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sooby
28-07-2012, 03:18 PM
howdy,

I'm trying to hook up a UHF aerial and am only getting 4 channels showing as available, and all of those are unwatchable as it is.

I've made sure the aerial is orientated correctly, both pointing at source of transmission & aerial is orientated like an arrow pointing away from source when viewed in plan (top down view).

Is there anything else I can try before I call in the experts to fix it?

Anything obvious to try?

Reason this is urgent is I only have a few hours of sunlight left before I must put back the old analog VHF aerial.

Thanks

feersumendjinn
28-07-2012, 04:17 PM
Have you tried turning the aerial 90 degrees (so it looks like this from the side (<-x-x-x ..........transmitter) instead of the top (horizontal instead of vertical orientation))?
Where are you?, a location may help.
These guys may be helpful
http://www.nzdtv.com/forum/index.php?

sooby
28-07-2012, 04:25 PM
yup, tried that.

When it was looking like this in elevation <-X-X-X we received zero channels, then when it was rotated to look the same BUT in plan, we received 4 channels (well, it said we did however they are so distorted it might as well be static....)

feersumendjinn
28-07-2012, 04:41 PM
Are you talking digital or analogue signal reception (Freeview versus old system (no settop box/decoder involved)), if analogue you will need VHF aerial connected/mixed as well to receive all channels.

As well as that, analogue transmissions will cease this year or next (depending where you are), so if you are still using analogue, you'll need to update soonish (poss a good idea to get a professional aerial/system installer to advise/help you).

sooby
28-07-2012, 05:19 PM
Tivo unit is the tuner, it didn't' give me a digital or analog choice, I think its because tivo is digital only?

Aerial does have a splitter, didn't think it would make that much of a difference.

Also tried rotating in multiple directions, and double checked none of the outer strands or foil were touching centre prong.

I'm done - time to call in the professionals!

Thanks anyway everyone, really appreciate your help!

Billy T
28-07-2012, 05:54 PM
Tivo unit is the tuner, it didn't' give me a digital or analog choice, I think its because tivo is digital only?

Aerial does have a splitter, didn't think it would make that much of a difference.

Also tried rotating in multiple directions, and double checked none of the outer strands or foil were touching centre prong.

I'm done - time to call in the professionals!

Thanks anyway everyone, really appreciate your help!


Did you check the "district average" i.e. take a look to see where all the other aerials in your street were aimed? From that you can tell whether your antenna orientation and polarisation are correct.

However, the most likely problem is that you are trying to feed the TIVO output into a TV channel that is not yet tuned to the TIVO output, instead of using a TIVO AV output to feed an AV input on your TV. If so, then once you changed the antenna connection your normal reception went down the dunny.

I don't know anything about TIVO units but all my decoders have an AV output and the TV just acts an a dumb monitor. Took me ages to convince the family to use the old remote solely to switch on the TV, then to control everything else with the digital tuner remote.

Cheers

Billy 8-{)

sooby
28-07-2012, 06:18 PM
Thanks Billy,

But I directed it the same was as several neighbours and still no dice!

Yes, the Tivo is doing all the tuning and the TV is just a monitor - even then the tivo only picked up 4 channels (even tho they were all unwatchable, strange thing was the signal strength indicated was about 70-75%?)

At least I gave it a good shot, don't mind paying a pro now.

Thanks everyone

piva
28-07-2012, 07:02 PM
The end with the shortest rods should be towards the transmittion source. If yo do not have a free view decoder you will only see a couple of uhf analog channels. Also you need a better coaxial cable then for tv1/3 unless you are in a good signal area. i.e. can see the transmission tower. the antenna elements should also be horizontal. If they look like a wide "H" then they should be so that the H is onits side.
piva

howdy,

I'm trying to hook up a UHF aerial and am only getting 4 channels showing as available, and all of those are unwatchable as it is.

I've made sure the aerial is orientated correctly, both pointing at source of transmission & aerial is orientated like an arrow pointing away from source when viewed in plan (top down view).

Is there anything else I can try before I call in the experts to fix it?

Anything obvious to try?

Reason this is urgent is I only have a few hours of sunlight left before I must put back the old analog VHF aerial.

Thanks

sooby
31-07-2012, 01:48 PM
OK, now we are getting somewhere!

The father in law came round and pointed out the 20+ year old splitter was likely to be the reason I couldn't get UHF reception. (Seems I was so close but yet so far!)

I plan on buying the cable myself, (testing the aerial on the ground to make sure the aerial works first), install a new UHF capable splitter & try to get this going myself (worse comes to worse and I have to call in a pro to fix it all: at least I tried and have the gear to keep the costs down).

So I have a few questions before I start:

1/ Is there any reason to use a horizontal splitter over a vertical splitter apart, apart from the orientation of the cable outlets for mounting? (basically how do I know which one I need: horizontal or vertical?)

2/ How important is using a weatherproof cover for the splitter, if I intend to mount it under the house (protected from rain etc).

3/ I'm looking at getting quad shield cable, how much of an improvement is that over duel shield? Is it *really* going to be that noticeable?

4/ Can the UHF & VHF aerials be mounted on the same mast OK without interfering with each other? Was thinking may as well enjoy both (able to record more channels at once) until analog is cut off anyway.

5/ I've seen splitter refered to as 'power pass all ports' what does that mean exactly?


thanks

CliveM
31-07-2012, 01:56 PM
1. No
2. Not very
3. I would not bother
4. Yes

sooby
31-07-2012, 02:01 PM
thanks CliveM, appreciate your advice!

CYaBro
31-07-2012, 02:15 PM
Quad shield is only required if you are going to connect to a cable internet/TV service, for digital satellite or UHF signals dual-shield is fine.
Make sure it is Sky approved stuff though.

5. Power pass port means that if you have a satellite set-top-box connected to that port then it can send power to the LNB as the LNB requires power to work and to know which polarity to use (vertical or horizontal)
If you want to connect more than one STB then you usually need a splitter that has all ports power pass.
Not really an issue for UHF.

dugimodo
31-07-2012, 04:32 PM
Not much to add except the power pass through is also needed if you use a masthead amp like I do.
If you have a friendly neighbour with working freeview see if they'll let you take the TiVo over and plug it into their Aerial so you can confirm it's set up correctly.

Billy T
31-07-2012, 11:01 PM
The father in law came round and pointed out the 20+ year old splitter was likely to be the reason I couldn't get UHF reception. (Seems I was so close but yet so far!) 5/ I've seen splitter refered to as 'power pass all ports' what does that mean exactly? thanks

None of my splitters are officially "UHF", in fact most date back to pre-UHF days, and nor is my coax anything special. My UHF signal was poor on Prime (maybe because of those splitters) but ok on the rest and Freeview is fine on all channels/TVs, so much so that I've turned the distribution amp down to minimum power. UHF Freeview terrestrial should not be that hard to get, and if your system will supply adequate signals on the UHF analogue channels then it should be well and truly OK.

I'd pull the Freeview decoder from the circuit then hook the system back up for Terrestrial TV to see if that is working OK on the UHF channels like Prime. Doesn't matter how many channels you get, just one with average to good picture should be sufficient to clear your signal delivery system. If that works, the problem probably lies in your Freeview decoder or its set-up.

'Power pass all ports' simply means that if you have a back-fed masthead amplifier, the splitter will pass the supply voltage through on any of the output sockets.

Cheers

Billy 8-{)

gneill
01-08-2012, 11:28 AM
Don't forget that very soon, or now if you have Freeview, the only aerial needed is a UHF one, so there will be no need for a combiner or anything else.

apsattv
02-08-2012, 07:38 AM
Saddle clamp type diplexor/vhf/uhf combiners and splitters are the main culprits in many Digital TV reception issues.

Ditch the VHF antenna and any splitter or combiner and run 1 new quad core cable from antenna to wall plate or direct to the set.

sooby
07-08-2012, 01:59 PM
heres an update for those interested:

New RG6 cables & power pass splitter arrived last friday, installed all & found still no channels.

Determined likely cause was damaged aerial so bought a new aerial to check and BINGO! All channels received and the clarity difference is amazing!!

Now have so many hours of TV stored ready to watch, and I'm stoked it all finally works.

Thanks to all that offered advice, I really appreciate it - please let me know if I can repay the favour (house plans or renovation advice etc)

cheers again guys :)

Billy T
07-08-2012, 03:28 PM
Determined likely cause was damaged aerial so bought a new aerial to check and BINGO! All channels received and the clarity difference is amazing!

Well, that is a pretty rare occurrence, so it was a bit of bad luck for you. It probably wouldn't be the antenna per se, because apart from the driven element (the one with connections) the rest is just a passive collection of metal, but the balun interface to either the driven element or the coax may have been corroded or otherwise munted.

Enjoy your new image quality, I know we did when we shifted to Freeview, it was quite a revelation. The only drawback is the slow channel change, you can't surf between channels anything like as fast :D but I guess that is an issue with the decoder acquiring the next channel signal out of the digital gloop. I wonder if Freeview Satellite and Sky have the same delay?

Cheers

Billy 8-{)

Richard
07-08-2012, 04:03 PM
Sky HD channel change is about as slow to arrive as an English summer.

sooby
07-08-2012, 08:41 PM
Well, that is a pretty rare occurrence, so it was a bit of bad luck for you. It probably wouldn't be the antenna per se, because apart from the driven element (the one with connections) the rest is just a passive collection of metal, but the balun interface to either the driven element or the coax may have been corroded or otherwise munted.

Billy 8-{)

Thanks billy, but see the link below to read that the aerial problem was self inflicted!

http://pressf1.pcworld.co.nz/showthread.php?125833-Help-with-UHF-aerial-location-amp-solder-repair-please&p=1108436#post1108436

Billy T
10-08-2012, 12:02 AM
Thanks billy, but see the link below to read that the aerial problem was self inflicted!

Bugger............I thought you had fixed that part of the instal! So you had to buy another aerial just for that?

Cheers

Billy 8-{)

Nomad
10-08-2012, 10:55 AM
Rather than starting a new thread.
We have a VHF and we might be getting a UHF aerial (as we got a Sky dish for intl channels). Is there a guide on the net that you guys knows?

The cables are all there and the mast, do we just purchase a aerial kit and just slap it on, point in that direction?
We might need to troubleshoot a cable issue or something b/c the upstairs TV cannot get the VHF anymore but downstairs can.
What is the best way to split the signal?

We cannot really see the TV station where we are, the guys up the road uses a longish UHF aerial, the guys in front of us use a Array style one. Are the ones from DSE or Jaycar etc .. good enough?

sooby
10-08-2012, 03:09 PM
Bugger............I thought you had fixed that part of the instal! So you had to buy another aerial just for that?

Thought I did, but bought the new aerial to confirm. Turns out my soldering isn't that flash and that aerial is no good. New aerial was only $50 from Dick Smith (half price!) and was money well spent.

Will try to sell off the broken aerial & all left over parts to try to recoup some of the costs.

dugimodo
11-08-2012, 01:42 AM
You can buy inline baluns with two wires sticking out one side and a coax termination point inside a rubber boot. With a bit of ingenuity it could probably replace the bit you wrecked. Still at $50 for a new one I think you did better.

Winston001
11-08-2012, 09:58 PM
Thanks for a very informative thread. I've battled with Freeview terrestrial on three houses with varying results. At one place I bent the aerial up to avoid a shadowing house and that worked out well.

At the second place (Lorantz DV3T) Freeview worked fine...for a few weeks. Then it froze. Up to the roof in a cold southerly with light rain, tried to clean the aerial contacts which proved to be rusted - and promptly broke off. I gave up in disgust and purchased a Freeview Satellite box which worked instantly.

Third house: the Lorantz worked well until the tv was switched on next day with a frozen signal. Nothing would change that except pulling out the power cord. No On/Off or Reset switch. My family unanimously voted for a degraded analogue picture rather than one which freezes...and thus the Olympics have been a snowy fest.

So I'm a bit irritated and perplexed. The roof is high and steep so I've put off going up there. It may be that the aerial could be turned towards the transmitter, given that an adjustment worked on the first house. The aerial is 15 years old.

CliveM
11-08-2012, 10:40 PM
If the roof is that steep Winston it may be advisable to get a professional to risk his neck rather than DIY :)