SDRPlay Independent Community Forum › Forums › SDR Antennas › Antenna tuning
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May 9, 2020 at 9:34 pm #990pdhParticipant
I have an antenna tuner and am trying to use it whilst receiving only (i.e. I am not transmitting).
Learning how to use a tuner for receive only has been ‘fun’ but I have learnt that you tune it by listening for the loudest ‘noise’.
One way to finding the loudest noise (whilst tuning) is to watch the noise floor in the spectrum display – but this is somewhat hit and miss.
Is there a way to find a digital readout (in SDRuno) of the average noise floor in the 2MHz band that is being displayed? Similar to the SNR readouts.July 26, 2020 at 5:37 am #1258SolderSoldierParticipantYou might try using a signal generator attached to a wire to create a steady carrier. It might be easier to tune for a peak on a steady signal than the noise floor. I haven’t tried it so I don’t know how it will work. Just another approach.
December 27, 2020 at 1:01 pm #1578Dave RileyParticipantTuning for maximum noise or ‘S’ meter is the easy way to go but;
Usually if you connect your antenna and see some rise in the spectrum noise then you are about there..
If you want to go to FULL antenna tune for receive then look around for a small, very helpful device known as miniVNA or anything along this line..
They run for about $50 and will present you with an LCD screen illustrating a Smith chart that pins your antenna measurement to exact Resistance and Reactance values..
If this becomes interesting enough for you to try then you might even download a free program called SimSmith, very interesting..
73s from Dave-aa1aDecember 27, 2020 at 1:17 pm #1579Dave RileyParticipantTuning for maximum noise or ‘S’ meter is the easy way to go but;
Usually if you connect your antenna and see some rise in the spectrum noise then you are about there..
If you want to go to FULL antenna tune for receive then look around for a small, very helpful device known as miniVNA or anything along this line..
They run for about $50 and will present you with an LCD screen illustrating a Smith chart that indicates your antenna measurement to exact Resistance and Reactance values.. Say 50 ohms @ resonance you will see a DOT which is the Bull’s eye center of the target, like throwing darts..
If this becomes interesting enough for you to try then you might even download a free program called SimSmith, very interesting..
73s from Dave-aa1a -
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