430-440 MHz FX interferometer

[David Lonard]

Hello everyone,

I have replaced a VHF interferometer (137-147 MHz) with a updated version at 430-440 MHz in an effort to avoid persistent RFI I have been experiencing at VHF frequencies. 

The UHF upgrade appears to be working very well and can achieve higher resoultion on the ~20 hectare property that I use to host my interferometer that has a ~400 meter baseline. 

Much greater attention to LNAs and getting enough signal to my LimeSDR SDR was needed, but it looks like it is going to pay off. The attached file has some preliminary results from an observation of Cas A. I am now performing a 30 day synchronized sidereal day run to test system stability and whether weaker radio sources can be detected. 

David

[Jim Sky]

Hi David,

That is a great start on your interferometer.  Greatly envy your wide expanse of antenna property. Will your FX correlator be real time?  Is that possible?

Jim Sky

[David Lonard]

Jim,

It is already 'real-time' in that the FX step is done in the GPU and recorded to a file as it observes. No SSD storage is required since this is a wire-connected interferometer. I travel out to the location about once every two weeks to retrieve the data, but I suppose that it might be possible to automatically post the data over the internet. The integrated visibility data totals 64 mb per day.

David