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Best mutliband antenna for chasing


#1

My home-made fan dipole up 40’ does well … except for receiving QRP. So I have been shopping products and designs for a Multiband antenna for my home for chasing. I would value the comments and experience of my fellow chasers and activators. What have you had success with and what would you avoid? I use my KX3 at home with 100w amp. Our house is on a hillside in the mountains of NC with rocky soil. Thanks to all! Scott kw4jm


#2

If you can afford it, a multi band yagi of sorts. That will increase things for you. Even a 2 element homebrew pointed in your normal direction.

Malen
VE6VID


#3

I use a 40m loop


#4

Another vote here for the 40m horizontal full wave loop (aka Sky-loop). Cheap to make very low noise omni-directional on 40m, some gain on higher bands. Works on 40,20,10m without a tuner and the WARC and 15m band with one. (possibly also 6m but I have a beam for 6/4/2m).

Downside is you need space to put it up - ideally you don’t want it going over the house roof if possible.

73 Ed.

Or if you want to buy rather than build Scott (remembering you will still need to supply supporting masts) there’s this commercial product:
http://chameleonantenna.com/WIRE_ANTENNAS/CHA_SKYLOOP/CHA_SKYLOOP.html


#5

Hi Scott,
Your fan dipole is probably as good as it gets unless you have lots of space, significant finance and can put up a decent antenna farm. You don’t say what frequencies you are interested in.

I used to run a TH6 beam on 20/15/10 and it was very good even at a mere 40 ft. You can buy multiband HF beams with 3 to 6 active elements and they will outperform a simple dipole at the same height. Higher is better. The biggest ears have stacked yagis on 200 ft towers.

For 30 m, 40 m and 80 m you can get monoband beams but you will need a stronger tower for these. Probably best not to have more than 2 big beams per tower and make sure the system can handle the wind loads.

You could, if you have big acreage, put up 6 big Rhombics to give virtual 360 degree gain but again they need to be at 100 ft or so to work properly.

Expensive? You betcha. We all make the mistake of spending more on the rig than the antenna.

If the other guy is QRP on a peak best to first get a quiet QTH out of town. Put up the biggest antenna system the bank can buy for you. Operate a remote station.

Even a humongous antenna may not give much improvement in received S/N if your QRH is in the middle of suburban RF QRM hell.

My own set up is modest and I accept that I can’t work many activators because they are in the noise.

Good luck
73
Ron
VK3AFW


#6

The antenna that works for me is a G5RV set up as a doublet, tuned with an MFJ-949E versa tuner. This enables me to get 1:1 SWR on all bands 160 metres to 6 metres, and I chase successfully on all those bands except for 10 MHz (I don’t do CW at present.) My limiting factor is urban noise, which comes at me from all azimuths.

The only advantage a doublet has over a fan dipole is that a fan dipole for eleven bands might be a bit of a beast to set up, but the doublet does it with one wire. An antenna with gain will be better than a simple wire antenna but will be limited to one or a few bands.

Another possibility is two phased verticals that will enable you to switch the directions of the major lobes and give some gain.


#7

Another vote for horizontal loop antenna. Mine is a little shorter than 40 m wave lenght (space restriction, one leg over the house roof). It is made of 38 m long wire, 7 m agl and fed by 300 ohm twin lead cable, followed by a 1:4 balun and 2 m RG58 coax cable into my KX3. It is usable on all bands from 40m to 6m, KX3 can easely tune on all these bands. Not great DX antenna, but I have some DX activators and other stations from NA, SA, Australia etc in my log. It is very simple to build and it is worth trying if you have enough space.
Good luck with your new antenna,
73,
Mirko


#8

I actually use the same type of antenna for chasing as I do for activating:

It works well on all bands (WARC bands too when they are open). It is extremely simple to build and it connects at the end, thus offering all the benefits of a resonant end fed wire, minus about 4000 ohms impedance. Whilst I do not hear every SOTA op at home, when the bands are open I have worked plenty of DX with only 15w, so I have no complaints.
73 de OE6FEG / M0FEU
Matt


#9

IMHO you’ll be wasting your time trying to improve the fan dipole unless you can put up a yagi.

Barry N1EU


#10

When chasing, hearing the activators is also my weak link. I know that many other chasers are hearing much better than I. Due deed restrictions, the best I can do for a home antenna is a 40 meter inverted vee with apex at 35 feet and antenna tuner that allows me to work all HF bands. But I have found that my real problem is the local noise in my rocky one-acre Texas Hill Country suburban lot. I purchased a Timewave ANC-4 noise canceler which is inserted between the antenna tuner and transceiver and it has greatly helped with receiving. It uses a small antenna to sense the noise and a phasing system to remove it from the received signal. It does not perform this perfectly and it takes some tinkering with the noise antenna and how to use the device. But, I know that without it I would not be able to hear many of the activators that i do now.

73, Don AC7P


#11

This! Remove as much noise as possible before the RXer not with DSP filters after the weak signal has already been masked.


#12

I might be wrong but I think that this is a council of perfection which falls down if you suffer from multiple noise sources.


#13

sigh


#14

Multiple noise sources add linearly, so that isn’t a problem.

The position of the noise sampling antenna relative to the receive antenna can change the effectiveness. Changing position or changing frequency might require retuning the noise cancelling network. Nulling moving or changing noise sources will also need occasional retweaks.

wunder


#15

I have a European equivalent from RA0SMS (based on a German design I think) and now that I have two antennas up, I must get around to testing it!

https://www.eham.net/reviews/detail/13511

Not something applicable to activating but I’m hoping it’ll help during chasing. Switching between the antennas I can hear a station weakly on the loop but not on the end-fed, so if the X-phasing logic works, it ought to be possible to get rid of the common noise that is on both antennas leaving hopefully a clearer signal from the weak station.

Don, can you tell me - do you have to re-adjust the unit if you move a few kHz within a band or can it be set on one band and used there just by switching it in?

73 Ed.


#16

Ed - The Timewave unit does not require much adjustment with frequency changes. What i have found is that it is quite broad. Typically, I “adjust” the unit on 14 MHz and the same setting works just fine also for 18 MHz and 10 MHz. The “adjustment” involves starting with the unit off and noting the noise level on the S meter. Then turn the unit on (which inserts a loss) and increase the noise antenna gain until the original S meter reading is reattained. Then adjust the phasing for a null in the noise. For some reason (probably related to K6WRU’s comment) the unit does not work well on 7 MHz. There, the adjustments become overly sensitive and I typically find I have better performance with the unit off.

As for the MM0FMF and G8ADD comments, I knew when I posted my initial response that I was going to touch some nerves. I recall the subject of phasing system noise removal was discussed before. But it seemed there was no consensus if this was a worthwhile approach. Theory aside, the Timewave unit works for me and with the currently poor propagation conditions I would not be chasing SOTAs at all without it.

Don AC7P


#17

This! That’s why I think these units are worth trying out.


#18

WOW ! , After reading all the comments, I just bought one from HRO!
$ 189.00 and free shipping!

73 Gary N2ESE


#19

Good on yer Don - and thanks for your comments, it might just stir me up to try my unit out at last!

73 Ed.


#20

Radio Amateurs should not be buying wire antennae. They are easy to make yourself and cheap.
The question from KW4JM was about an antenna and not aids to reduce noise, so going off topic!!

For chasing a good all round antenna is an Off Centre Fed Dipole - known by some as a Carolina Windom. Has worked well for me ovet the last 18 months when I have not had an HF beam - problem soon to be remedied, so expect bigger signals from G4OBK on 20m and up soon.

I have used the 80m version since Jan 1st 2017. 80m length OCFD top into a 4:1 balun > 20 feet drop coax > to a choke balun and then RG-213 back to the shack. It just happens to fit into my back garden as the 80m version. A half sized 40m version should be used if you do not have the space. Look at the Chaser database. it works for me. Fixed into a beech tree 40 feet AGL at most. the short side is at 45 degrees, but it still works out fine business. The long side is almost horizontal at 40 feet from the beech tree to my house gable end.

From experience this is a better all round performer than the (obsolete in my opinion) G5RV.

If you want significant gain you are talking about a mast to support the aerial, for HF you probably need to buy need a multiband yagi, quad or Hexbeam type of antenna, a rotator and more engineering work. That opens up a whole new can of worms… Have you got the money, time and interest to facilitate that I wonder?

73 Phil