Search found 91 matches

by hotpaw2
Fri Jul 19, 2019 2:36 pm
Forum: RTL-SDR Discussion
Topic: Data buffering of rtl
Replies: 3
Views: 259

Re: Data buffering of rtl

Even a Raspberry Pi 3 running rtl_tcp doesn't buffer 5 seconds of data on a fast network. Depending on the sample rate, maybe 1 second or less, mostly from the USB transfer bursts. The SDR software maybe needs to buffer another half second, depending mostly on network and OS latency jitter. Audio ou...
by hotpaw2
Mon Jul 15, 2019 4:56 pm
Forum: Off-Topic
Topic: What (besides sw compatibility) is needed for SDR?
Replies: 2
Views: 206

Re: What (besides sw compatibility) is needed for SDR?

USB hardware devices are allowed by the USB spec to have completely different profiles. Just because the connector looks the same does not mean that the profile supported is the same. A USB flash drive is quite different from a USB audiophile DAC. Different USB profiles. And you can only communicate...
by hotpaw2
Sun Jul 14, 2019 4:12 pm
Forum: Other SDR Devices
Topic: SDR radio kits to assemble?
Replies: 2
Views: 217

SDR radio kits to assemble?

Are there any electronics kits available, requiring assembly from schematics, PCB(s) and components, for SDR experimentation? Or do all the surface-mount components required make this too difficult?
by hotpaw2
Mon Jul 01, 2019 4:26 pm
Forum: Troubleshooting Help
Topic: Spikes on HF frequency
Replies: 6
Views: 502

Re: Spikes on HF frequency

Those periodic spikes and waves look like the symptoms of electronic switching RF noise. This kind of RF noise can be generated by LED lights, power supplies, network equipment (cable modem, WiFi/ethernet hubs, etc.), PCs, monitors, printers, and etc. Not only in your place, but from inside any near...
by hotpaw2
Mon Jul 01, 2019 12:38 am
Forum: Troubleshooting Help
Topic: Has anyone managed to get a Raspberry Pi 4 working with an RTL SDR?
Replies: 8
Views: 705

Re: Has anyone managed to get a Raspberry Pi 4 working with an RTL SDR?

A bunch of us are probably still waiting for more Pi 4's to be in stock and ship.
by hotpaw2
Tue May 28, 2019 1:06 pm
Forum: RTL-SDR Discussion
Topic: Using SDR and computer to send data over internet
Replies: 3
Views: 623

Re: Using SDR and computer to send data over internet

Whether possible depends on the protocol used by the 900 MHz radios (e.g. any message response latency requirements, etc.). If possible, it would require some full duplex SDR radios, such as the Hack RF, LimeSDR, Ettus Research, and etc. which are more expensive than RTL-SDR plug-ins.
by hotpaw2
Fri May 24, 2019 6:59 am
Forum: RTL-SDR Discussion
Topic: Sigmira: Sr. Citizen Woes
Replies: 4
Views: 621

Re: Sigmira: Sr. Citizen Woes

Why not ask the sigmira developer? Probably knows a lot more than anyone here.
by hotpaw2
Tue May 21, 2019 3:15 pm
Forum: Troubleshooting Help
Topic: Signal chain w/ RTL-SDRBlog Dongle v3 + RTLSDRBlog Wideband LNA & FM Filters?
Replies: 2
Views: 432

Re: Signal chain w/ RTL-SDRBlog Dongle v3 + RTLSDRBlog Wideband LNA & FM Filters?

Actually, there is a trade-off. One solution does not fit all. A short coax run between the antenna and the LNA or SDR radio means less signal attenuation. But, unless you are on the very top of a hill and off-the-grid, one usually gets better reception and less RF interference by putting the antenn...
by hotpaw2
Mon May 20, 2019 11:46 am
Forum: RTL-SDR Discussion
Topic: Raspberry pi 3 b+ and rtl-sdr
Replies: 2
Views: 539

Re: Raspberry pi 3 b+ and rtl-sdr

Would you like to use your Pi with a monitor and keyboard attached? Or headless, as a remote RTL-SDR rtl_tcp server? For the latter, I just use the Raspbian Stretch Lite OS image, boot it up, then download and and run the rtl-sdr install scripts via ssh. There are a bunch of SDR client apps that wil...
by hotpaw2
Thu May 16, 2019 6:24 pm
Forum: RTL-SDR Discussion
Topic: LNA power supply?
Replies: 6
Views: 816

Re: LNA power supply?

Interesting. I've always assumed that unwanted interference was a subset of noise, not a disjoint set.