Search found 100 matches

by hotpaw2
Fri Mar 09, 2018 4:10 am
Forum: User Projects
Topic: New SDR app for iOS (iPhone)
Replies: 5
Views: 8516

New SDR app for iOS (iPhone)

Hi. A first version of my iOS SDR app is nearing completion. So I'm interested finding a few users who would like to beta test a pre-release of the app, and provide some feedback. The beta test requirements are having a 64-bit iOS device (iPhone or iPad) running iOS 11.2.x or newer, having Apple's T...
by hotpaw2
Tue Mar 06, 2018 6:33 pm
Forum: RTL-SDR Discussion
Topic: R820T2 out-of-production?
Replies: 1
Views: 1750

R820T2 out-of-production?

Are R820T2 tuner chips by Rafael Micro no longer in production? If so, when they run out, how long will it take vendors to redesign RTL-SDR PCBs and librtlsdr code for a newer or replacement front-end tuner chip?
by hotpaw2
Tue Mar 06, 2018 6:28 pm
Forum: RTL-SDR Discussion
Topic: MTBF - Mean Time Between Failure
Replies: 2
Views: 1770

Re: MTBF - Mean Time Between Failure

A good MTBF calculation would require a very large statistically significant sample set.

My tiny insignificantly small sample set was, out of 4 RTL sticks, one died that was only a couple months old. Some of the others are over a year old.
by hotpaw2
Sun Feb 25, 2018 7:29 pm
Forum: Other SDR Devices
Topic: SDR to locate cochlear implants
Replies: 4
Views: 4041

Re: SDR to locate cochlear implants

You can't sniff for iBeacons with arbitrary identifiers with an iOS device, but there are reportedly apps for Android mobile phones (perhaps you can borrow one) that will allow one to search for any advertising iBeacon using any identifier. The 2.4 GHz ISM band that BLE uses is too high for generic ...
by hotpaw2
Sat Feb 24, 2018 6:04 pm
Forum: RTL-SDR Discussion
Topic: Do you need a high performance pc to play SDR?
Replies: 3
Views: 2539

Re: Do you need a high performance pc to play SDR?

I use a tiny Raspberry Pi 3 for demodulating analog AM and FM from a RTL-SDR. No problem. No fan noise. The heat sink on the Pi only gets slightly warm. I also can carry my iPad, Pi, and antenna far away from the RF noise of big PCs and household electronics. A Pi Zero W might also work if you want ...
by hotpaw2
Fri Feb 23, 2018 4:17 pm
Forum: Antennas
Topic: Grounding of Active Antennas Like The Mini-Whip
Replies: 6
Views: 6895

Re: Grounding of Active Antennas Like The Mini-Whip

A mini-whip likely uses either the outer coax shield or the mast as part of the antenna (the counterpose), so it likely doesn't matter as long as both are far away from noise sources (e.g. up high).
by hotpaw2
Thu Feb 22, 2018 7:28 am
Forum: Other SDR Devices
Topic: Airspy HF+ on a Raspberry Pi?
Replies: 4
Views: 5473

Re: Airspy HF+ on a Raspberry Pi?

I just posted source code on github of a very simple rtl_tcp server for the AirSpy HF+: hfp_tcp_server.c https://gist.github.com/hotpaw2/8c720c324ac0794aa7bf98c505eb61d5 This allows me to develop SDR clients for both the RTL-SDR and the HF+ using the same rtl_tcp protocol for both (except for the di...
by hotpaw2
Thu Feb 15, 2018 9:55 pm
Forum: RTL-SDR Discussion
Topic: Raw digital output from usb dongle
Replies: 8
Views: 5788

Re: Raw digital output from usb dongle

How does one determine how much PLL settling time is needed after each frequency jump? I assume the IQ data is mostly garbage until after the PLL + internal filter settling time.
by hotpaw2
Wed Jan 31, 2018 6:10 pm
Forum: Troubleshooting Help
Topic: NooElec NESDR SMArt - Error: Cannot access RTL device
Replies: 4
Views: 4228

Re: NooElec NESDR SMArt - Error: Cannot access RTL device

I also helps to have more than one RTL device available to test, to see if the problem is with software or with hardware. I had one of the smaller NooElec devices get hot and fail.
by hotpaw2
Mon Jan 29, 2018 9:04 pm
Forum: RTL-SDR Discussion
Topic: Looking for SDR software with plugins
Replies: 3
Views: 1942

Re: Looking for SDR software with plugins

On my Raspberry Pi, running a Linux variant, I use rtl_tcp to connect to the RTL-SDR, and plug my own DSP software (filters, demodulators, spectrum visualization, etc.) directly into the tcp-ip socket IQ data stream from rtl_tcp, which is an extremely simple interface to the raw IQ data.