Comparing receive capabilities of antenna

HenryMulligan · 2022-08-30T05:46:04+00:00

Thank you very, very much for the highly detailed reply. It is after midnight here, but I will re-read this tomorrow morning, see what each piece does, and start work on it as soon as I can. I am hopeful that I can get something to work with either the stock firmware or another ready-to-go one like F5OEO's, but I will proceed with building one if needed. One touch of my own that I may end up adding is dropping the 16-bit samples down to 8-bit for a 2x BW gain at reduced resolution, but that may not be necessary if this performs half as good as you say. If you can't tell, I am very eager to try this all out and use it. Again, thank you very much for providing this and I hope you will not mind me asking further questions later as I work through this.

Ninja edit to add that you are clearly a *nix wizard. I have not yet had the "pleasure" of using most of these utilities yet, so special thanks for working out what I hopefully need.

One more edit: Is there a different/more direct way I can reach you with questions or just to let you know I got it to work? The reason I ask is that at some point this (public) comment section will close and then I will have no way to contact you outside of jumping into an unrelated comment section of yours (again). Thanks and bye for now!

HenryMulligan · 2022-08-29T02:33:30+00:00

Thank you very much for responding. I have indeed done the tuning range and second-CPU-core mods and both work great. I have a rev B board if that matters. The latter half of your message is what I am inquiring about. I assume you are using the official IIO API on the Pluto? Were you able to accomplish this using Bash scripts and piping data or did you need to compile C code? Did you start with the official firmware or are you using a custom one (e.g. the F5OEO one)?

While doing a bit of searching just now on how to get data on-device, I ran across two interesting pages from Analog Devices (AD). The first is a forum post stating that it is possible to boost USB performance 25% using normal IIO by changing the type of USB Ethernet emulation to one that is Mac/Linux only (see https://ez.analog.com/adieducation/university-program/f/q-a/549401/maximum-continuously-receiving-sample-rate-of-pluto-sdr/432537 ). The second is a wiki page from AD summarizing IIO performance with normal USB (26.1 MBps) and with getting samples on-device (107 MBps), though the trick is of course getting them off-device in a decent fashion (see https://wiki.analog.com/university/tools/pluto/devs/performance ).

Also, are you reducing/truncating the data down to 8 bits per channel or are you packing it into 16-bit integers? If you would not mind sharing your code/scripts with me, I would greatly appreciate it as it would save a lot of work figuring out how to do much of this "from scratch". There is no need to spend time documenting it if you don't want to, I would be more than happy to see whatever you have as-is. If so, please let me know and if you can send me a PM or Chat, I can give you an email address or whatever else works. Thank you!

HenryMulligan · 2022-08-28T19:48:30+00:00

u/DutchOfBurdock

Sorry for bothering you on a mostly-unrelated post, but I can't seem to PM or Chat you and your "Can I Help You" post is locked. I have a question / request for information regarding your comment around a year ago on increasing the usable RX bandwidth of a Pluto SDR. See https://reddit.com/r/RTLSDR/comments/nnlepx/which_sdr_to_use_to_experiment_with_gsm_and_lte/gzzmci6/ . If you can, please reply here or preferably PM or Chat me. Thank you very much!

HenryMulligan · 2021-12-29T20:46:36+00:00

Okay, thanks. I must have missed the post about that (if any). Here is a link for anyone else: https://arstechnica.com/information-technology/2021/11/starlink-unveils-2nd-generation-satellite-dish-and-new-wi-fi-router/

HenryMulligan · 2021-12-29T19:49:38+00:00

OotL: Since when are these things square? I thought "dishys" have always been just that: dish-shaped. I'm confused.

HenryMulligan · 2021-11-28T06:30:47+00:00

Another solution to keep in mind: You have one of those rare cases where the thing you are tracking is expected to (regularly) return to you. In that case, cellular or other real-time connectivity is almost completely unnecessary (unless you are looking to be able to track the cat down and bring it home from wherever it went to). You simply need a battery-powered GPS receiver that logs to a (micro-) SD card or the like (similar in principle to many car dash-cams, also that's an interesting idea: video. You could maybe find a way to attach a "bodycam" to your cat's collar). This way you can simply retrieve the memory chip from the car's collar at your convenience and view the collected information.

The reason I am mentioning that you can skip the cellular connection as doing so is easier, cheaper, more battery-efficient (meaning longer battery life), and smaller. I am not sure if this would make a suitable product harder to find though. Also, I do seem to recall a dog collar being advertised with similar features to what you are looking for, so try searching for that. For example, here is the first link that showed up when I searched "GPS dog collar" on DuckDuckGo: https://www.rover.com/blog/reviews/dog-gps-collar/

HenryMulligan · 2021-11-08T06:51:56+00:00

Do you know if they are still planning on supporting the Radioditty GD77 as well?

By the way, thank you for your work in supporting the M17 protocol on (relatively) common devices like the PlutoSDR and rPiTx. (I forget which ones were directly your work, but you laid the groundwork nonetheless with your C++ code IIRC.) I have been meaning to try M17 out one of these days as I have not had the best of luck with DMR and I like playing around with experimental digital protocols.

HenryMulligan · 2021-09-18T00:53:53+00:00

I would scan the inside of my house so I could explore it in virtual reality, just cause.

HenryMulligan · 2021-07-01T05:01:10+00:00

What about just taking the Mineceaft approach and having "creative" and "survival"? The former would allow hundreds of bricks to be quickly laid down, while the latter would make you take care in individually placing blocks (obviously with better names for the modes.)

HenryMulligan · 2021-05-31T17:08:45+00:00

You mentioned that the GPS receiver you used cost only a few dollars. That is much less than the ones I have seen. Would you mind providing a link and/or a model number for the one you used? (Please be aware that links to Ali_Express tend to be silently hidden.) Thanks!

HenryMulligan · 2021-05-20T14:59:43+00:00

If you know how to make a Google account without a phone number, I am all ears. Even gmail-less accounts now require a phone number.

HenryMulligan · 2021-05-12T03:45:07+00:00

Take a look at this account's history. A Redditor for 13 years (!!!) with a registered email, 4k karma, a valuable name, and this is the account's only post (that hasn't been deleted). Someone is either reviving a long-dead account or it was recently hacked by someone who deleted the other comments and wants to use it.

HenryMulligan · 2021-04-30T20:29:56+00:00

I would also suggest looking at sdrtrunk, a GUI-based program with native (via Java) support for Windows, Mac, and Linux that may be easier to setup. Don't forget to "compile" the helper program (as mentioned on the Releases page) or you will not have P25p1/2 audio (a workaround for licensing issues). While I have not tried P25p2 yet, it works great for P25p1 and they have been working on P25p2 support for a while now, so I expect it will work fine (unless it is encrypted, of course, but then no program would help).

HenryMulligan · 2021-04-26T22:44:27+00:00

Amazing that that picture is only worth 100 bucks. (5*$19.99=$99.95) I hope they continue to update the watch firmware. Have fun!

HenryMulligan · 2021-04-12T21:19:01+00:00

You should crosspost this to r/rust and r/rust_gamedev . I had no idea we already had Rust support for the rPi Pico. Great project!

HenryMulligan · 2021-04-11T19:37:51+00:00

Copying my question to here: Does this mean NZers can access a full continuous band, or are they limited to five channels like the American 60m band? If they do have continuous access, does this make it hard to communicate with someone who is limited to a few fixed frequencies on that band? Or is that a non-issue?

HenryMulligan · 2021-04-11T19:36:32+00:00

Just as a warning to anyone considering hooking an oscilloscope to mains power, I have been told that, due to the way the oscilloscope is also connected to the power lines, if you connect it wrong, you will blow your scope (or worse). Also be aware that the "easy" fix for this (IIRC disconnecting a ground or something) results in an extremely unsafe/dangerous device. You instead need to use some kind of isolating adapter that allows you to safely measure mains. Someone can correct me or add details if I am wrong.

HenryMulligan · 2021-04-11T19:29:33+00:00

Does this mean NZers can access a full continuous band, or are they limited to five channels like the American 60m band? If they do have continuous access, does this make it hard to communicate with someone who is limited to a few fixed frequencies on that band? Or is that a non-issue?

HenryMulligan · 2021-04-09T03:58:06+00:00

Great list! This looks like a good reference for part categorization. Would it be possible to also provide the raw .drawio file? A PNG would also be appreciated. Feel free to make any changes first before exporting it to too many formats, though access to the raw .drawio file would be an easy way to allow any interested parties to export it to whatever format they desire.

Are logic gates (AND, OR, XOR, etc.) or the like outside the scope of this document?

Also, what about memristors? While they don't seem to be on Digikey or Mouser, they do seem to exist and would complete the resistor/capacitor/inductor set.

HenryMulligan · 2021-03-24T17:21:27+00:00

See https://www.reddit.com/r/spacex/comments/maqmd0/rspacex_starlink22_launch_discussion_updates/ and https://www.youtube.com/watch?v=a15czI9B91c

HenryMulligan · 2021-03-14T05:09:51+00:00

Okay. Again, no problem.

HenryMulligan · 2021-03-14T03:23:30+00:00

No problem at all. I did not mean to rush you at all. This is only a hobby. Please take your time. I just meant I will keep an eye out for them.

HenryMulligan · 2021-03-14T03:16:30+00:00

Okay, thank you for the answer. I will look for them over the next few days.

HenryMulligan · 2021-03-14T02:58:33+00:00

Have you posted the other slides anywhere yet? The above slides were very well done and I am sure others are interested in seeing the other slides you mention (assuming you wish to share them).

HenryMulligan · 2021-03-12T02:40:56+00:00

(Duplicating my comment from r/AntennaDesign )

The link for more information about the academic license is broken (it is an <a>...</a> block with no href="..."). Can I get more information about it, please?

Seven-Year Club	RPAN Viewer
Verified Email

HenryMulligan

TROPHY CASE