rtl-sdr.com

Its rare for a satellite to actually be directly overhead. Most commonly they will acutally be at a lower elevation. The Lindenblad (double cross) is designed to give circular polarisation as a replacement for a linear dipole. For coverage at 90degree elevation you can use a turnstyle(crossed dipole...

I would expect this antenna to have a null directly above and below.

https://www.amsat.org/articles/w6shp/lindy.html

We can't see the actual antenna, but it's probably an L-Band circular patch antenna. The 'directional coupler on the back is actually a 90 degree hybrid used to feed the antenna and provide the circular polarisation.

Thanks for the info on that. I will definately look into openHPSDR and its derivatives.

It was an experimentation radio I was looking for. Something that works with GNU radio and has a bit more dynamic range than the HackRF for instance.

Im looking for options for an SDR based Transceivers for HF. It seems like there is a shortage of options. Hopefully the RTL community can help me compile a list and perhaps give me some feedback as to how well they work at HF? Are there other radios that can be modified to work well at HF? So far I...

I think you would need full duplex unless you have a seperate signal source.

There is no way to tell without some sort of measurement. Many antennas I get from reputable brand name suppliers dont come close to meeting their performance specs.

https://hexandflex.files.wordpress.com/2018/11/big-and-little.jpg?w=300 Hi all, Hopefully Rtlsdr wont mind me posting here with an antenna i'm selling on Tindie. In mitigation I have tried hard to provide really good documentation on how it was designed and the decisions that went into it. Hopefull...

When I connect an antenna directly(without cable) to my LimeSDRmini the antenna acts as a bit of a heatsink and helps to keep it cool. Still sits at about 50c though. When I use a cable I loose a lot of this effect.