So without much calculation i decided to build a Loop antenna with what i had laying around.
The capacitor for the loop tuning is a patch of cardboard with copper tape on it and another layer of non conductive tape above it. To tune to loop slide the capacitor piece over the antenna till desired capacity is reached.
Testing procedure:
I connected a HackRF one to the antenna and started swiping thru the spectrum in 20MHz steps. I hoped to see a noticeable bump in static around the frequency where the antenna tune would be. And i hoped that bump would move when i tinker with the slide capacitor.
My findings:
In the 50-70Mhz region there is happening something when i change the capacitor, but its very very minor and gets less with higher frequency.
The Antenna seams to have decent reception between 40Mhz and 1200Mhz, above that it is still seeing signals but i assume those are geting in over the probe itself and not the main loop.
I walked around a bit and notices the Directionality of the antenna is huge in the 100Mhz FM broadcasting band. If i spin myself with the antenna i can clearly see the null of the antenna on the SDR. ** Conclusion:**
This Antenna works some what, but there is more experimenting needed, but the directionality of the antenna was fun to observe.
Problems i am facing right now:
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Turns out my Multimeter only measures capacity down to nF and not pF
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I dont have a SWR meter
If you are on a budget (which I guess you are): Get a cheap NanoVNA or similar device. <50€ straight from China. Or get a used SWR meter / antenna analyzer from the usual places (fellow hams, internet, flea markets). It will save you so much trouble, and it is really handy to have one. If you don't, you can still do it the old-school way of receiving a known signal and simply looking at the outcome. But for that you need a known signal (or generate one). A friend with a radio, for example. Or a broadcast station. Or some local activity.
I built a mag-loop out of tinfoil and duct tape to try out an idea once, because that was faster than getting CST Studio to accept it. It works, because of course it does, but be warned that contact resistances are a bitch.
A NanoVNA is on my to buy list and will be one of he first things ima get once i have a hobby budget again