[Premium-Rx] Looking for recommendations on high performance VLF receiver.

[Alberto di Bene]

On 4/9/2018 8:06 AM, Tom wrote:

>    I am looking for recommendations for a premium receiver that will cover VLF. If it can cover say VLF to HF
> (maybe 10k/c - 30 Mc, that would be even better!)
>
>    Due to the nature and spacing of the signals, selectivity is an absolute must!  Signals can typically
> be 2 K/c apart from each other, creating all sorts of heterodyne issues.

Well, if saying "premium receiver" you mean some boat anchor of 30 (or more) years ago, the discard immediately this my 
message.
If instead you are open to the new possibilities offered by the current state of the art, then I would suggest you to 
examine these
two receivers :

Elad FDM-S2 <http://shop.elad-usa.com/sdr-radio/fdm-s2/>   A direct sampling receiver, from 9 kHz to 60 MHz in the first 
Nyquist zone, and up to the VHF region in undersampling mode.

Airspy HF+ <https://airspy.com/airspy-hf-plus/>      A novel architecture, based on a polyphase mixer recently developed 
by STM, going from 10 kHz up to 31 MHz,
                             then from 60 to 260 MHz.

Both come with accompanying software that implements brick wall filters, that make the crystal or mechanical filters of 
the past pale
in confront...

Clicking on the above links will bring you to the relevant pages of the respective manufacturers.

73  Alberto  I2PHD