TV Antenna Feedback

[Chuck Baier]

My old Datronics TV antenna is nearing the end of its life after hanging on the top of the mast for over 9 years. So i would like some feedback from anyone that has a working unit that they are happy with and why. We often operate in fringe areas. Many thanks in advance.

[s/v 'Faith']

Ok, this is one of those posts that does not really answer the question... but I wanted to put it out there anyway...

I purchased one 'flying saucer' type antenna, and got another one given to me. I never installed them because I could not find a good location on my boat.

I then got an antenna from a friend, it is nothing more then a 36" loop of copper solid strand wire on a long batten. Each end of the wire is looped to one of those impedance matching transformers (you know the little thing with two wires that connects to an older TV).

I run regular cable from that to my small LCD TV.

I mention this because I can get more stations on that then any of the three dock mates with the pricy antennas. One of them found out they actually get better reception with the 'amplifier' for their antenna turned off.

Might be worth looking into, if it does not help you maybe it will help someone who reads this thread.

Good luck in finding the antenna that is right for you.

[Alan Wheeler]

One of them found out they actually get better reception with the 'amplifier' for their antenna turned off.

Just to address that one first, then your Mate has a seriuose fault, if we leave out the gain that the amplifier has, plain and simply put, the amplifier switched off affectively disconnects the arial part. So the signal is coming into the system from elsewhere.

Yeah I have had big issues with Marine arials as well. I live in a place with many hills and any boat anchoring or mooring position is usually hidden from a coverage pattern. When you do get something, it is often a bouncing signal and this can cause a lot of ghosting issues. If you are under a hill side and have a good "view" of a signal, then the signal will also bounce off the hill and also give you Ghosting issues. Unidirectional arials are majorly prone to ghosting. Also because they are unidriectional, the have poor directional gain. So a directional antenna, such as you would have on your house, will be far supperior and will be better at pulling in week signals with far less Ghosting issues from behind reflective sources.
The other issue with Marine units is that many are polarized in Horizontal only. Many signals can be both. Especially here in NZ when we have som many small repeaters around getting into all the nooks and crany's of the country. So as one signal of same frequency does not interfere with the same freq in another part of the country, the same siganals can be polarised both horizontal and verticle. So the antennae pick up pattern has to be spherical. This reduces there pick up ability even more.
The only real solution to the issue is to go satillite. But that is so expensive, it is far beyond most of us and you have to weigh up the need for TV against the cost. I love watching a few programmes and would love to have satillite, but it is too far out of reach and need to spend that sort of money, so DVD is the form of entertainment for us.

[Wahoo Sails]

I have had several different TV antennas, From the Datronics to the top O' line amplified Shakepeare model, none worked worth a crap. Someone once asked me "are there a lot of masts around you?" Duh. Seems that's part of the problem. I did what I consider the smart thing to do and deep 6ed the TV! Never been happier!
Bob

[coot]

Originally Posted by s/v 'Faith'

I then got an antenna from a friend, it is nothing more then a 36" loop of copper solid strand wire on a long batten. Each end of the wire is looped to one of those impedance matching transformers (you know the little thing with two wires that connects to an older TV).

I have a similar antenna, but fixed to the top of my mast. It is good enough for medium to strong signals. It isn't going to work well for weak signals, but neither will the alternatives. Practically speaking, you can't put a directional TV antenna (like you would use on a house) on your boat and still keep it pointed toward the transmitter as your boat swings at anchor. Well, if you have a mega-yacht you could...

The polarization problems that Alan mentions don't apply in the US because the commercial TV stations are all horizontally polarized.

In theory, they respond equally well to signals from all directions. (Alan is saying "unidirectional"; the common term in the US is "omnidirectional". Do you live in "a flat" or "an apartment"?) In practice, I find some variation as my boat swings at anchor.

Ghosting varies from place to place. Either it is going to affect you or not in a particular area. The only way to fix ghosting is to use a more directional antenna, then you're back to trying to keep it pointed the same direction all the time.

[Chuck Baier]

Thanks, guys the info is always appreciated. Helps to add to the knowledge bank, but I really would like some comments on specific models that folks are using and OK with.

[Alan Wheeler]

Chuck, I guess what we are trying to say in all the above is that we have used many and none are worth a damn. I have used several and all have performed equally as well....errr...badly. It is the nature of how they work that makes them not work. The pattern is Omni (sorry Coot, Omni is the correct word indeed) so this means they have little gain. A directional antennae has substantially higher gain in the direction it is pointed due to the design, which is number of elements in the arial. The directional arial does not pick up signals that enter from the rear, so you do not get ghosting issues the same. Omni means it picks up equal signal energy from all round. The more chance of recieving a reflective signal, the more ghost appears.
If you want good reception, you need to go Satillite. Satillite should be available in the US for around the US$1000 mark for the cheapest and they go up from there dependign on quality of tracking you require. The real expensive ones can still lock a statillite even at speed in ruff seas. The cheap ones will handle a boat at anchor in most situations just fine.

[Chuck Baier]

Allan, No plans in the budget to spend $5K for TV and that is what you would need to spend for a decent system. We have satellite at the dock but underway it is too expensive and not practical for sailing. Once you are south of the latitude of say, Brownsville you are behind the footprint and the unit is worthless.

[Alan Wheeler]

Not sure where Brownsville is, but I had been wondering just what part of the world is covered.
Yeah at $5K, you have to be real keen on TV eh.

[bill good]

This works for me in Aust. I am using the VHF radio aerial on a 46' mast thru a $60.00 set top box & with this digital sig no ghosting or fading just bute pictures. (Did put another VHF on the back rail for coms). It beats any results I've seen on other sail boats!!

Bill Goodward

[Chuck Baier]

Bill, How are you connecting the VHF cable to the TV?

[Alan Wheeler]

But I am assuming you have land based Digital Transmission?? Don't tell me....ummm actually it would be great if you tell me you are picking up Satillite Digital via a VHF arial.

[bill good]

Chuck, I use a coaxial switch to select between the VHF & set top box. Out of the set top box is the video & sound sockets which is meant to go to the TV via the "red, white, yellow" video /audio connection. I used a cheap 2.4Ghz wireless audio/video instead of running cables. To test the signal without going to the expence of a coaxial switch you can get a PL259 joiner & wire a PL259 plug to the set top box.

Alan, Correct This is a digital land based service which is ran in parallel with the anolog TV service here in Aust.

Note- I have disregarded the polarization of the signal & the fact the whip is not cut to the exact frequency but the height of a mast gives good field strenght & that is all that matters & it is very convenient.

Regards Bill Goodward