Other SOTA sites: SOTAwatch | SOTA Home | Database | Video | Photos | Shop | Mapping | FAQs | Facebook | Contact SOTA

2m Halo Antenna


#1

I have just bought a Yaesu FT857D as previously I have had no radio to operate 2m ssb. My only vhf antenna is a Watson 300 co-linear which works well on simplex but not sure about ssb.
I don’t realistically have anywhere to put a 2m yagi up. however, I do have room for a 2m Halo antenna. Question is, will I notice a difference on 2m ssb with a Horizontal Halo, over the vertical? Does anyone have any experience, tips or pointers about using a Halo type antenna for 2m ssb?
I have seen at least one site with details about homebrewing a Halo from copper pipe. I am open to suggestions on other antennas, but as I said, due to trees, other antennas etc it is not possible for me to put up an antenna which needs rotating.
Regards to all,
Phil. m0vey


#2

In reply to M0VEY:
Used to use a 2m halo many,many years ago. I think that you will see an improvement over the vertical for 2m ssb (I certainly did). A better bet might be a pair of crossed dipoles.

73, Mike

PS I can usually hear you above my s7-9 noise on 5MHz HI.


#3

In reply to M0VEY:

I dont know if this is of any use to you, but Moonraker have a 2m halo reduced to £9.95 at the moment

http://www.moonrakerukltd.com/offers.php?offer=1


#4

In reply to M0VEY:

You can experience upto 30dB polarization loss between vertical and horizontal polarization. If you dont want to use a rotator then an omni-horizontal makes sense. The amount of polarization loss you experience depends on location and frequency. It is often masked in a town enviroment where scatter can occur from the many rooftops. However, in the wilds when contesting on 70cms, I have experienced a 70cms FM contact at about 90miles range that was s9+???db (the needle made a click when it hit the end stop of the FT736) when using a 19ele beam vertical but was undetectable on a 21 ele beam that was horizontal. If I hadn’t seen it for myself I wouldn’t have believed it. So some form of horizontal antenna must be an improvement!

Whether you want to buy or build is really down to you. I’m only using simple wire dipoles for my SOTA activation. I must to admit getting huge amounts of joy out of knowing I made all of it myself including the dipole centre, the shorting links and making so I can put it together in the wind and fog with gloves on. There’s not much to a dipole really, but the amusement factor does kick in when it works just like it’s meant to.

Andy
MM0FMF


#5

In reply to G4BLH:
Hi Mike,
After viewing the replies to my post & speaking with Steve, gw7aav last night I think I might be best to try a simple horizontal dipole first. A crossed dipole sounds good but the dipole will have the brick gable behind it & as such there is no room for another dipole or it would hit the house. thanks to all comments so far.
I usually hear you quite well on 5mhz also mike.
Regards,
Phil. m0vey


#6

In reply to M0VEY:

A pair of crossed dipoles and two feeders would enable you to cover all directions. A dipole should have more gain than a halo in any one direction (except where its null is of course). Mounting an HB9CV (two element phased beam) in your preferred direction shouldnt be too obtrusive either. about three times the gain of a dipole.


#7

In reply to M0VEY:

Many years ago I used to use a halo. It has a couple of dB loss against a dipole and although sold as omnidirectional mine had a definite null at one point.

I would suggest a turnstile as a good omni antenna, as used by many beacons! However the little portable quad sold by Sandpiper has a very small turning circle, smaller than a dipole, and if you can fit in a dipole you should be able to fit in this quad.

At one time I lived in an area where outside antennas were forbidden. The house was of modern construction with a roofspace full of trusses, but I found that with careful positioning I could just rotate a 4 el yagi between the trusses: have you considered an antenna in the loft? Mine got me a fair share of DX in openings!

73

Brian G8ADD