The idea was good!

My main antenna is the Ciro Mazzoni Baby Loop and it works perfectly but it’s a very narrow band antenna. I’m also restricted on what antennas I am allowed to put up by my landlord so if I want to get wider band reception on HF via a wire antenna it needs to he a secret hidden antenna.

So when I saw this “Loop On Ground” antenna I thought it might me the perfect option to connect to antenna port 3 (receive only) and run the second receiver on it.

The transformer box it's self comes in either SO-239 or BNC format and is a small 3D printed box costing about £75 from ML&S. In addition you have the option of buying either a 60 foot or 100 foot wire loop for £32 or £36 respectively. Of course you have the option of making your own wire loop if you want to.

Popping the back off reveals a neat and tidy PCB but to my surprise there was no weather sealing on the back of the box lid. While the lid is facing down so water will not directly enter the box given that it sits outside and on the ground in all weather I'm sure moisture/dampness entering the box will be a problem especially over winter. After I popped the back on I ran a bead of silicone sealer around the lid to improve the weather proofing and stop any water ingress from even starting. I also noted that the 3 screws holding the back on were under sized for the holes in the 3D printed box and didn't tighten up, so I replaced then with my own slightly larger self taps. None of this is major but for the £75 maybe something Omni RF want to look at in the future?

Positioning the transformer box on the ground and running the wire loop out was easy but Omni only supply 3 ground staples to hold the wire down so I added a few extra stapes to ensure no trip hazard.

The wire seems to be good quality and relatively tangle free (eventually!!!) and nicely sealed with marine heat shrink at each end. I also added a good layer of self amalgamating tape around the PL-259 and ventured back inside to do some testing.

And this is where things have not gone very well. My understanding was that the the received signal would be reduced down therefore lowering the noise floor and then you add a bit of pre-amp to bring signals back up hopefully leaving noise floor low and improving the noise to signal ratio.

On my radio I have the Ciro Mazzoni Baby Loop system set up on antenna port 1 and I've set the Omni box up on antenna port 3 which is receive only. You can probably see from the photo the noise on the Omni RF loop very high right across the band. On top of that, when I set each receiver to exactly the same frequency and conditions I'm getting clear audio (CW for most of my testing) on the baby loop but almost nothing on the Omni RF ground loop. At best if I really listen hard I can pick out a VERY faint audio output signal. Adding the pre-amp just wipes any signal out completely.

I'm going to carry out more testing over the weekend to see if I have done anything wrong in terms of setting things up but it's quite simple so not really any opportunities to get it wrong.

So, first conclusion for me this antenna doesn't seem to want to work. But that's not to say it won't work perfectly for you or anyone else. I think it's something you will need to bit the bullet and give it a try.

Of course, if anyone has any ideas or advise please shout up and I'll give it a try because I really want this to work for me.