Архив за 20.02.2020

Comment on About RTL-SDR by Bob Klahn

Scientist means nothing without the specialty.

Troubleshooting Help • Re: No Source for RTL-SDR in GNURadio [GNURadio/RTL-SDR/Windows]

the simplest solution would be to install linux on your machine (you can install Ubuntu or whatever along windows), Gnu Radio, and everything get easy!
Good luck!

Statistics: Posted by anoyanfiles — Thu Feb 20, 2020 11:30 pm


Pixel Pro-1B Mag Loop vs. PA0RDT Mini Whip

I bought a 2nd-hand Pixel RF-PRO-1B antenna and unimpressed thus far when comparing it to a PA0RDT (Roelf Baker made) active mini whip.

The Pixel is ~5 feet off the ground, mounted to a tripod, isolated properly (per instructions), sitting on a cement patio, about 5 feet from the house. 50 feet of 75 ohm coax connects the antenna to RSP2 SDR w/HDSR software.

The PA0RDT is ~20 feet off the ground, mounted to a PVC pipe, no grounding, sitting on a wooden deck, about 5 feet from the house. 50 feet of 75 ohm coax connects the antenna to RSP2 SDR w/HDSR software.

While tuning through the HF dial last night, all signals were significantly stronger with the PA0RDT. Changing the orientation of the loop made no difference.

Shannon Volmet was easily understood with the PA0RDT; with the Pixel, it barely produced a signal in the waterfall. Greece beacon "SVO" likewise was strong and very audible w/the PA0RDT; the Pixel was non-existent. STANAG signals were very pronounced and strong w/the PA0RDT while the Pixel was pulling in the signal, it was much weaker and very evident in the waterfall display.

Why would the PA0RDT mini whip outperform the Pixel mag loop? The PA0RDT should be grounded to improve signal and lower noise. Mine is not grounded; it is not performing as efficiently as it could yet it runs circles around the Pixel mag loop.

Does height above ground affect the Pixel?

Am I incorrect to assume that the Pixel mag loop should outperform the PA0RDT?

submitted by /u/ultravista_2
[link] [comments]

KerberosSDR • KerberosSDR sync issues

I have the FIR tap size set to 0, decimation set to 1, and antennas disconnected, but I am unable to get my KerberosSDR to sync correctly. In the image linked below, I have performed both sync steps (Calibrate IQ was pressed ~575 on the x axis in the bottom two graphs. In the ABS x Corr plot, I am not getting the three converging peaks. In the Phase Diff history, the red and green lines are converging but the yellow one is not. Does anyone know what could be causing this? I have tried restarting the software/my computer and switching cables and usb ports, but nothing has solved it. I am running the KerberosSDR directly from a laptop instead of using a Raspberry Pi or Tinkerboard

This issue did not occur until the first time I used the web interface for the first time, so I am wondering if it could be related to that.

Image: https://drive.google.com/file/d/17eH8SW ... sp=sharing

Statistics: Posted by mrice98 — Thu Feb 20, 2020 10:27 pm


KerberosSDR • KerberosSDR sync issues

I have the FIR tap size set to 0, decimation set to 1, and antennas disconnected, but I am unable to get my KerberosSDR to sync correctly. In the image linked below, I have performed both sync steps (Calibrate IQ was pressed ~575 on the x axis in the bottom two graphs. In the ABS x Corr plot, I am not getting the three converging peaks. In the Phase Diff history, the red and green lines are converging but the yellow one is not. Does anyone know what could be causing this? I have tried restarting the software/my computer and switching cables and usb ports, but nothing has solved it. I am running the KerberosSDR directly from a laptop instead of using a Raspberry Pi or Tinkerboard

This issue did not occur until the first time I used the web interface for the first time, so I am wondering if it could be related to that.

Image: https://drive.google.com/file/d/17eH8SW ... sp=sharing

Statistics: Posted by mrice98 — Thu Feb 20, 2020 10:27 pm


I just discovered WEFAX! Fun to receive a fax again. Got a fairly strong signal from the Pt. Reyes station this morning.

I just discovered WEFAX! Fun to receive a fax again. Got a fairly strong signal from the Pt. Reyes station this morning. submitted by /u/Nar1117
[link] [comments]

What should I do with all the old, crappy dongles?

I've finally replaced all the cheap old dongles with better receivers.

What should I do with all the old dongles, you know, those with plastic cases, cheap crystal oscillators and the MCX or Belling-Lee connectors?

Logically I've considered thinking of what applications don't require much frequency accuracy, or noting which dongles had decent receive sensitivity in what frequency ranges and try using them for something specific. For those with a Belling-Lee (PAL?) connector, I've thought about desoldering the coaxial connector and either replacing it with a more useful SMA connector or soldering it directly to a specific antenna or coax within an enclosure for a specific purpose.

So far the only conclusion I've reached is pretty general, to build them into projects for which their performance is acceptable, and where I may not want to risk damage to the nicer devices. The difference in cost is typically small, between an old generic $7 device and the formidable $22 RTL-SDR.com v3. One goal here is utilization, so the old devices don't simply collect dust until complete obsolescence.

Should I just sell them for cheap at the hamfest? Does anyone have any better ideas?

submitted by /u/PipingHotSnare
[link] [comments]

Troubleshooting Help • Re: Dongle unusable using long wire antenna and 9:1 ballun.

Hey thanks for the help!!! Reading the replies, I suspect both responses may be correct.

1) I built a crystal radio way back. It would only pick up one station at first on all frequencies. I ended up with 3 wave traps and 2 antenna tuners before I could pick up anything else - but then it would pick up Chicago at night! The thing looks like something out of a 50s ScI Fi movie now with all the knobs :) but it works very well here at the same location.

2) I forgot to mention that the receiver is inside a metal RV and the antenna is hanging off the top of the RV on one side - so maybe that huge chunk of metal is interfering? I'm on 5 acres - the closest power line is further than it would be in a normal neighborhood and the closest radio station is at least several miles away - so hopefully that is the problem.

There are so many filters and what-not that I wasn't sure what to try next, but I will move the antenna and get an AM filter...and I will update the post when I have further results in case it helps someone else.

Thanks again!!!!! - Jon

Statistics: Posted by idioma — Thu Feb 20, 2020 6:32 pm


Comment on A Good Quickstart Guide for RTL-SDR Linux Users by Dark Speed

you must be doing it wrong. I have been using *nix since the late 90’s. Very anti M$

Troubleshooting Help • Re: Dongle unusable using long wire antenna and 9:1 ballun.

Looks like intermodulation from multiple very strong stations nearby. You can try an AM bandstop filter. But your location (due to building wiring, power lines, other nearby electrical equipment, etc.) might be generating too much EMI/RF noise for any HF antenna there to be usable.

Statistics: Posted by hotpaw2 — Thu Feb 20, 2020 4:34 pm


Перевод
Рубрики
Архивы
Февраль 2020
Пн Вт Ср Чт Пт Сб Вс
« Янв   Мар »
 12
3456789
10111213141516
17181920212223
242526272829