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Get The Best Reception - Melbourne


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#876 GrantCC

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Posted 30 April 2015 - 08:01 AM

grant,

its all changed again since restack and 4g lte, the quality and effectiveness of the products you use can make a significant difference to your signal quality. post some pictures of your antenna / amp / power supply!

the andrew lacey you mention may be a lacey by name but as they don't install I doubt he represents them.

Thanks for getting involved guys. I can't see how to add pics to this forum, but here's some on my Flickr account. https://www.flickr.c...57651855799968/



#877 I am not a duck

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Posted 30 April 2015 - 11:14 AM

Clipboard_2.jpg

 

 

There ya go!


Edited by ------, 30 April 2015 - 11:20 AM.


#878 alanh

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Posted 30 April 2015 - 08:19 PM

The outside photo does not show the amplifier mounted 1 metre under the antenna, so it gets a much stronger signal prior to amplification. This reduces the noise in the signal which causes signal breakup.

The angle of the shot does not show what type of log periodic antenna it is. I need to see the relative lengths of the elements. It looks like a UHF log periodic. The amplifier is for UHF and has a low gain at VHF and purchased from Jaycar, so the antenna should be pointed at Arthur's Seat?

 

Log periodic antennas which is what the photo shows has a wide channel range but as a result have lower sensitivity to a small number of channels.

 

 

Two Bays Rd is low signal from both Mt Dandenong and Arthur's Seat. So you need to try a 10 element  (http://www.jaycar.co...ELEMNT/p/LT3165 or more sensitive 14 Element Yagi mentioned above for Mt Dandenong, you will have to replace your amplifier . The Jaycar specifications are contradicting one specifications shows gain 10 dB VHF. I can't find the image on the Matchmaster website to find the real specifications. What is the Matchmaster model number? Replace it with a http://www.jaycar.co...ilters/p/LT3251 Manual https://www.kingray....35FS_IM_web.pdf Use the VHF input for Mt Dandenong and the UHF for Arthurs Seat. Do not use separate not combined input.

 

Alanh



#879 dig2all

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Posted 30 April 2015 - 09:10 PM

pix noted. you're behind mt.eliza, with best results from mt.tassie? your antenna is a wideband uhf fracarro lp45f, good as logs go but now that mt.tassie has restacked into low band4 you could get another 6db or so more signal from the right antenna. that could make a significant difference. your amp is probably ok unless you have lte4g interference. a filter before the amp might also help, or a properly filtered amp (the device you have is not). I hope you can make some sense of all this, you are in a tough spot where you would benefit from an experienced installer.

#880 GrantCC

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Posted 01 May 2015 - 06:51 AM

Great! Thanks for all the advice guys. In fact I spoke to my neighbour yesterday who told me his installer took two days to get a signal, so the advice about an experienced installer would be correct. He's now very happy with his phased array antenna pointing to Arthurs Seat.

 

Regards

Grant 



#881 I am not a duck

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Posted 01 May 2015 - 09:22 AM

low band4 you could get another 6db or so more signal from the right antenna

 

I'm not aware of a benchmarked domestic TV antenna (single unit, not stacked) with 17dB or so of gain (either dBi or dBd) at the frequencies of interest.

 

Perhaps I can be educated?



#882 alanh

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Posted 01 May 2015 - 12:58 PM

Log periodics have low gain particularly at UHF. Facarro LP45NF maximum gain 11.5 dBi

 

Instead of using antennas designed for (470  - 862 MHz) Au channels 20 - 75 = Eu channels 21 - 69 (Au channels are 7 MHz wide 51 and Eu 8 MHz) use one for the specific channels on a transmitter site (restack has now made them consecutive channels)

Latrobe Valley block B 526 - 568 MHz channels 28 - 33 means all the elements and their spacing can be optimised for those wavelengths. The LF45 has to have shorter elements for the higher channels which pick up little of the block channels required.So most of the antenna is not used in a specific installation.

http://www.hillsante...&ProductID=5028 is an example of a Yagi-Uda antenna for channels 28 - 33. All of its elements resonate within the the design frequency range.

Its specified gain is in dBd so to compare it to European antennas add a little more than 3 dB.

 

4Bay phased arrays can also get gains of 17 dBi, however all the commercial ones are wideband. If the X dipoles were replaced with resonant straight line types and the spacing to the reflector optimised their performance a the wanted frequency would also improve.

 

There is another trap with specifications. The compare the signal level for a dipole at that wavelength to the antenna at the same wavelength. So the lower the frequency the longer the dipole the greater the signal if the transmitted field strength remains identical. This is why VHF antennas only have a small number of directors compared to a UHF antenna.

 

As for benchmarking http://www.cai.org.u...hmarking-scheme you will note is a UK organisation. The UK does not use Band 3 for TV, they are having a restack also but because of the 8 MHz wide channels their transmitter channels are not completely sequential. Also they use 470 - 526 MHz for TV we use it for two way radio including UHF CB, and 694 - 862 MHz where as we use it for mobile broadband and not TV. The UK's restack is to remove their TV from 790 - 862 MHz for mobile broadband. So all in all the UK benchmarking is not appropriate for Australia. We need the new Australian Standard 1417 http://infostore.sai...oductID=1736091 to be released.

 

Alanh



#883 Kewvic

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Posted 04 September 2015 - 06:12 PM

Hi,

I' m in a spot of reception bother and would appreciate any help.

Approx three weeks ago we started to get pixalation on ABC2 and, to a lesser extent pixalation on 10. The PVR (Topfield TRF 7260) showed a small loss on the signal coloured bar and a large loss on the quality bar

I spoke to the ABC who said that 1. they had no altered transmission 2. that as it was also occuring on 10 that it was probably our antenna which may need to be replaced. They suggested that I should first reset the PVR  to factory settings to see if that solved the problem. I reset to factory settings - no change.

 

I emailed Hill Antennas, gave them my address and they recommended the Tru Band Metro Plus Black Arrow- FB608582 which I bought and installed today. The result was that I now lose the signal and quality bar every 25 seconds for a period of approximately 2 seconds - ie, the picture freezes for 2 seconds every 25 seconds.

 

We have not introduced or changed any electronic device in the house in this period.

 

In my ignorance I conclude that the new antenna is inferior to the original, and that 'something' external has started to transmit/ interfere with our signal but I have no idea what!!! Can someone offer me hope?

Cheers
 



#884 alanh

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Posted 16 September 2015 - 03:59 PM

Kew,

Was this installation done by an antenna installer or yourself?

Is this faulty reception continuous over 24 hours or does it only occur at particular times of the day?

Which street in Kew are you in? There are some areas of poor reception in your suburb. There is coverage of your suburb is not only from Mt Dandenong, but also from the Como Centre in South Yarra and from the Rialto tower in the CBD.

 

Alanh



#885 andrewlace

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Posted 18 September 2015 - 08:16 AM

A fair number of customers in your area through the years have wound up getting tv reception off the channel 10 building. Because of the introduction of lte I'd be trying an old school narrow band yagi 10/4046/r yagi these can be mounted vertically polarised without extra hardware. If you have an amplifier you may need lte filtering as this has become a recent issue everywhere. If you do need an amplifier any of the Kingray mda series amplifiers are the best I've used: most headroom, least noise, most effective on weak signals, most impervious to interference.

#886 alanh

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Posted 18 September 2015 - 10:10 PM

Kew,

For South Yarra (the Como Centre, where channel 10 studios are), you need to rescan the receiver with no antenna connected to erase any existing channels. Then insert the UHF antenna cable and manually scan for the following channels: 40, 41, 42, 43, 44 and 45

All of the transmitter sites I mentioned except Mt Dandenong are best received with a UHF phased array, because they are directional beside the antenna which the Yagis are not,  in vertical polarisation.

The MDA series of amplifiers are not a good choice now because there is no filtering to remove LTE mobile phone transmissions. The MDA20L should be removed from the market unless it is used for amplifying FM radio signals.

 

It is probable that no amplifier will be required if you use the South Yarra translators.

The MDA series of amplifiers are not a good choice now because there is no filtering to remove LTE mobile phone transmissions. The MDA20L should be removed from the market unless it is used for amplifying FM radio signals.

 

It is probable that no amplifier will be required if you use the South Yarra translators.

 

Alanh


Edited by alanh, 18 September 2015 - 10:14 PM.


#887 andrewlace

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Posted 24 September 2015 - 11:48 PM

Kewvic that antenna is designed for mount Dandenong, not the channel 10 building. Which transmitter are you pointing towards?

#888 beeblebrox

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Posted 07 October 2015 - 06:26 PM

 

The MDA series of amplifiers are not a good choice now because there is no filtering to remove LTE mobile phone transmissions. The MDA20L should be removed from the market unless it is used for amplifying FM radio signals.

 

It is probable that no amplifier will be required if you use the South Yarra translators.

The MDA series of amplifiers are not a good choice now because there is no filtering to remove LTE mobile phone transmissions. The MDA20L should be removed from the market unless it is used for amplifying FM radio signals.

 

 

The new MDA amps have LTE filters built in.  They also now produce a B3 VHF only model . And a UHF 470-694  They continue to be some of the best residential amplifiers on the market.



#889 andrewlace

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Posted 11 October 2015 - 09:28 AM

Thanks for posting that beeblebrox. Have you used many of these? I've still got a few mda20 series left. I've never seen an amp in this price range work as well. I'll have to see what to do when I get down on levels. External filters work great too.

 
The new MDA amps have LTE filters built in.  They also now produce a B3 VHF only model . And a UHF 470-694  They continue to be some of the best residential amplifiers on the market.



#890 I am not a duck

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Posted 11 October 2015 - 11:50 AM

External filters work great too.

 

I've seen this as a suggestion for non LTE filtered mastheads: (Image is of an LTE filtered masthead.)

 

228edb6b-6ace-4c47-9534-ed1ff80b135b.jpg

 

Not sure how well that is going to work, 'cos I'm pretty sure the compression connectors I use would not allow the cover to close. (I use FAE60s anyway, or change out the masthead if it's really old.)

 

(OT: Are you the same person with the Westpac payway issue? Did you get it working in the end?)

 

Edit: FWIW, kingray also have screw/saddle mastheads with LTE filtering.


Edited by ------, 11 October 2015 - 11:54 AM.


#891 handofcod

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Posted 15 November 2015 - 03:28 PM

Hi guys - hoping someone can help to decode my vey strange experiences. The problem is that all ABC and Channel 10 related channels have dropped out. Sometimes ABC1 is non-existent, sometimes scambled. Channel 10 worked until recently when I retuned the TV and has now dropped out completely.

 

I'm in Kensington and have had perfect reception at the address previously. We were watching the ABC news when it literally went black and has never recovered. I can't explain why it worked just fine before but has now disappeared. Got up on the roof and checked the antenna, everything is connected just fine, got into the roof space and checked the splitter, everything is fine. All other channels work flawlessly.

 

Any ideas what I can try? I have no idea if it's the antenna - I presume it's fine since it worked previously and the other channels work too. Possibly interference from some other broadcast maybe?



#892 handofcod

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Posted 15 November 2015 - 03:33 PM

Well this is embarrassing. I can't seem to edit my post above. I tried doing something I saw online. I seem to have fixed it. Had to pull the aerial cable out and go through the retune process on the tv, then try again with the cable plugged back in. Now everything seems to have come back.... Weird!



#893 beeblebrox

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Posted 25 November 2015 - 10:24 PM

Thanks for posting that beeblebrox. Have you used many of these? I've still got a few mda20 series left. I've never seen an amp in this price range work as well. I'll have to see what to do when I get down on levels. External filters work great too.

I've used a few now... not doing a lot of antenna work at the moment when I do it's mostly 5wire.  The only thing I don't like is the MDA15V isn't fully shielded.....  but still very low noise and also has a gain control and lte filtering...very useful for MT Dandenong jobs where the customer has lots of points....   Am using the Alcads with built in LTE for UHF.



#894 andrewlace

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Posted 29 November 2015 - 01:41 PM

Oh dear I went out there over 18 months ago so it wasn't lte that was the issue. I was there for about 15 minutes and never charged for my time. Grant is in an area known by locals for for being difficult. A lot of the homes are built on the side of a hill. LTE is an issue, not the issue. Kingray do not filter out cb bands on all their amplifiers. I know this as a lot of pubs use their amps to run s band analogue. You should run a noise gen and spectrum analyser to test a product before declaring then effective as filters. I have said it before narrow band yagis are a great cost effective way of filtering lte, cb radio and most interference. A wideband uhf yagi or log periodic is not advisable. Most filtered lte amps are greatly inferior to many dedicated lte filters on the market. That said agreed it is not wise to rehash don't use a log periodic, use a lte filter, trust me on the sunscreen speech. Kingray make some excellent amplifiers but filtering out anything out of the tv band magically and with low noise, even their budget products, that they don't do so well. As previously discussed the mda20 is vastly superior but with little or no filtering. Melbourne doesn't use block e so a narrow band yagi can smash most lte issues. We need to remind ourselves that a lot of issues are resolved with the correct antenna and no amplifier. A cheap amplifier and antenna is an expensive solution to a simple problem. Most interference issues can be resolved by removing amplifiers and installation of a suitable quality antenna. As I saw earlier with a chap trying to get Melbourne cbd transmitter off a terrible combination antenna polarized horizontally (cbd needs 40-44 vertical from memory). It would be cheaper and simpler to put a narrow band yagi on designed for block e 10/4046r does an awesome job at this and can be used for either polarity (oddly enough I used to use these for Gippsland back in the day). With grants place someone needs to do a full site test. Grant was keen to point out access issues, as with anything if you can't safely get to the masthead amplifier and aerial you don't do the job. That's how you stay in the industry. What was wrong on Grant's job is an issue of conjecture until someone gets access abc fixes it. This may have already happened (could have been an intermittent amplifier) as is often the case. Half the sites on the peninsula with amplifiers use alcad am126, a product which is legendary for going intermittent after a few years. I'm an active forum member and have been for years.

#895 andrewlace

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Posted 29 November 2015 - 01:47 PM

I've used a few now... not doing a lot of antenna work at the moment when I do it's mostly 5wire.  The only thing I don't like is the MDA15V isn't fully shielded.....  but still very low noise and also has a gain control and lte filtering...very useful for MT Dandenong jobs where the customer has lots of points....   Am using the Alcads with built in LTE for UHF.

Hi beeblebrox, yeah I like the cast casing on the old mda20. I've seen a few pcb only Kingray's fail due to corrosion. It's an expensive case to manufacture though. I know almost every amplifier has the same issues unless you go nuts with silicone lol. Which alcad are you using?

#896 I am not a duck

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Posted 29 November 2015 - 05:48 PM

Half the sites on the peninsula with amplifiers use alcad am126, a product which is legendary for going intermittent after a few years. I'm an active forum member and have been for years.

 

I have installed hundreds 738 of these between 2000 - 2012, & only found ones with a 2003/2004 date code that fail when cold. I'm still coming across a few of these.

 

I also replace AM126's that fill with water when the mounting strap fails, or when LTE interference problems arise.

 

I stopped using them about 5 3 years ago & only use Kingray now.

 

 

Edit: Corrections.

 

 


Edited by ------, 30 November 2015 - 09:37 AM.


#897 andrewlace

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Posted 29 November 2015 - 06:01 PM

Yeah I'm on the peninsula replaced a 5 year old one a week ago. There are heaps of them here. Every time someone says it goes nuts at any time, amp is an am126 on the mornington peninsula they were a best seller. I want my installations to be working when I can't.

#898 andrewlace

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Posted 29 November 2015 - 06:01 PM

Yeah I'm on the peninsula replaced a 5 year old one a week ago. There are heaps of them here. Every time someone says it goes nuts at any time, amp is an am126 on the mornington peninsula they were a best seller. I want my installations to be working when I can't.

#899 wally3218

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Posted 25 January 2016 - 09:05 PM

I've just changed my old analog TVs antenna to a new digital ATV24DIG - Combination (Digital only) our replacement for Hills SMX24B4+ Coax is the old RG59 am looking at replacing it to RG6 later on.
Am in Bell Post Hill 3215 and the antenna feeds 3 TVs .
Every now and then at different times of the day and night I loose signal for channel 2 and 9
Am thinking of trying a higher gain antenna like the ATVD18 18 Element Band 3 (Digital ONLY VHF) not worried about channel 31
Would this antenna be a choice than using a masthead antenna or splitter amplifier.
Any suggestions welcomed , I know I should find a antenna installer with a meter , I'm a sparky and can run the cables first.

#900 Tazzy2Heads

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Posted 27 January 2016 - 08:51 PM

Hi Wally

You really need to measure the signal levels to know where you are at with the trouble channels.

An adjustable masthead amp is the easy fix to try first, quite often they will bring the quality up with the signal strength if the signal is not too low to start with

An 18 element band 3 antenna is a monster, remember the more elements the sharper the pickup lobe is and sometimes that can work against you.

I doubt whether I have bought 3 of them over the years here in TAS.If I can't make it happen with a 10 element antenna I go looking for a better location with the meter.There is not a lot of gain difference between an 18 and a 10 element antenna I have found and it's not generally showen up on all the channels.You will get a lot more gain from an amp 20+ db depending what you buy and  to make sure it's adjustable may get you out of grief.

Your existing antenna may just need to be repositioned to a better signal location for whatever channels you are watching now whether VHF or UHF.

cheers Tazzy