TV antennas--real numbers

in “the good old days” TV antennas could be compared by looking at the GAIN in DB. Today they are compared using the ‘undefined comparative’ better,hi-gain, fringe etc. OK so most folks live in the cities and if they get a picture all is fine—they pay what ever the antenna guy wants to charge. I’m a caravanner—a Grey Nomad and constantly visiting areas of the country that dont have city type coverage. Antennas for TVs can be ridiculously expensive and often not fit for purpose (I’m a retired communications engineer). $100s for a bit of wire in a plastic tube that’s no better than a set of rabbit ears. Without the ability to compare the gain of the devices there is no way to choose for most folks other than using the superlatives created by marketing.
A simple fit for purpose (on axis) gain number should be simple to produce. Or we start a movement to insist that manufacturers quote a gain figure.

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Thanks @grizzlyowl, great topic.

We’d like to hear more about everyone’s experiences with these type of antennas. Good experiences, bad ones, tips or tricks - please post below.

An example. the “Winegard Sensar III Amplified TV Antenna” ( https://camec.com/tv-audio/antennas-accessories/winegard-sensar-amplified-antenna-including-euro-jack.html)

Common on many caravans and Ideal for horizontally polarized VHF TV.

Unfortunately

  1. 45% of reception is vertically polarised.
  2. 87% of reception is UHF.
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There was a application for a HP41C calculator where you put in the wave length, and then the measurements of the directors and reflectors that gave a gain number. It only worked for Yagi antennas. must have a look at the apps for Android again as last time I looked there was nothing there. I had an old DOS program too somewhere.

I can’t help with recommendations for a mobile installation - tricky because you may need it to work with everything being broadcast in Australia.
For fixed installations, I would just like to note that in some densely-populated metro areas such as Sydney, you probably no longer require a TV antenna with UHF capability (since SBS moved to VHF). Might save you a little on your next purchase.

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That’s great for Yagi’s–but nowadays you are often dealing with unknown shapes, phased arrays and circularly polarised stuff encapsulated in a plastic non removable housing.
You can see I’m an old fart–It really used to be that all manufacturers stated the on axis gain for their solutions and often provided a polar plot. Now all we get to compare one solution to another is superlatives.

Thanks for that—I think you have just pointed out why vendors can get away with superlatives instead of facts since most of the population lives in the cities where often you can get signal on a bit of wet string.

check out this site, they do give F/B gain

http://www.accessantennas.com.au/perth-discount/antenna-products/tv-antennas/high-gain-hg628-made-in-geelong-australia-digital-tv-antenna/

Yes. Thanks. Now all we need is to be able to compare this to others. In this case i have an advantage since being a retired comms engineer. The antenna shown is obviously a phased array with specs relatively well known to me. For those without my background its really hard to compare objectively. Even i have issues trying to compare the phased array or a yagi to something like https://camec.com/jack-digital-hdtv-replacement-antenna.html

Even people in cities need to have good reception. Where we live good old Aunty has appalling transmissions coming off an old low power transmitter that is in line of sight. The transmissions dribble to a stop in stronger winds, not to mention severe weather. :leaves:

I wrote to them to ask what the problem was, and say we were reliant on them for emergency warnings like tropical cyclones. They replied that we shouldn’t rely ABC TV, but should rely on ABC radio. :open_mouth:

On advice from a local TV antenna business we upgraded our antenna to a very expensive one. No idea of the specs, but it didn’t help. Can’t look for a ‘better’ one as we don’t know what the specs of this one are. :unamused:

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Exactly the sort of issue I’m talking about.
If its line of sight a multi-element yagi suited to the frequencies you need. Either VHF or UHF.
UHF antennas are probably more stable in high winds since they are smaller.
Long Yagis have a high gain and shouldn’t be expensive. One of the other responders here (Pandrew3) has a link to a phased array. They can be had for as little as $38.
Whatever you choose might need a mast head amplifier which can add another $100. Usually worth it in fringe areas though. Good luck

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Digital reception in Fremantle is problamatic because it is over the brow of the hill towards the transmitter. I don’t know about strong winds but cold weather definitely affects reception. Neighbours are being sold multi-element dual uhf vhf yagis which are more expensive than a good quality UHF antenna which is what is required. Hills do one for about $200.

Hi, I have to agree the new antenna descriptions are confusing. When I last purchased an antenna I purchased the more expensive Fringe antenna. My thinking was that this is the best antenna and should not give me any trouble. The antenna has been good but if the definitions/descriptions of antennas were easier to compare and if there was little difference in gain between antennas then it would be much easier to select an appropriate antenna and not just purchase the more expensive antenna.

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The last Antenna guy we had out said (the opposite of the previous guys) that our signal is too strong, not too weak.

He said that this is as bad as too weak a signal. If it’s too strong, it causes the channel to drop out just the same. So he sold us a signal damper. Still fiddling with the damper setting as the signal strengths seem to go up and down a lot.

Without all the information about the antenna, and the reading from meters it is impossible to know who it right.

Yes–when the prices can vary from $40 to 300 it pays to have objective information.

That can be true. If you have too much signal adjacent channels can cause issues But would have thought a bit of wet string might be cheaper than an antenna with a damper. Yes without the antenna specs( you might not need one) and possibly a signal strength meter you can’t decide who is right.

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Just composed a 2 page document with drawings and pictures. Its in word or PDF. Unfortunately I cant upload it :(.

That can be correct if you are too close to the transmitter or You have too much amplification.

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You could do screen grabs of the pages, or convert the document to an image format, then they could be posted in here.

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I’ve lived in a couple of low signal areas back when there were programmes worth watching on the tele, but for the last 10 years made do with no antenna at all :wink:

Try here for size - not all models have full specs but the few I looked at did:
https://www.hills.com.au/c/products/comms_products/antennas
(I have had no connection with this company since the early 80’s for a holiday job stamping out yagi elements for their UHF models, among other things).

In the past I’ve gone with separate units for VHF and UHF with good quality switch switch - a friend had similar with a small rotator for van use mounted on the a-frame and a pivot/lever arrangement to change polarisation if needed.

I’ve never been a fan of the one-size-fits-all - I’d prefer a Yagi or Quagi for each frequency needed, but that’s overkill of course - but the other end of the game is often the LPDA for VHF with a Yagi out front for UHF all on the same feed line which seems way too compromising.

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