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Quisk Version 4.2.24 November 2023
You can now specify the WSJT-X option "--rig-name" on the Configure WSJT-X window. It used to be fixed at "quisk". Please test.
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I worked around a bug in wxPython that caused some screens to be too small. I polished the code for the RQST and ACK bits in the Hermes-Lite2 protocol. Jim N2ADR |
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Re: HiQSDR Noise floor/sensitivity
Hello Peter,
My HiQSDR shows a noise floor in 3 KHz of -111 dB at 10 MHz. So it looks like you have extra noise. But see??for a discussion of ADC noise figures. They are high, almost 30 dB. I have a preamp that I switch in for bands 20 meters and up. I have often wondered if direct sampling SDRs would be a good match for UHF transverters. BTW, I use a switching regulator to go from 13 volts to 6, and then use linear regulators to power my HiQSDR. I also suspect the power supply. Jim N2ADR |
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Re: HiQSDR Noise floor/sensitivity
Hello Guenter, Many thanks for your elaborate answer. It is clear that the signal indication seems fine, close to what you observed on the DL1CC and your home made board (well done BTW!). The noise floor on the other hand is much lower than what I observed. So it seems that there is indeed something wrong with my board. I do use the low noise regulators, etc, etc. so either the parallel decoupling capacitors are broken, or perhaps too much noise from the switch mode power supply?? I will try to replace the power supply first. Tnx, es 73! Peter Op 17 nov. 2023 17:21 schreef guenter wilfrid richter <dl7la@...>: oops, Peter, |
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Re: HiQSDR Noise floor/sensitivity
oops, Peter,
(the wrong finger here too fast) results (continued from prior post) for indicated noise levels (S-Meter setting 1 sec) 3k Bandwidth on both sets, -80 dBm IN showing displayed outputs of -79 dBm on DB1CC's board, -84 dBm on mine frequency / MHz ???????????? DB1CC????????? DL7LA 1??????????????????????????????????? -116???????????????? -104 4??????????????????????????????????? -111??????????????? -112 10????????????????????????????????? -110??????????????? -114 30????????????????????????????????? -104??????????????? -108 50????????????????????????????????? --98???????????????? -110 taking in account the different sensitivites -79 to -84 one can see that even our homebuilt solution performs astonishing well. It consist of a double silver-clad PCB, mainly ground areas on both sides, soldered VIAS into holes and power rails with hookup wire. No comparison to Helmut's board using four layers and low noise regulators. Maybe there is noise originating in the power chain (defunct regulator or else) or spurious oscillation somwhere. Additional ferrites might help. The noise figures due to ADC processing were discussed in an early stage but this was on the now archived platform when this group was on yahoo. There is however a primer to the topic on Analog Device's web, look for an article 'adc-input-noise.html'. From a HAM's view these figures are rather high indeed, but explainable. Connecting my HP-348 noise (ENR 15 dB) source e.g. will not noticeably increase display level;? only the hissing noise will just change slightly. I might add that my homebult solution needed quite a lot of ferrite beads glued to discrete locations on both sides of the PCB to damp out parasitic currents and other spurs. As to the 10 dB positive setting: the attenuator will stay at 0 dB, this feature, when activated, pulls pin 5 on connector X1 of Helmut's board to H, allowing an external LNA to be switched into the signal path before the input. Good luck... Guenter DL7LA |
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Re: HiQSDR Noise floor/sensitivity
Hi, Peter,
yes, you may be encountering an issue with your board. I have two boards, one HiQSDR from Helmut/DB1CC and my own homebuilt (guess one of the two first in Germany; Detlef/DL7IY(now SK) and I started experimenting when Jim first publihed the article in QEX in about 2010? or so). Results hereDB1CC-Board??????????? |
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HiQSDR Noise floor/sensitivity
Hi All,
I wonder if anyone can tell me what their HiQSDR noise floor is, when the input is not connected (or connected to a dummy load)? I have the impression that the noise floor of my HiQSDR board is rather high, hence I ran a few tests. I tuned Quisk to 10.7 MHz and provided a signal of -80 dBm, which showed as -77 dBm on the S-meter in a bandwidth of 3 kHz. Hence, the signal strength of the S-meter correlates well with the applied signal. The signal strength of the noise in a 3 kHz bandwidth showed a value of -101 dB(m). Ignoring the 3 dB difference, a noise floor of -101 dBm in 3 kHz equals a noise figure of approximately 38 dB! Given the hardware build up I would expect a noise figure somewhere between 20 and 30 dB, but I have not been able to find any specifications of the HiQSDR hardware which shows such specifications. So before I start debugging the HiQSDR board for anything faulty components, I wonder if anyone can provide reference noise levels (or noise figures)? BTW, I checked also on 4 MHz, and the noise floor drops 1.5 dB in 3 kHz bandwidth (i.e.: 102.5 dBm). I set the attenuator in Quisk to 0 dB, the positive Gain setting never worked.? ?? 73s, Peter, PA3BIY |
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Re: Audio Resampling clicks
Thanks Jan
It doesn't show up here as under/overruns in the status page - but I'm pretty sure that the resampling is needed to match the microphone incoming stream to the outbound IQ stream as that channel is usually the cheapest interface. Sometimes switching microphone interface devices changes the clicking behavior here - presumably because the two cards have slightly different data rates I find the clicks far more noticeable in NBFM mode and I too got reports of clicking from local repeater users. At first I ignored them and tried to deal with them by keeping the microphone input high as I thought it was PL tone leakage, but later when I investigated more closely I could clearly see and hear them in the transmitted signal. I think people don't notice them as much in SSB due to normal atmospheric noises. They are often bad on FT8, but I think that depends on vagaries of Pulse Audio (which I see has been completely removed by the Raspbian developers in Bookworm!), Again, however digital users have no way to report them back to me even if they could tell they came from my signal and not those of the rest of the pack. When they're present they're quite audible and measurable in a local receiver. On CW, the sine wave is generated locally and is usually clean and in sync - however sometimes if another mode has been in use the clicks appear for a little while during the first key down until things get settled. I guess ideally, the incoming streams would be adjusted rather than the outbound IQ since there's certainly an LPF early in input streams. I can see why it's not been done that way, however as there are a lot of inputs of different sorts that would need to be adjusted and kept track of. It might be very messy.... I still haven't got back to work on using my codec clock synthesizer to resync the output stream as I'm in the midst of chaos from new computers and a roof replacement going on all around me, but I'll try to get back to it next week. It won't really fix quisk, but might provide a useful data point for comparison and it would solve my immediate problem. M |
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Re: Audio Resampling clicks
First of all, many thanks to Jim and Ben for this amazing remote feature in Quisk.
I show my remote configuration on the attached drawing. my remote Red Pitaya SDR often runs via VHF 2M transverter on a local FM repeater and here I sometimes get reports of some clicks or short outages of the carrier wave of less than 1 second.
I count it as short breaks due to unavailability of data packages on the Internet. On the remote Quisk Config image I can see some errors on the Microphone Input. I interpret this as some Microphone Input Underrun, but maybe that's not the case? Jan |
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Re: Audio Resampling clicks
Thanks Ben, for the reply!
I've pretty well eliminated my device as the cause and focussed on the resampling method, but I will spend a little more time figuring out how Quisk processes buffers. By measurements, experimentation with modifications to the source code and a little reasoning, it appears that periodic random jumps of up to 1/2 sample value (which the present method creates) are not a good thing. ?Doing this correction to wideband IQ samples just before they are sent to the hardware the way it does, precludes doing any low pass filtering - which would mitigate the spurious transients. Unfortunately, the nasty side effects are not easy to detect with instruments because they are transient and randomized. I'm pretty sure the best thing to do would be to minimize the resampling during actual transmitting. Right now the algorithm runs continually. It probably could be disabled during normal transmissions if the underlying clock error is not too great. This would usually hide the correction because hams usually do low duty cycle transmissions. A bigger "dead band" in the feedback loop might also help by having it run less often. I've been too busy to try it, but I'm going to disable the correction code completely (not the measurement part - just the few lines that interpolate or drop the samples) and try running my high resolution variable codec clock to do the correction instead. I'm fairly certain this will do the resynchronizing without side effects, but it takes a little thought to design the PLL-like software loop that will do the adjustment smoothly. Unfortunately, this would only help hardware like mine and not other use cases. If this works, I'll report back and request an easier way to allow user supplied correction methods to be used by disabling the interpolation/drop via a configuration switch so that it doesn't require recompilation. It would also be nice to have a clean way to access the buffer fill statistics for such methods to use. I'm envisioning something easy to add to the heartbeat method in the hardware object.? My apologies to forcing everyone to follow my missteps and thinking out loud in public about this. I was kind of hoping it would bring more suggestions like yours out of the woodwork. The two clock problem is pervasive in communications and is never easy to fix! M |
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Re: Audio Resampling clicks
¿ªÔÆÌåÓýHi Mario, It reminds me of trouble I had in 2020 with Quisk on a Windows laptop, connected to a Softrock (Tayloe) radio via a Behrenger UCA202 ... it may not be the same problem, but I noticed that I/Q data out would sometimes go into what I called "buzz mode" ... it seemed that one of the ping-pong buffers in the driver got disabled, because the output would periodically (regularly every few milliseconds) alternate between normal I/Q data and silence ... made for a nasty radio signal (CW), which I would not have noticed if I hadn't been using an oscilloscope and spectrum analyzer to monitor my output. I did a lot of poking around and experimenting in the sound_wasapi.c file to track it down ... long story short, the problem seemed to be in the driver or hardware, i.e. downstream from Quisk.? Take a look at the function quisk_reset_audio_device() in that file, which resets the driver, and see where it gets called, i.e. how the problem is detected while running.? I don't recall ever figuring out what might have triggered the problem in the driver. Of course, this might not be your problem (different driver on
different OS), but perhaps re-setting your driver might help to
break out of the bad mode. Good luck!! -- Ben, AC2YD -- On 11/4/23 08:47, Mario Vano AE0GL
wrote:
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Re: Feature Request: Add option for Disable PA on each Xvtr Band
¿ªÔÆÌåÓýThat is a reasonable no coding solution.? The main limitation is a program like WSJT-X cannot change bands from, say, HF to 6M or other VHF bands without first stopping the radio and WSJT-X, and restarting each.? I know you have a settings to start WSJT-X on RX0, have not tried it as I often run multiple instances for multiple radios.? ? I am used to my K3 with the 6M and HF antennas and the xvtr interface for the VHF Xvtrs, I just hit the band button or memory and instant change for all bands 160M through 1296.? ?Running a program like WSJT-X can jump between any band like 6M, HF and VHF seamlessly.? In the case of the 5-band Xvtr it switches bands fast and silently with no relays for when I manually scan for contacts during VHF contests. ? The HL2+IOBoard is capable of the same seamless coverage with the RF1 and Aux RF connected to the Xvtr(s) and HF on the ANT jack.? I have the DB9 wired so that I can just swing the Xvtr control cable and the IF coax lines between the K3 and HL2s, one can replace the other now. ? I am a complicated user scenario ?. ?
? From: [email protected] <[email protected]> On Behalf Of
jimahlstrom
Sent: Saturday, November 4, 2023 6:36 AM To: [email protected] Subject: Re: [n2adr-sdr] Feature Request: Add option for Disable PA on each Xvtr Band ? Hello Mike, |
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Re: Feature Request: Add option for Disable PA on each Xvtr Band
Hello Mike,
I can program this feature, but I think is is not optimal. The correct approach with Quisk is to create two radios, one for HF and one for transverters. Then select the correct radio when Quisk starts. The HF radio shows only HF bands and the power amp is enabled. The transverter radio shows only VHF and UHF bands, and the power amp is off. If you have transverters that need the power amp, there is a third radio. One problem with controlling the power amp from the band screen is that you probably need to control the RF input on the IO board too. This clutters up the band screen. Is there something wrong with using separate radios? Jim N2ADR |
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Audio Resampling clicks
Hi!
I'm trying to chase down some annoying clicks/buzzes in the IQ stream sent in the audio stream sent to my Tayloe style 48khz QSE transmit mixer. I'm quite certain there is no overrun situation or anything like that occurring. Is anyone else seeing problems like this? I notice that the clicks start appearing as soon as the audio resampling fixup routine starts correcting the buffer fill level in "sound.c" around line 524. Until the first time this code runs, the audio is perfect, but once corrections start being made then very serious artifacts start appearing in the audio. ?I'm working on a Pi400 and some Pi4b units under the new "Bookworm" OS, but the problem is identical in the earlier os version. Thanks in advance for any help or advice I can get on this. M |
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Re: Congratulations to Jim!
Very pleased, long overdue.
toggle quoted message
Show quoted text
Started when I needed a Linux application for Softrock SDR and Jim obliged massively. The N2ADR QEX article which provided the basis for the HiQSDR and now HermesLite2 contributions. 73 ... Sid. On 01/11/2023 13:26, Ben Cahill wrote:
Hi all, --
Sid Boyce ... Hamradio License G3VBV, Keen licensed Private Pilot Retired IBM/Amdahl Mainframes and Sun/Fujitsu Servers Tech Support Specialist Microsoft Windows Free Zone - Linux used for all Computing Tasks |
Sid Boyce
Pierre - FK8IH
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