Hi Bodger, I'd like to know that too.
Antenna building and modelling using software and testing them and analysing them has been my main radio passion for years, because I live in the sticks I can hang them from trees, they are made from aluminium welding wire.
I've done a bit with the SDRPlay RSP2 on HF and also multi-coaxial-collinear VHF-UHF verticals using an inexpensive RF noise source and a MiniCircuits bi-directional coupler from eBay
The coupler is a MiniCircuits ZFDC-10-5-S+ which is good for 1MHz to 2GHz and the noise source is one of these
https://www.ebay.com.au/itm/Noise-Sourc ... Sw4PxaBoVR
I can't find the original article online that started me off but if you search you'll find a variety of articles that deal with sweeping filters, antennas, etc all using the same principle.
There's a post on this forum from someYguy that might get you interested.
Really great for sweeping 10MHz blocks of spectrum using an SDRPlay device
Terrific visualisation of what's happening
Versatile for a range of things, eg sweeping common mode chokes, sweeping antenna tuners to see depth of notch or bandwidth
Dynamic range measuring ability is limited by the return loss specs of the coupler, eg.
https://www.minicircuits.com/WebStore/d ... -10-5-S%2B
Absolute values are not easily obtainable because of the lack of ideal "flatness" of a cheap noise source and the coupler.
With the things I do, the relative values are what counts.
Here's a pic of the setup used to evaluate the notch obtainable by using an antenna tuner as a shunt to ground.
viewtopic.php?f=8&t=127&p=9283&hilit=an ... uner#p9283
Using an RSP device as test gear has great potential, especially given it's += a dB or two flat range to 2GHZ.
All we need is a nice tracking generator and more dedicated software
Here are a couple of screen shots of one of the 160m loops, SDR-Console software was easiest to adjust for spectrum range and colour.
Links to originals:
With the accessibility of SDRPlay hardware and the range of software and it's uses, we can confirm on the bench that the sky is the limit