In some computer, each time before you run script, maybe you need to terminate multiple rtl_tcp and re-launch them again. Change following parameters in the script as you need: num_dongle = 2; start_freq = 935e6; end_freq = 960e6; freq_step = 0.05e6; observe_time = 0.1; gain = 0; sample_rate = 2.048e6; ... ------------Algorithm------------ Use high sampling rate for each frequency point. Then Auto generated narrow FIR is used to suppress noise and extract signal. At last, power of signal at each frequency is estimated and spectrum of all frequencies is generated. BR Jiao Xianjun

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RE: [hpsdr] rtl_hpsdr an RTL to HPSDR software translation server
by Richard Koch 16 Jan '14

16 Jan '14

Hi Vasiliy, It identifies itself as a Hermes FW version 2.4 I was hoping it may be useful for skimmer use. I don't know a lot about it though. -Rick =================== Hi Rich This is great! What Board ID and fw version does rtl_hpsdr send to the discovery request? your solution can be used potentially with the skimmer server and HermesIntf.dll for multichannel decoding. (I don't have a dongle yet to give this a try) 73 Vasiliy

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rtl_hpsdr an RTL to HPSDR software translation server
by Richard Koch 16 Jan '14

16 Jan '14

I am releasing to the public via GPL an RTL to HPSDR software translation server. Hosted on https://github.com/n1gp/rtl_hpsdr Screenshots listed and end. README: It currently builds and runs on Linux. It identifies and uses up to seven (theoretically eight) USB RTL2832U-based DVB-T dongles. The dongles can be set up with an up converter or use RTL direct-mode for HF receive. Or direct input to provide it's native > HF receive range. The program can be passed in a variety of command line options. One of which is a frequency offset not only for up converter use but also to allow a full range of frequency options to HPSDR programs that are coded to only allow the real HPSDR radio's (i.e. Hermes) frequency range which is from 10KHz to 55MHz. The main purpose of this program is to provide a mechanism that allows RTL Dongle owners the ability to use them on HPSDR specific software programs. One such program, cuSDR64 has the ability to control and display up to 7 rcvr slices simultaneously. With rtl_hpsdr, if your host has the horsepower, you can run 7 RTL Dongles to emulate the HPSDR rcvr. cuSDR64 also can be built and run on Linux. Since the real HPSDR (i.e. Hermes) rcvr can do up to eight rcvr slices, there is a concept of 'COPY' rcvrs in this server. This would allow one to use HPSDR programs that expected more rcvrs than were attached. Currently if a program request more rcvrs than are actually attached the rtl_hpsdr server will make copies of the last 'real' rcvr. This alows one to only have one RTL dongle attached and run PowerSDR mRX which may expect up to four rcvr slices. Refer to: http://openhpsdr.org/softwareinfo.php for a list of HPSDR supported applications. I have tested this only on cuSDR64, cuSDR32, and PowerSDR mRX. I was successful running 7 RTL dongles simultaneously on a Quad core ARM Cortex A9 based mini-pc, model EKB311 running a version of Picuntu, http://ubuntu.g8.net/ This was using R820T based dongles on a USB 2.0 hub. I did have to replace the USB hub power supply with one that provided 5V @ 2A. My 7 reveiver dongle setup: http://home.comcast.net/~n1gp/RTL_HPSDR/7_usb_rcvr.jpg Display of using 5 RTL dongle rcvrs with cuSDR64 http://home.comcast.net/~n1gp/RTL_HPSDR/5_rcvrs.jpg This PCIE card provides 4 RTL Dongles (DigitalNow Quad DVB-T) http://home.comcast.net/~n1gp/RTL_HPSDR/dn_quad.jpg Display of using 2 RTL dongle rcvrs with PowerSDR mRX http://home.comcast.net/~n1gp/RTL_HPSDR/powersdr.jpg

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What's the settling time after new frequency set to dongle?
by Jiao Xianjun 14 Jan '14

14 Jan '14

Hi, Is there any information or hint on the settling time after new frequency set to dongle? Or is there any method to read information from dongle to see if all things get stable? Can I immediately read samples after new frequency is set by rtlsdr_set_center_freq? If so, will the samples quality be degraded? Thanks! BR Jiao Xianjun

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RTL-SDR support package available for MATLAB and Simulink
by Ethem Sozer 14 Jan '14

14 Jan '14

Hi All, RTL-SDR support package for MATLAB and Simulink has been released: http://www.mathworks.com/hardware-support/rtl-sdr.html Using this support package, you can receive signals from your RTL-SDR dongle directly into MATLAB and Simulink. The package also contains several examples to get you started. Have fun and let me know if you have any questions or comments. Ethem Mutlu Sozer Principal Engineer Signal Processing and Communications Group MathWorks, Inc.

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rtlsdr_read_sync failure
by Nikos Balkanas 14 Jan '14

14 Jan '14

Hi, I need to get a few traffic data bytes ~ 16 B from my dongle. libusb's bulk transfer and therefore rtlsdr_read_sync, will fail with -8 if used with less than 1024 B. Can anyone think of another way to read them? (async also uses libusb's fill_bulk_transfer :-() I could possibly use rtlsdr_read_array, except that i don't know the block and address that I need to use for traffic data :-( Thanks, Nikos

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RTL2832/E4000 Crystal Frequency?
by Dennis Sheirer 12 Jan '14

12 Jan '14

Does anyone know if you can check the crystal frequency from one of the RTL2832 registers? Or, has anyone seen an early version E4000 dongle using a crystal other than 28.8 MHz? I've been measuring the sample output rates of my E4000 and found the output rates differed from the expected rates that I'm setting using the rtlsdr library method. https://groups.google.com/forum/#!topic/ultra-cheap-sdr/r_BLWQ5C4mw Denny

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