Problem with outside antenna positioning

aerospyke · **22nd May 2007, 03:05 PM**

Hey guys,

I have NO idea what section this would go into so i picked this one.... we had a small accident during the heavy rains and a a tree branch took down our aerial on the roof, ripped the cabling off it and broke the mountings too.

Since then i have taken the opportunity to recable it with better cabling from inside the wall to the antenna (RG6 instead of RG59), fixed the mounting and put it back up there, but there is a problem. I can only get SBS and ABC radio (ABC TV channels are picked up but are jerky).

Lots of reading most likely point towards the antenna positioning, its not pointing in the correct direction but i cannot find where it should be pointing. Anyone know of a website for suburban Sydney (parramatta area) that shows where the transmission towers are that i need to point my antenna towards to pick up TV?

Or any other ideas please let me know

logifuse · **22nd May 2007, 03:12 PM**

Hi Aerospyke,

You need to be pointing towards Artarmon/Gore Hill Willoughby. If you take North as 12 o'clock, you're probably looking between 2:30 & 3:30 (almost due East).

I'll try & make a Google map that will help.

Justin

logifuse · **22nd May 2007, 03:22 PM**

Aim for the arrow! It's right in the middle of the 3 towers.

Also, make sure you're getting the VHF frequencies for 7,9,10 & the ABC & not the UHF translators from Kings Cross.

ABC Television On-Air VHF 12 Hor 226.5 MHz ABC Tower 221 Pacific Highway GORE HILL
Seven Network On-Air VHF 6 Hor 177.5 MHz Ch7/10 Tower 192-196 Hampden Road ARTARMON
Nine Network On-Air VHF 8 Hor 191.625 MHz TCN 9 Television Tower Artarmon Road WILLOUGHBY
Network Ten On-Air VHF 11 Hor 219.5 MHz Ch7/10 Tower 192-196 Hampden Road ARTARMON
SBS Television On-Air UHF 34 Hor 571.5 MHz ABC Tower 221 Pacific Highway GORE HILL
Digital Forty-Four On-Air UHF 35 Hor 578.5 MHz ABC Tower 221 Pacific Highway GORE HILL

Justin

aerospyke · **22nd May 2007, 05:01 PM**

You are a legend, thanks mate, when i get home tonight i'll give it a burl, i printed out the page and hopefully it will not be a case of advanced geometry to get the angle right !!!

If that fails i may have to look at the wiring i did on the antenna itself, is there a way to test coax connections? at least with RJ11/45 u can test pairs, coax how do you do it?

logifuse · **22nd May 2007, 05:10 PM**

Quote:

Originally Posted by aerospyke

is there a way to test coax connections? at least with RJ11/45 u can test pairs, coax how do you do it?

Not an easy way that I can think of, but I doubt that's the problem. Visually, just make sure none of the shielding is touching the centre core (loose strands can easily get wrapped around when stripping). Particular frequencies can be affected by tight bends & the like, but as you're missing practically all the VHF frequencies, I doubt that's the case.

Did your antenna survive undamaged? How's the balun (the bit that connects the cable to the antenna)?

Justin

Edit: PS - what no thanks button love?

aerospyke · **22nd May 2007, 05:27 PM**

the balun was a tad bent but not damaged other than that... it has plastic parts that are that old that they are disintegrating and i'm hoping that they are not affecting anything

p.s. have a thanks button

p.p.s. one day i'll be thanked for something *thumbs up*

p.p.p.s. BTW love your avatar picture !!

logifuse · **22nd May 2007, 05:41 PM**

If you need to replace the balun (hopefully not), one of these is a good option: Jaycar F-Type Balun - it let's you use an F connector instead of saddle clamps.

Justin

PS: I see we've got the same mobo/cpu - what video driver are you using? I've just gone to 6.14.10.9420 (94.20 - not from Nvidia's site) & for the first time everything is smooth as (except ABC HD - I need to set PureVideo to Film to watch that). Also, what's your sound output like? Mine was a bit crackly/poppy with the onboard.

Thanks!

aerospyke · **22nd May 2007, 07:09 PM**

yay thanks for the thanks

well i repositioned the antenna to that area, with both the skinny end and the thick end (think pointy and flat end of a triangle if the imagery is failing you) .... but both ways i can only get ABC (ABC HD even works nicely).... but doesn't even detect the other channels.

EDIT: I'm using 93.71 drivers from the nvidia website, directly only using purevideo and it works quite nicely. the onboard sound hasn't given me issues, running from 3.5mm jack to 2xRCA to the TV using a HD signal. no sound degradation of any sort, but atm i'm only using low powered speakers. i got better stuff but it doesn't take digital and no amp yet

EDIT2: That balun from jcar looks interesting... how does it work? do i terminate the cable using an RG6 F-type connector, then wire that balun to the antenna, one wire being earth the other being the signal, and screw the two together???

logifuse · **30th May 2007, 01:58 PM**

Sorry Aerospyke,

I missed your last post.

Have you got things sorted yet?

In terms of the balun, your antenna should have 2 bolts halfway along (or at the end) that it attaches to. See this photo - it's the same type of balun.

Your antenna cable needs to be terminated in an F connector.

The skinny end of the antenna needs to point towards the towers by the way.

Justin

aerospyke · **30th May 2007, 04:20 PM**

G'day mate, no dice as of yet, the directioning didn't bring me any joy but i haven't replaced the balun yet. How will i know which wire is core and which is the shielding?

logifuse · **30th May 2007, 04:49 PM**

Quote:

Originally Posted by aerospyke

G'day mate, no dice as of yet, the directioning didn't bring me any joy but i haven't replaced the balun yet. How will i know which wire is core and which is the shielding?

Strangely, once you get to the balun, it doesn't matter. The legs are not electrically isolated from each other. Antennae are very funny things - quite often they work in a counter-intuitive way. You might think that all the elements are connected to each other (& the balun), but it's just the fact that they're physically there that counts.

It's strange that you're getting the ABC & not the other VHF channels. I'd run ScanChannelsBDA (choose any tuner it comes up with, select Aus & scan) & when it's done, look at the log file it leaves in the same folder as the app. You should see some action on the frequencies I mentioned earlier.

Justin

Percul8or · **30th May 2007, 05:55 PM**

I had the same problems. If you in a line of sight of the repeater towers at either Kings Cross or North Head get a UHF only antenna and point it at one of the towers.

This way you are sure to get the same signal strength from all channels rather than trying to point it in a rough centre of the main towers andgetting different signal strengths.

I got this on e-bay. Works well but not the best in quality.

http://cgi.ebay.com.au/BRAND-NEW-DIG...QQcmdZViewItem