Re: [Discuss-gnuradio] Using the UHD API for Python Programming

2015-08-31 Thread mleech
time_spec_t() is a helper function in class "uhd", it is not a method in a uhd.usrp_source/sink. self.cmd_time = uhd.time_spec_t(0.1) Would be the correct idiom. On 2015-08-31 15:31, Tibisay Sanchez wrote: > my line is > > self.cmd_time = self.uhd_usrp_source_0.uhd.time_spec_t(.1) > >

Re: [Discuss-gnuradio] USRP Structure

2015-09-09 Thread mleech
Since most SDRs out there have fully reconfigurable-by-the-end-user FPGA and firmware images, I don't think the notion of "compromise" has much meaning in this context, further because access to the devices is freely available to ordinary user-level processes, they can ask the radio to do whate

Re: [Discuss-gnuradio] VOLK: fast way to log10()?

2015-09-16 Thread mleech
Sure, but if the flow-graph basically is decimated 10:1 by the time it reaches the log10, improvements in log10 are going to have very little impact. It is, I would assert, boldly and perhaps brashly, that log10 operations almost never need to be done at "line rate", since they are an artifice

Re: [Discuss-gnuradio] PLL not locked and GCD problem

2015-09-17 Thread mleech
The PLL not locked error is just because you've (or someone) has asked for a frequency tuning on the device that isn't possible, so the hardware is saying "can't do that". The GCD messsage is a warning. Given the message you should just have used an interpolation of 1 and a decimation of 2.

[Discuss-gnuradio] Wx issues with StaticText under F22

2015-09-17 Thread mleech
One of my "customers" (for multimode and simple_ra) has reported that at least on his system, the StaticText fields that are updated (at a coupla Hz, max) expand every time they're updated, eventually leading to an OOM issue with OpenGL. The Wx versions are here: python-matplotlib-wx-1.4.3-3

Re: [Discuss-gnuradio] PLL not locked and GCD problem

2015-09-18 Thread mleech
The "No E4000 tuner found" comes from rtl_test -t which is useful ONLY for E4000 tuners, and you have a R820T tuner. On 2015-09-18 08:38, Pedro Gabriel Adami wrote: > Hello, > > I'm tuning a frequency inside of the range of the device, that is, 107.9MHz > and 95.3MHz. When I blacklist the

Re: [Discuss-gnuradio] Examples of GNURadio

2015-09-18 Thread mleech
Try: uhd_fft On 2015-09-18 09:03, Chiara wrote: > Hi all, > > I've installed GNURadio 3.7.8 on Ubuntu 14.04 LTS and I've got two URSP B210. > > I think I've got some problems in transmission because when I run the uhd > example and try to capture the signal sent, I don't see anything. >

Re: [Discuss-gnuradio] 2Rx 1Tx overflow error

2015-09-22 Thread mleech
I would load it at the time the block is instantiated, in its "make" method, and load it into instance-specific data. On 2015-09-22 06:27, Chad R wrote: > Good day Marcus > > I am using the most recent version of UHD. The problem I was encountering was > due to the USB buffer not clearing

Re: [Discuss-gnuradio] GNU Radio installation script

2015-09-22 Thread mleech
The failure in libzmq1 is expected--Ubuntu changed package names mid-stream, so there's no way to tell which of two possible package-names to use, so it tries for both. The UHD failure is unexpected, so running: build-gnuradio -v Will give more details about errors as it builds. On 2015-

Re: [Discuss-gnuradio] GNU Radio installation script

2015-09-22 Thread mleech
Yes, although, that will get you a not-terribly-recent GR and UHD... On 2015-09-22 10:45, West, Nathan wrote: > On Mon, Sep 21, 2015 at 11:13 PM, Mike Gilmer wrote: > >> All, >> I recently asked the list some questions about getting GNU Radio up >> and running on a Windows machine (using c

Re: [Discuss-gnuradio] GNU Radio installation script

2015-09-22 Thread mleech
Hrrrm, I was pretty-sure that I'd made that update some time ago. I'll have to check my master copy when I get home. On 2015-09-22 11:08, Peter Mathys wrote: > As noted elsewhere the failure to find libzmq1-dev is expected (what is > needed is libzmq-dev) and does not affect the outcome o

Re: [Discuss-gnuradio] Chips from Nooelec R820T2

2015-09-22 Thread mleech
There will be an RTL2832U, made by RealTek. Its job is to digitize the output from the tuner, and down-sample, and put it on the USB bus. There's also an R820T2, which is the downconverter/tuner that converts to a real IF around (AFIR) 3.57MHz. There'll also be a voltage regulator or two, an

Re: [Discuss-gnuradio] RFNoc and data rates

2015-09-24 Thread mleech
Since you'd be decimating on the FPGA, your latency would be dominated by the rate at which you send FFTs to the host. In the scenario descibed, that would be about 0.01second, plus the inherent group delay of the filters in the radio, which if you're running at full ADC bandwidth won't be much.

Re: [Discuss-gnuradio] UDP Sink Size Limit - ERROR: send error:send_to: Message too long

2015-09-25 Thread mleech
If the sending machine sets DF in the IP header, then any interstitial machine that must fragment will drop the packet as well. Best to stick to MTU-sized payloads with UDP, since IP fragmentation is handled poorly in many cases--either due to policy, or bad implementations. On 2015-09-25 15

Re: [Discuss-gnuradio] complex type clarification

2015-10-02 Thread mleech
Yeah, theyre 32-bit float I and Q, and for CPUs whose native FP format is IEEE 754, that's what they'll be on disk On 2015-10-02 12:55, Jason Matusiak wrote: > I just wanted to make sure I have this right (because I always seem to > confuse myself); the complex data type is 64bits, 4 bytes o

Re: [Discuss-gnuradio] DBPSK and USRPs

2015-10-26 Thread mleech
How much attenuation do you have in the path between the TX and RX? What daughtercards? Two separate USRPs, or a single, looped back? If you turn the RX gain up, does the RX FFT change? Are you on the RX2 port on the RX side? On 2015-10-26 15:33, Washbourne, Logan wrote: > I looked at the

Re: [Discuss-gnuradio] DBPSK and USRPs

2015-10-26 Thread mleech
With antennae, or with a cable, and if with a cable, how much attenuation in the cable system? On 2015-10-26 15:54, Washbourne, Logan wrote: > Tx and Rx are on their own USRP1s, the daughter board is the RFX2400. They > are roughl 3ft apart from each other on a desk. The Rx side is using th

Re: [Discuss-gnuradio] DBPSK and USRPs

2015-10-26 Thread mleech
Consulting now, the book of armaments, errr, UHD manual: http://files.ettus.com/manual/page_dboards.html#dboards_rfx The RFX series has no TX RF gain control, output magnitude is entirely dependent on baseband magnitude. There's 70dB of gain range on RX, however. So, crank up the RX gain.

Re: [Discuss-gnuradio] DBPSK and USRPs

2015-10-27 Thread mleech
You're transmitting at 1MS, and receiving at 250ksps. Your receiver is only seeing part of your signal. On 2015-10-27 11:27, Washbourne, Logan wrote: > The RX side looks drowned out, almost like its all noise. > > I'm attaching the pictures, hopefully they make it trough the email filter.

Re: [Discuss-gnuradio] DBPSK and USRPs

2015-10-27 Thread mleech
What does the spectral plot look like? It should look very similar to the TX side of the house. On 2015-10-27 11:10, Washbourne, Logan wrote: > Thanks for the info guys! They are both using antennas btw. I came in this > morning and turned the RX gain up pretty high, roughly 45dB, and the

Re: [Discuss-gnuradio] DBPSK and USRPs

2015-10-27 Thread mleech
Try cranking your RX gain up/down 5dB and see how that affects your constellation. On 2015-10-27 11:55, Washbourne, Logan wrote: > Ok, that sampling rate mismatch was my fault. The RX spectrum looks better > after that fix. The unpacked to packed bits didn't seem to remove the zero > group

Re: [Discuss-gnuradio] DBPSK and USRPs

2015-10-29 Thread mleech
Your center frequency is in the 2.4GHz WiFi band. So, yeah, you could be seeing lots of interference. On 2015-10-29 11:41, Washbourne, Logan wrote: > So I decimated both sides, right in front of the constellation plots. The TX > side looks a lot better, no zero groupings. The RX side still

Re: [Discuss-gnuradio] USRP Latency.

2015-11-13 Thread mleech
You're probably just seeing the group delay of the interpolation filters on the N210, which for a given configuration, should be of a fixed and predictable duration. On 2015-11-13 11:18, Will Thompson wrote: > Hi > > I have question about the latency of transmissions in the N210 USPR. >

Re: [Discuss-gnuradio] how to downgrade UHD?

2015-12-04 Thread mleech
Rebuild Gnu Radio against the new UHD. On 2015-12-04 10:57, like wrote: > Hi,all: > > unfortunately it becomes incompatible after the uhd update: > > RuntimeError: > GR-UHD detected ABI compatibility mismatch with UHD library. > GR-UHD was build against ABI: 3.9.0-0, > but UHD library rep

Re: [Discuss-gnuradio] Airspy: multiple boards available with GNU Radio?

2015-12-18 Thread mleech
Quick look. libairpsy provides an API to open based on serial number. Near as I can tell, gr-osmosdr hasn't caught up with the newer airspy API. On 2015-12-18 14:07, Tom Rondeau wrote: > On Mon, Dec 7, 2015 at 2:23 PM, Mamoru Yamamoto > wrote: > >> Mr. Tom Rondeau, >> >> Thank you for

Re: [Discuss-gnuradio] gnuradios place in the state of the art of SDR

2016-02-23 Thread mleech
Also, the question is somewhat bifurcated. There are two aspects: (a) Which parameters in the hardware end of things have advanced, and at what rate, and what is considered "state of the art". This gets broken down into a few sub-categories: o ADC/DAC speeds o FPGA gate-counts and speed

Re: [Discuss-gnuradio] comparing SDR upconverters, thermal stability

2016-03-30 Thread mleech
All of them use reasonably good crystals or crystal XOs. Certainly a lot better than the RTLSDRs most of these were intended for. I assume that you're talking about frequency stability, rather than gain stability? On 2016-03-30 03:18, Daniel Pocock wrote: > Hi all, > > Has anybody been us

Re: [Discuss-gnuradio] comparing SDR upconverters, thermal stability

2016-03-30 Thread mleech
I know that some of them, like the HAMITUP, use a socket for the XO, which one could easily replace with a TCXO. Check with the manufacturers about the XO spec they use. On 2016-03-30 11:43, Daniel Pocock wrote: > On 30/03/16 16:49, mle...@ripnet.com wrote: > >> All of them use reasonably

Re: [Discuss-gnuradio] comparing SDR upconverters, thermal stability

2016-03-30 Thread mleech
Tsys is essentially irrelevant for HF receivers, since Tambient is much, much higher (thousands of K) than even some really-poor RF engineering scenarios. At HF, galactic background can be very high--1e4K or more. On 2016-03-30 10:30, Marcus Müller wrote: > Hi Daniel, > > haven't made exp

[Discuss-gnuradio] Idea for gr-osmosdr/rtlsdr drivers

2016-03-30 Thread mleech
How about a thingy that makes a note of the local high-precision time when the first samples arrive in the work() function, and then somehow make that available to higher layers, so that you can get a first-order approximation of the time skew between the streams?

Re: [Discuss-gnuradio] radio astronomy fast radio burst help requested

2016-04-01 Thread mleech
VLBI guys usually have a local H1 maser clock, they go through a complex synchronization ritual prior to the start of observations. H1 masers have short-term stability on the order of 1e-16. GPS synchronization would be a *starting point* for such things. On 2016-04-01 08:42, madengr wrote:

Re: [Discuss-gnuradio] radio astronomy fast radio burst help requested

2016-04-01 Thread mleech
The main thing is that these bursts are *weak* (< 1Jy typically), and *short duration*. Detecting a CW weak source with smaller antennae is feasible, because you can use long integration times. You have no such option here, unless you're talking about hundreds or thousands of dipoles, all phase

Re: [Discuss-gnuradio] radio astronomy fast radio burst

2016-04-01 Thread mleech
Yes, entirely feasible if you kind of "fudge and pray" on the practical realities. Even 10,000Jy is a tiny signal when cast in the context of a small antenna (2-3dBi). But can the technical infrastructure be built with relatively-cheap SDR-based kit, and Gnu Radio? Absolutely. On 2016-04-01

Re: [Discuss-gnuradio] Overflow error in benchmark receiver side "DDDD"

2016-04-05 Thread mleech
What if you make the file "/dev/null" -- does this still happen? On 2016-04-05 14:12, monika bansal wrote: > Hii, > > I am running benchmark code and on the receiver side after receiving some > number of packets(8000 so), it starts showing overflow errors ("") on > terminal. > Follow

Re: [Discuss-gnuradio] Apparent bug in gr-osmosdsr

2016-04-12 Thread mleech
Actually, I may have mis-spoke on this one. I had the gr-osmosdr source block set to "Manual" for DC-offset, and that, as it turned out, led to a very different DC-offset spike, leading to misleadingly-different power values. Turning them both to "Automatic" restored both app sanity, and min

Re: [Discuss-gnuradio] Building on ODroid C2 running CentOS 7 report.

2016-04-28 Thread mleech
Kyle Keen does GR+friends packaging for Arch/ALARM, and may have some insights. I've never tried to run build-gnuradio on ARM platforms, because the flags required vary from platform to platform, and not that many beginners are doing this for ARM platforms. YMMV, etc, etc. On 2016-04-28 12:19,

Re: [Discuss-gnuradio] Building on ODroid C2 running CentOS 7 report.

2016-04-28 Thread mleech
I use all of my Odroids that run GR in a "headless" mode--I find no reason to do flow-graph development on the device itself, and processing flowgraphs in radio astronomy just don't really need a graphical component to be running on the Odroid. On 2016-04-28 13:28, Marcus Müller wrote: > Do you

Re: [Discuss-gnuradio] [USRP-users] minimum PPS voltage for N200

2016-05-03 Thread mleech
The PPS input is conditioned with a: http://www.ti.com/product/SN74AUP1T57/description Looks to me like it should work just fine. On 2016-05-03 10:23, khalid.el-darymli via USRP-users wrote: > Hi, > > I'll appreciate any help on the following. According to the link below [1], > the PPS vol

Re: [Discuss-gnuradio] Getting one or more Ds after hours of running a GRC app on Ubuntu

2016-05-03 Thread mleech
It's possible that we're dealing with a memory leak somewhere. Could you watch the memory consumption of simple_ra over time? Also, could you just run something like uhd_fft with the same sample rate for long periods to see if it gets the same 'D' treatment? On 2016-05-03 04:32, John Shields w

Re: [Discuss-gnuradio] [USRP-users] minimum PPS voltage for N200

2016-05-03 Thread mleech
The only way the USRP knows that there's a GPSDO present is if the serial data from the GSPDO is validated. If it doesn't see that data, it concludes that there's no (internal) GPSDO present. There is no concept of "external GPSDO" -- only that *something* is providing 10MHz and 1PPS externally.

Re: [Discuss-gnuradio] Getting one or more Ds after hours of running a GRC app on Ubuntu

2016-05-03 Thread mleech
This has me thinking that this is a PHY-layer issue. How long are your Ethernet runs, and are you using Cat5e cabling? On 2016-05-03 12:59, John Shields wrote: > On 03/05/16 15:01, mle...@ripnet.com wrote: > > It's possible that we're dealing with a memory leak somewhere. Could you > watch

Re: [Discuss-gnuradio] Getting one or more Ds after hours of running a GRC app on Ubuntu

2016-05-03 Thread mleech
The native BER of 1000BASE-T is better than 1.0e-11 or so. Which means you'd expect a bad bit roughly every half-hour at 2msps (64Mbit/sec), the bad-bit probabilities get worse as you make the cable longer. On 2016-05-03 12:59, John Shields wrote: > On 03/05/16 15:01, mle...@ripnet.com wrote:

Re: [Discuss-gnuradio] [USRP-users] minimum PPS voltage for N200

2016-05-03 Thread mleech
What you're going to need to do is provide the *simplest* flow-graph that demonstrates the issue, rather than requiring the community to debug your entire end-to-end setup. Also a diagram of your setup showing the RF and 1PPS and 10MHz paths. On 2016-05-03 15:39, khalid.el-darymli wrote: > Tha

Re: [Discuss-gnuradio] INMARSAT wide signal question

2016-05-03 Thread mleech
I assume you're asking "Is there a big blue DECODE ALL THE INMARSAT THINGS" knob in Gnu Radio. The answer to that would be a resounding NO. If the question is, instead: (1) Is the Gnu Radio development environment suitable for *developing* signal-processing chains to decode INMARSAT (2

Re: [Discuss-gnuradio] UDP Source Error (on windows)

2016-05-19 Thread mleech
I'll comment that the Windows socket implementation isn't in compliance with the spirit of the robustness principle. But, whatevs. Easy enough to just remove that option for the UDP case. On 2016-05-19 08:59, Andy Walls wrote: >> OK, I was able to reproduce the issue, and it appears to me to a

Re: [Discuss-gnuradio] UDP Source Error (on windows)

2016-05-19 Thread mleech
Not sure how this would get leveraged by itself. But there are likely lots of kernel calls that have parameters that are ignored in certain contexts. I would be astonished if a general-purpose, long-lived, operating existed without that being the case from time to time. On 2016-05-19 11:58, An

Re: [Discuss-gnuradio] Multi-rtl - making multi-channel receiver out of multiple RTL-SDR dongles

2016-05-25 Thread mleech
There are a couple of issues with the rtlsdr driver used by gr-osmocom in this regard: (A) The charge-pump loop current is too constrained for the higher frequencies (B) The "dither" option appears to have a bias that causes a (small) frequency offset. The driver that AirSpy uses fixes bo

Re: [Discuss-gnuradio] Multi-rtl - making multi-channel receiver out of multiple RTL-SDR dongles

2016-05-25 Thread mleech
The AirSpy uses the R820T2 chip for the tuner, but a different sampling/DSP "engine". Yes, making the charge-pump and "dither" mods will help with phase-coherence. Somebody needs to "own" the rtlsdr driver, and merge in the last couple of years of field experience and branching that has gone on

Re: [Discuss-gnuradio] Multi-rtl - making multi-channel receiver out of multiple RTL-SDR dongles

2016-05-26 Thread mleech
A bias in the dither algorithm could explain that, which is why turning off dither clears up the problem. The drifting-out-of-lock problem is due to charge-pump current settings being too low in some cases. On 2016-05-26 11:47, Juha Vierinen wrote: > Would either of these issues in the rtlsdr d

Re: [Discuss-gnuradio] GNURadio Subdev spec

2016-06-16 Thread mleech
Use a subdev spec of: A:0 B:0 And specify the RX2 antenna for each channel. On 2016-06-16 08:08, olvhammar wrote: > Hi, > > I have a Ettus X310 and two UBX-160 daughterboards. I'm looking to receive on > RX2 on each card simultaneously. > How should I specify the subdev spec in my python/g

Re: [Discuss-gnuradio] File source problem

2016-06-16 Thread mleech
Among SDRs, there is no universal "model" for things like total gain, acceptable baseband magnitudes, etc. Even if there were, expected variations in analog behavior mean that you usually have to tweak things to make it work across multiple hardware. That's just an attribute of the analog world th

Re: [Discuss-gnuradio] Multi-rtl - making multi-channel receiver out of multiple RTL-SDR dongles

2016-06-28 Thread mleech
I just forked Keenerd's repo, which actually has support for turning dither on/off in the API, but of course, gr-osmosdr has no support for it. My fork is: https://github.com/patchvonbraun/rtl-sdr Also the difference in frequency resolution with dither on/off is very small--less than the erro

Re: [Discuss-gnuradio] new user

2016-07-04 Thread mleech
The "PLL lock messages" are normal during start-up for the gr-osmosdr rtl-sdr driver. SO, on your liveDVD image, you could do something like: osmocom_fft -a rtl=0 -f 101.1e6 -g 30 -s 1.0e6 --fft-rate 10 Does you radio station show up on the FFT display? On 2016-07-04 11:49, Darin Decker wro

Re: [Discuss-gnuradio] UHD FW Issue for NI USRP 2943R

2016-07-05 Thread mleech
The windows installer from that site seems to have been linked against UHD 3.9.3, which is why the mismatch. There was no reason to have separately installed UHD, since UHD is listed as a package that is bundled into the installer. I would remove the 3.9.4 UHD you have if you plan to use Gnu Radi

Re: [Discuss-gnuradio] UHD FW Issue for NI USRP 2943R

2016-07-05 Thread mleech
The installer that you used to install GNU RADIO *includes* UHD. You now have newer UHD interspersed with the version that came bundled with your GnuRadio install. On 2016-07-05 11:33, Sanat Kumar Mishra wrote: > UHD 3.9.36 is the latestv version of USRP Hardware Driver available. If I > unin

Re: [Discuss-gnuradio] random phase offset constantly changing with octoclock setup

2016-07-05 Thread mleech
WHat specific hardware line-up do you have? You have to use set_time_unknown_pps(), but also, if you want phase alignment (as opposed to mere coherence-with-an-offset), you need to use timed tuning commands across your systems. This will result in zero relative phase offset between boards, if you

Re: [Discuss-gnuradio] random phase offset constantly changing with octoclock setup

2016-07-05 Thread mleech
That is precisely what I'm saying, and precisely what timed-commands for tuning were invented. On certain hardware, after the tune is complete, a phase-reset pulse is sent by the FPGA. The only way for THAT to have the desired effect is to make sure that the phase-reset pulse happens at the same i

Re: [Discuss-gnuradio] UHD FW Issue for NI USRP 2943R

2016-07-06 Thread mleech
X3xx images include both firmware and FPGA cod.e On 2016-07-06 12:10, Sanat Kumar Mishra wrote: > We have unistalled the UHD 3.9.4 and flashed the image of UHD available with > the GNUradio which is: > > C:\Program Files\GNURadio-3.7\share\uhd\images\usrp_x310_fpga_HGS.lvbitx > > my question

Re: [Discuss-gnuradio] UHD FW Issue for NI USRP 2943R

2016-07-07 Thread mleech
You wanted to use the packaged Gnu Radio, which packages UHD 3.9.3, so, that header show the correct version coming out of the UHD version that is packaged with the GNu Radio package for windows. I asked you to remove the UHD 3.9.4 package that you'd installed separately, because it was in confli

Re: [Discuss-gnuradio] random phase offset constantly changing with octoclock setup

2016-07-07 Thread mleech
Is this an Octoclock, or Octoclock-G? If it's just an Octoclock, then it has no internal clocks, and acts as a high-quality clock/pps distributor. I notice you don't have the external clock inputs connected to anything, and there's no GPS LOCK indicator. On 2016-07-07 17:08, Pavan Yedavalli w

Re: [Discuss-gnuradio] random phase offset constantly changing with octoclock setup

2016-07-08 Thread mleech
Pavan: Do you have any way of verifying that you have 1PPS and 10MHz coming out of those ports on the Octoclock-G, as seen at the ends of the cables? [Looking for both the broken-Octoclock and broken-cables case]. On 2016-07-08 00:12, Pavan Yedavalli wrote: > It's an Octoclock-G (https://www.

Re: [Discuss-gnuradio] random phase offset constantly changing with octoclock setup

2016-07-11 Thread mleech
Any type of active GPS antennna will work. If you're using a passive antenna make sure you have a DC block in place--some antennae are DC shorts. On 2016-07-11 16:16, Pavan Yedavalli wrote: > Hi Marcus, > > Is this the only type of GPS antenna that I can use on the Octoclock-G? > https://www

Re: [Discuss-gnuradio] Performance for GNU-Radio: Intel i3-6100 or AMD FX-4300

2016-09-22 Thread mleech
Note that the FX series (at least, some of them) use a shared FPU arrangement. Having said that, I have an FX-8350 system that does fairly well with 6 receivers operating at 2.56Msps, doing correlation interferometry (computing 15 visibility functions in parallel for the 6 receivers). On 2016-0

Re: [Discuss-gnuradio] Performance for GNU-Radio: Intel i3-6100 or AMD FX-4300

2016-09-22 Thread mleech
Yeah, the entire FX series (I think) has a single FP-unit per *pair* of cores. This is in contrast to that which went before, the Phenom II X6, for example, had 6 FP units. On 2016-09-22 12:53, Anon Lister wrote: > The AMD only has 2 floating point units too, they just define "core" > differe

Re: [Discuss-gnuradio] How to recover USRP MB EEPROM

2016-11-18 Thread mleech
They load their operating code (FPGA + CYPRESS FX2) over USB dynamically. If you have a recent version of UHD, you should also have the images for these devices. What does "lsusb" show for the USRP1 and B100 when you plug them into the USB bus (with external power--these devices won't take powe

Re: [Discuss-gnuradio] Probable pulsar observing success at CCERA

2016-12-01 Thread mleech
This is 6MHz, centered at 611MHz (a notionally-TV channel that is allocated in North America and Caribbean to Radio Astronomy). I used a PFB channelizer with individual detectors, and then delay adjustment after the detectors and then simply added, low-pass filtered, then resampled to a precise m

Re: [Discuss-gnuradio] Probable pulsar observing success at CCERA

2016-12-01 Thread mleech
Yes, they are Digiwave ANT2084--available on-line through WalMart as it happens. But any similar 4-bay antenna will work. We use 6 of them in a 2 x 3 array. I was using a commercial combiner, but it was lossy and had poor phase balance (actually any hybrid-tree style combiner will have issues i

Re: [Discuss-gnuradio] Probable pulsar observing success at CCERA

2016-12-01 Thread mleech
Keep in mind also that B0329+54 is really the only one within reasonable "reach" for an amateur in the northern hemisphere--the others are much fainter, although if one simply added another "gulp" of antenna every paycheque or two... Also, you need a stable clock--I'm using an OCXO, but a TCXO wi

Re: [Discuss-gnuradio] Probable pulsar observing success at CCERA

2016-12-01 Thread mleech
Effective integration time was about 40 minutes. The beamshape is roughly 42 x 18 degrees from our array antenna. On 2016-12-01 15:54, Daniel R. Marlow wrote: > Hello, > > First, congrats to Marcus and CCERA. > > We are working at 21 cm (1420 MHz) and find that there are at least a few

Re: [Discuss-gnuradio] Dropped data when changing frequency dynamically using an Ettus B200

2016-12-20 Thread mleech
No data are dropped, but there will *always* be a disturbance in the analog domain when you're changing the synthesizer frequency. PLLs require a non-zero time to "lock", which means they converge to the correct frequency over some small time interval (a few msec, typically). Along with this, the

Re: [Discuss-gnuradio] What Is The Proper Way To Change Block Parameters While Running

2016-12-20 Thread mleech
If your flow-graph is GRC based, then any block parameters that can be changed at runtime can be tied to a variable. Once you have that, then you can use, for example, XMLRPC to set any variable in the flow-graph from the "outside world" (which includes "reflexive" setting from non-flowgraph pyth

Re: [Discuss-gnuradio] Using Function Probe To Get Value From Probe Signal Vector

2016-12-21 Thread mleech
Meh, I use function probes to capture 'stuff' that changes slowly--timescales of seconds or tens-of-seconds. I wouldn't do this for faster stuff, but doing that allows you to use "ordinary" python in a python module, with the probe value as calling parameter. On 2016-12-21 11:47, Marcus Müller

Re: [Discuss-gnuradio] Tune Requests

2017-01-04 Thread mleech
http://files.ettus.com/manual/structuhd_1_1tune__request__t.html Should help On 2017-01-04 12:37, Sean Horton wrote: > I have my flowgraph set up so that parameters such as rx and tx frequencies > can be changed while running, and it's being sent two frequencies to listen > to, freq1 and fre

Re: [Discuss-gnuradio] filesink to multiple files without dropping data

2017-01-16 Thread mleech
There are a whack of approaches to doing this. The filename parameter of the filesink block is runtime changeable. You could have an external process using controlport or xmlrpc to change this setting (from a variable) at regular intervals. The existing file will be closed, and a new one start

Re: [Discuss-gnuradio] filesink to multiple files without dropping data

2017-01-16 Thread mleech
If you want strict control over the file-size, then you'll likely need to write your own block. It should perhaps NOT come as a surprise that there aren't examples that cover every possible use case, since the field-of-endeavor is essentially-infinite, and there's only a finite number of entities

Re: [Discuss-gnuradio] USRPs having the same IP address on a network

2017-01-18 Thread mleech
We're going to need more of a description about how things are connected--do your USRPs have dedicated ethernet connections per computer, or are they connected to the same ports that your computers use to talk to the rest of your network? On 2017-01-18 14:05, Qurat-Ul-Ann Akbar wrote: > Hi Marcu

Re: [Discuss-gnuradio] USRPs having the same IP address on a network

2017-01-18 Thread mleech
OK, so, dedicated ethernet cards on each computer for the N210s? If so, those are, unless you turn each machine into a router that "plays nice" with the local network infrastructure, *private* connections--dont' think of them as network connections but a bus connection between your computer and t

Re: [Discuss-gnuradio] Measure and record the phase at the receiver

2017-03-23 Thread mleech
Phase is a relative measurement. Against what are you measuring the incoming phase? You can measure a PSK signal instantaneous phase-shift by computing the arctran2 between adjacent critically-sampled samples. But there's no way to look at a signal and say "what is its absolute phase" without ha

Re: [Discuss-gnuradio] AWGN using E310

2017-03-28 Thread mleech
The baseband signal is simply mixed with the LO in the hardware. On 2017-03-28 13:46, John B. Wood wrote: > Hello, all. When I connect a GRC "Fast Noise Source" block output to the > input of a "UHD: USRP Sink" (an Ettus E310) and connect a spectrum analyzer > to the Tx port on the E310 I can

Re: [Discuss-gnuradio] File sink: file size

2017-04-07 Thread mleech
Why not do the spectral and power analysis steps within GR, having it log summary data every few seconds, instead of raw data at high rate. I mean, that's what GR is good at. On 2017-04-07 14:53, Ellie White wrote: > Hello, > > As I've mentioned in an earlier email to this list, I'm working o

Re: [Discuss-gnuradio] Huge Bandwidth Issues

2017-04-17 Thread mleech
My guess is that you're operating over USB-2.0, which can only sustain an *aggregate* (TX and RX) of ca 8Msps, as far as I know. On 2017-04-17 12:17, Santos Campos wrote: > Hello! > > I'm trying to use a b200mini to implement a relay with 6MHz of bandwidth. > Would it be feasible to do this a

Re: [Discuss-gnuradio] Phase shift using a multiply block

2017-04-18 Thread mleech
Just use: complex(math.cos(angle-in-radians),math.sin(angle-in-radians)) As the constant in a multiply-const block On 2017-04-18 10:23, Trejo Treviño wrote: > I am trying add a phase-shift to my signal via the use of a multiply block, > but I have not been able to find the correct inputs fo

Re: [Discuss-gnuradio] UHD recv demuxer errors with a simple Python flowgraph

2017-06-05 Thread mleech
You might also try specifying num_recv_frames=128 or 256 in the device args, to see if that helps the USB subsystem On 2017-06-05 15:15, Marcus Müller wrote: > Hi Pierre, > > that looks more like a USB communication breakdown than an issue with > your software. > > just as a quick test: if you

Re: [Discuss-gnuradio] Signal distorted when using concurrently two USRP B210 devices

2017-06-13 Thread mleech
Thanks, George. Two things: Could you try updating to the most recent UHD version? It would be helpful if you provided your .dat files in the form of plots or graphs, highlighting the areas you consider "distortion". This will help us help you. On 2017-06-13 07:23, George Vardakis wrote:

Re: [Discuss-gnuradio] Signal distorted when using concurrently two USRP B210 devices

2017-06-13 Thread mleech
I'm having a hard time seeing a significant functional difference between the two. Could you perhaps explain? Also, maybe a diagram showing the two configurations? Do you get any error messages during a run? Are you doing reception on the two USRPs within a single flow-graph, or two separate

Re: [Discuss-gnuradio] Signal distorted when using concurrently two USRP B210 devices

2017-06-13 Thread mleech
In the two-USRPs scenario, one of the USRPs is transmitting, and one is receiving? Are they "through the air" or over a cable. If over a cable, how much attenuation has been added to the cable. On 2017-06-13 11:16, Manolis Surligas wrote: > Ok lets explain a little bit more what actually you

Re: [Discuss-gnuradio] Regarding lock protection when setting private variables in gnuradio blocks

2014-10-16 Thread mleech
Is it not the case that a given instance of a block is only ever executed by a single thread, so instance variables are completely safe to modify in-flight? There are exceptions, of course, like in FFTW, only a single thread can be "planning" at a time, due to the way FFTW does its thing

Re: [Discuss-gnuradio] Regarding lock protection when setting private variables in gnuradio blocks

2014-10-16 Thread mleech
Yeah, so, a little cerebral flatulence on my part. I think the problems come in with variables that can "change shape" during a setting operation, which could lead to horrific badness if the "shape change" happens while the work function is using the variable. Imagine a private buffer wh

Re: [Discuss-gnuradio] help accessing fft bins in python script

2014-10-16 Thread mleech
The vector sink is for debugging only. Don't use it in production code, because there's no convenient way to vacuum it out, so it grows without bound. When I've had this problem, I use a vector-probe block, and have a function probe running at a couple of Hz, and then leverage the depend

Re: [Discuss-gnuradio] help accessing fft bins in python script

2014-10-17 Thread mleech
Again, if one uses the vector-probe block, one can call the appropriate function from a function-probe, at that point, you have a variable with the contents of the FFT output vector in it, which can be used in a call to your own Python code. On 2014-10-17 12:01, Brad Hein wrote: > This sou

Re: [Discuss-gnuradio] OpenBTS-UMTS

2014-10-20 Thread mleech
Have you tried the OpenBTS mailing lists? OpenBTS is *NOT* a Gnu Radio application, although it uses the same hardware as some Gnu Radio apps, it's not a Gnu Radio app itself. On 2014-10-20 15:15, Mostafa Alizadeh wrote: > Hi all, > > Is there anyone who used OpenBTS-UMTS [2] with USR

Re: [Discuss-gnuradio] URSP noise

2014-11-11 Thread mleech
Dan: That's generally good advice, with the single exception of the BASIC/LF card family--they don't have any gain--they're just ADC/DAC buffers, so it's generally safe to loop them directly. On 2014-11-11 11:27, Dan CaJacob wrote: > Hi Lucas, > > You say you connected TXA to RXA directl

Re: [Discuss-gnuradio] USRP 1 overflow problem

2014-11-20 Thread mleech
Further, I'm not sure that benchmark_tx/rx can actually do bit rates as low as 240 bits/second, because the have a fairly-simple symbol-rate model, and the USRP1 can only support sample rates down to 192k. You said that uhd_fft also produced 'O' indications--what parameters were you using with

Re: [Discuss-gnuradio] [USRP-users] How to correct for the drift in an (FMCW) Rx signal?

2014-11-28 Thread mleech
What is the magnitude of the frequency drift? What is the magnitude of the gain drift? What are you measuring backscatter *from*? On 2014-11-28 10:14, khalid.el-darymli via USRP-users wrote: > Hi, > > Given a set of synced _(i.e., using external GPS REF/PPS)_, time-commanded > and cali

Re: [Discuss-gnuradio] two WBX boards synchronization

2014-12-08 Thread mleech
You haven't stated which USRP motherboard platform, but I assume you're talking about the USRP1, given the 4RX image. Yes, the samples will be aligned in time, but the relative phase will be random every time you re-tune or start a new session. On 2014-12-08 06:03, Nemanja Savic wrote: > Hi

Re: [Discuss-gnuradio] Bandpass Sampling

2014-12-08 Thread mleech
The N2xx series use a fixed sample rate, so there's no "deciding what sample rate to use based on Fc". There's also the analog bandwidth of the ADC to consider. If you aren't going to use a downconverter card, then the analog bandwidth of the ADC will start to roll-off at some point, so even i

Re: [Discuss-gnuradio] uhd_fft not resonding

2014-12-18 Thread mleech
See "to enable OpenGL sinks" here: http://sdrblog.wordpress.com/gnuradio-installation/ You'll use "style=nongl", instead of "style=auto" or "style=gl" On 2014-12-18 14:25, Richard Bell wrote: > Yes I'm using Unity. I forgot to mention my hardware, which is an N210 with > WBX daughterboa

Re: [Discuss-gnuradio] uhd_fft not resonding

2014-12-18 Thread mleech
milar. You'll have to research how to adjust that on Ubuntu under Unity, since I don't know myself. On 2014-12-18 15:24, Richard Bell wrote: > The key setting that mleech pointed out was setting the fft-rate lower, > uhd-fft --fft-rate 5. > > I suppose the N210 can't

Re: [Discuss-gnuradio] gnuradio-companion and multithreading

2015-01-21 Thread mleech
That would require wholesale reworking of GRC. You *really, really, really* shouldn't think of a lowly banana-pi as your *development* environment. The .py files that are generated by GRC can be generated on a "real" machine, and executed on the banana-pi, provided that you have identical GR i

Re: [Discuss-gnuradio] Move USRP LO with USRP sink block?

2015-02-10 Thread mleech
There's a uhd.tune_request() function mapped into Python land, so you can use the result of that as the "freq" parameter in a UHD sink block. On 2015-02-10 13:55, Jon West wrote: > When I transmit a signal at a certain frequency there is a large spike at > what I have set the center frequen

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