Loop Antenna Idea

[uksoundz]

Hi,

My friend has a handheld shortwave receiver with a longwire he runs round his room as the antenna, and can receive so much more than me on my FT450 and SRC vertical, I'm thinking about doing something a little similar but want some advice on whether it would work and any tweaks I could do etc.

Anyway I only have a modest garden, already decorated the house with enough antennas so don't want to be putting up any fishing poles etc.
I want to run a loop around the garden, well more of a square with one side a little longer than the other, it would only be around 6 - 8 ft high for the most part and maybe 12 - 15ft high the rest, I understand the higher the better, but I would have to make do with this. I can figure I can fit around 98ft of wire out, maybe a little more, I want to terminate it at a 9:1 unun outside, and coax to the ATU, only because I have one lying around and don't want RF in the house, because my antenna tuner is quite a distance from the window, it order for me to move the ATU nearer would require a lot of work lol.

Anyway I'm rambling, would this work, could it tune up ? Any ideas ?

Thanks guys.....

[Andy]

You need an antenna expert, but I've turned up instead!

Assuming your loop acts as a full-wave into the balun, it would be resonant on 98ft/3 = 32 metres, or around 10 MHz. It would (like all antennas) also work as a general-purpose SWL antenna for listening around, but of course it would have peaks and troughs in its response.
I'd like to know why your friend can hear more on his h/h than you can on your 450 though. I'm not sure what an SRC vertical is, perhaps that is the limiting factor here.
I had a friend once who owned a rather 'bottom end' receiver and he always used to crow about how 'sensitive' his RX was compared to my Trio/Kenwood R1000. Of course I knew that most of the stuff he was hearing was cross-mod, images and breakthrough from unwanted freqs, but there was no telling him....

[mangina]

First off your mates antenna is at another qth and a different antenna so results will be different.. The vert you have is the vert with a 9.1 unun or whatever ratio it is at the base i presume.. If you have not got a decent earthing system for this type of antenna your losing out on rx and tx sigs straight away..

why not run the loop all the way round your garden as a closed loop , first advantage is its a balanced antenna so shouldn't give you any stick rfi wise. feed it with ladderline all the way back to just outside the shack window , 1.1 current balun or choke balun and a short run of coax to the atu/rig rig..

alternativly to avoid using feedline run the wire round your garden and terminate both ends at the shack window , 1.1 current balun /choke balun , coax to atu/rig if the atu can't find a match use a 4.1 balun. try using a 1.1 first though.

if your going to run a long wire/random wire / end fed type thing , like the vert you need a decent ground to get the best from them.

[uksoundz]

Just done it, had to use a 4:1 balun though, I got as much speaker wire out as I could, around 38 - 40m, it doesn't require a tuner on around 8.1mhz and 15.600mhz Wish it were a little longer now, the vertical seems to pick up further away stations stronger, and the loop seems better on local, oh and a lot less noise on the loop.

[uksoundz]

Just spend all day, playing with the loop and getting it as high as possible, now apart from the side that runs around 6" from the side of the house, it's pretty much clear of everything, it's resonant on around 8.122Mhz, 16Mhz & 24Mhz, does that mean I would have to make it slighly longer to be resonant on amateur bands ? Would it REALLY be worth it though, it would take ages lol
The loop/square is at around 18ft at it's 2 highest points sloping down to around 10/12ft at it's 2 lowest points, will this be ok, how will it effect the angle of radiation ? It's sloping down towards the west/states lol
I'm just explaining what I've done and how I've done it to gain some pointers as to how I can make it better, or if I've done a resonable job
Also I put up a EWE antenna today for AM DXing, so simple to put up, anyone had any experience of using one ?

Thanks

Paul.

[Andy]

Hi again Paul.
To bring those frequencies down to the amateur bands without doing a major lengthening job, how about putting in a small adjustable coil in series? Get a metre of wire and wrap it around a bog roll or similar and stick it in. To adjust it, I'd use a ferrite rod slid in and out, but if you haven't got one you could put taps on the coil and use a croc clip to select the one that gives a match at the bands you want.
I love farting about like this.

[uksoundz]

Thanks, but I spent all day redoing it, and making it a little longer, but not long enough lol it;s now resonant on around 7.6mhz, never mind the atu sorts it out, and it tunes up on all the other bands except top band too.
I decided to get it even higher, so 2 points are around 17ft high, 1 point around 14ft and the last point is around 25ft, how will this effect the radiation patten ?
seems to be working pretty well, I get around 2-4 's' points improvements versus my vertical on receive.

[2E0JFS]

I know people like to knock the SRC stuff and its... success..

But this kind of blows me away to be frank.

That a shortwave handheld with a wire wrapped round a bedroom ... could possibly be better than a professionally produced HF Antenna &&&&& one of the worlds best small Yaesu produced transceivers just boggles my mind. To the extent where, frankly I just don't believe it.

Am I the only one that's thinking there might be a fault in your co-ax or its connectors?

My /p fishing pole is transatlantic in the sense that I have a logged conversation between myself and S.Carolina him using 90-100w and a dipole and me using a fishing pole.

Something else is surely at work here?