Radio observation in hydrogen line (1420MHz)

Testing the new Nooelec 1420MHz mesh antenna 4/11/23

This new mesh antenna from Nooelec is a variation on their 17.6GHz mesh antenna – except it is a little bit bigger, stalk a bit longer, waveguide significantly bigger, and it has SMA connector rather than N-type connector, and it is about 2.5x the price!

This afternoon I compared a live plot with this antenna and my Ptarmigan band 3 military array – similar output – perhaps the signal to noise ratio on Nooelec is a bit worse.

Both used same receiver – RTL-SDR Blog V3 – and SAWBird+ H1 1420MHz filter and cascaded amplifier, and another pre-amp before the SAWBird (although I have not yet tested whether that extra pre-amp makes any significant difference).

Photo of the Nooelec 1420MHz mesh antenna below:

4 thoughts on “Testing the new Nooelec 1420MHz mesh antenna 4/11/23

  • Alex Pettit

    Hello Andrew,

    IF you want to optimize your hardware, I can help you do that.
    I know from testing that SDR# & IF_Ave saves data in linear and calibrated data values.
    These values can be converted to dB via 20* LOG10(data).

    I am unfamiliar with the units used in the ezRA software and am unable to use those values.

    SO, if you want to get your hardware configured, you need to use a setup identical to that which has been tested before.
    That being nooelec_Antenna > minimal cable to > nooelec SAWbird H1 > SDR and use SDR# & IF_Ave ..
    Once you have a ‘known’ configuration running and obtaining amplitudes in the expected range, you can experiment from there.

    If you prefer to use your current config and add data to your ezRA map, that is fine also, but I can not help with that.

    • Thanks for your offer of help, Alex. I would like to take you up on it – although first I want to finish my current hydrogen map.

  • Alex P

    I strongly suggest you Remove the Gold LNA from your setup ..
    Unless you verify its value by testing with/without, its performance is Unknown and the SAWbird has sufficient gain alone .
    If not proven otherwise, It may be the source of the large baseline drift and poor S/N.

    Set the SDR for AGC: Off Gain : Max


    • I will do this – but can’t do it for two weeks as away in London.


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.