24 replies to this topic

[svh60]

Have just installed a new HD TV and am having some issues with reception. I am, in theory, in line of sight of the Orford transmitter but actual sight is blocked by several large trees and probably a house. Channels 2 to 60, with the exception of 5 TDT-SD and 50 ONE HD, give good reception most of the time. However when there is wind or rain all channels suffer from pixelation to some degree. Tonight it is very windy and even channel 20 ABC HD is for the first time showing some pixelation.

Whilst the TV tuned 5 TDT-SD and 50 ONE HD I cannot receive any visible signal.

Channels 62 7TWO, 80 WIN HD and 88 GO TAS suffer from pixelation and chirping sounds even without the wind, tonight with the high wind they are not watchable.

From reading this forum it seems I should ensure that the antenna is optimum before looking at masthead amplifiers.

Can anyone suggest what would be the best antenna for my situation or for that matter anything else I could do to improve reception?

[Alista]

svh60,
What is your analog reception like?
It's possible you have the wrong antenna as analog is on band 5 and digital is on band 4 and the bottom end on band 5. Do you have a picture of your antenna?
Also check all connections for corrosion and make sure you are using 'F' connections and not the old Screw and saddle type.

The Fracarro Log Periodic band 4/5 model antenna is suitable for your area. Model Number LP45F, available from Active Electronics Components Hobart, 320 Elizabeth St.

Edited by Alista, 02 January 2010 - 09:01 PM.

[alanh]

SVH60,
I suggest you read Get the Best Reception, Regional Tas and read the links.
Do not buy the Fracarro Log Periodic band 4/5 model antenna it is not suitable for your area. Model Number LP45F I say this because the Orford transmitters are vertically polarised.
In the above post click on the V4+ link. Fracarro make phased arrays.

AlanH

[M'bozo]

svh60, on Jan 2 2010, 09:17 PM, said:

Can anyone suggest what would be the best antenna for my situation or for that matter anything else I could do to improve reception?

svh60,

For a similar low powered vertically polarised translator I install antennas for in the North end of the island, when there is no blocked path to the transmitter site, I use Fracarro LP45F's, as Alista suggested. (Any Australian made band 5 antenna would ordinarily do, as Moreys Hill digital is all in band 5)

When there is terrain or trees in the way, my choice is a Fracarro PU4AF, or ALCAD AP369, usually with a masthead amplifier. Again, most phased arrays would be suitable.

As has already been suggested, ensure your current reception set up meets industry standards.

If your TV is one that is capable of displaying reception parameters (ie signal strength/quality), these can be used as a guide. Even though these indicators are not necessary accurate to any traceable parameter, they can be useful within themselves.

The only way to determine the correct antenna is usually by a site test with a number of antennas to determine the most suitable one, particularly when there are trees between you and a low powered transmitter site. Positioning the antenna is the most important parameter, in some cases this can be other than on the roof of the property. This testing will also indicate if a masthead amplifier is required.

Interestingly, when faced with situations such as yours, it helps if it is windy when the site test is performed. This can aid with locating the antenna for minimum interruption to signals, which sometimes can not be avoided.

Marc.

[svh60]

http://www.dtvforum....=new_post&f=145

Thanks for the responses, they are really appreciated however they have raised further issues. If I have posted correctly a picture of my current antenna should be attached.

According to the reception strength indicator on my HDTV channels Channels 2 to 34, with the exception of 5 TDT-SD and 50 ONE HD, give full signal strength. Channels 60 to 88 give around 3/4 strength. Channels 5 TDT-SD and 50 ONE HD give no signal.

Analogue reception is very poor, not watchable.

Are Channels 5 TDT-SD and 50 ONE HD transmitted from Moreys Hill or are these very week signals from somewhere else?

I did read "Get the Best Reception, Regional Tas" prior to posting  however the fringe area links from V4+ do not work.

There seems to be a difference of opinion as to whether the LP45F is suitable for this area as the signal from Moreys Hill is vertically polarised. Looking at the Laceys catalogue I cannot find a LP45F, only a LP45HV and LP45N. Both of these can be mounted either horizontal or vertical. However they only seem to cover channels 28 to 69 whilst I need 2 to 88?

Similarly I can see a PU4A not a PU4AF. Does this only relate to the F connector? However once again it only seem to cover channels 28 to 69 whilst I need 2 to 88?

Edited by svh60, 03 January 2010 - 11:06 AM.

[chriswoo]

Quote

Similarly I can see a PU4A not a PU4AF. Does this only relate to the F connector? However once again it only seem to cover channels 28 to 69 whilst I need 2 to 88?

Ah...i think we have a small mis-undertanding here, the numbers you are seeing on your tv (8 for win and 5 for TDT) are Logical channel numbers not the actual channels that the translator at Moreys Hill transmits on.

The channels are transmitted on the following UHF TV channels, SBS: 37, ABC: 36, WIN: 43, TDT: 39, SCTV: 47.

This will mean for best results you will need a band 5 antenna.

Quote

The only way to determine the correct antenna is usually by a site test with a number of antennas to determine the most suitable one, particularly when there are trees between you and a low powered transmitter site. Positioning the antenna is the most important parameter, in some cases this can be other than on the roof of the property. This testing will also indicate if a masthead amplifier is required.

I remember seeing antenna's at Orford, and Triabunna mounted on tree's, fences and watertanks....

Have Fun..  

[Alista]

Your Pic doesn't work. Go to the attachment forum and make a new topic ans post it there.
If analog is not good it tends to indicate a problem with the system.
The Laceys Tv catalogue is a bit out of date, the LP45HV is the older model with the direct coax connection which is no longer made. The LP45F is the newer model with the F connector.
Everything is transmitting from Moreys Hill.

The numbers you mentioned are the Locigal Channel Numbers (LCN) of each network. These are not the channels/frequency's the networks are transmitting on.

The channels for Moreys Hill Verical polarisation 150 watts directional EDIT: Chriswoo beat me to it
SCTV ch 47
TDT ch 39
WIN ch 43
ABC ch 36
SBS ch 37

You need an Australian band 5 antenna. Australian is important because many antennas are from overseas, such as Fracarro and the bands are different that's why the LP45 was mentioned instead of the LP5.

Alista

Edited by Alista, 03 January 2010 - 11:30 AM.

[svh60]

http://www.dtvforum....pe=post&id=8611

Posted photo in attachment forum and then used insert image feature so hope this works.

[M'bozo]

Can't tell what band that antenna works on from the picture, except that it is certainly UHF.

Have you ever had good analogue reception?

If you have, and it isn't now, something might be broken, from the new TV, to the flylead, and so on up the chain.

If your analogue has been poor previously, then something is wrong with your existing set-up, as mentioned before, antenna type, position of antenna etc.

A quick check shows you are around 7K from a 250 watt transmitter. Must be some blockage if the signals aren't making the trip.

What type of digital televsion do you have?

[Alista]

M'bozo, on Jan 3 2010, 02:02 PM, said:

Can't tell what band that antenna works on from the picture, except that it is certainly UHF.

Have you ever had good analogue reception?

If you have, and it isn't now, something might be broken, from the new TV, to the flylead, and so on up the chain.

If your analogue has been poor previously, then something is wrong with your existing set-up, as mentioned before, antenna type, position of antenna etc.

A quick check shows you are around 7K from a 250 watt transmitter. Must be some blockage if the signals aren't making the trip.

The antenna looks like it's quite new also.

ACMA records state that Digital is 150 watts on all channels and 600 on analog. So there must be a problem if analog isn't working either.

Edited by Alista, 03 January 2010 - 01:23 PM.

[svh60]

Am one house back from the beachfront. The two storey beachfront house in front, as well as several trees block what would be otherwise a view of the transmitter.

Have never had really good analogue signal. When I purchased a set top box for my previous TV it was great to at last get a picture that was clear. Now have a JVC LCD.

Have checked the antenna and fly lead for continuity and that is okay

Because reception on channels 2 to 34 is good (unless it is windy and or raining) yet reception on channels 60 to 80 is poor could this point to the antenna being at fault. However this doesn't explain why 5 TDT-SD and 50 ONE HD are not being received.

[Alista]

Might be good to check with others nearby and see what they say.
You might need to take the outlet off the wall and check the connections. Ideally they should be F connectors.
Check antenna Balin for corrosion and make sure everything is in good condition. Might be good to spray the connection with some clear spray varnish (Chickenfeed stuff will do) so no corrosion occurs.
How old is the antenna? It looks like it's fairly new. I would have thought it would give a satisfactory analog signal.
How many points are there in the house? if there is more than one check the splitter in the roof for problems.

Good Luck
Alista

Edited by Alista, 03 January 2010 - 02:08 PM.

[M'bozo]

Alista, on Jan 3 2010, 02:21 PM, said:

ACMA records state that Digital is 150 watts on all channels and 600 on analog. So there must be a problem if analog isn't working either.

Moreys Hill shows ~250W digital, ~1000 W for analogue when I interrogate ACMA

svh60, on Jan 3 2010, 02:47 PM, said:

Because reception on channels 2 to 34 is good (unless it is windy and or raining) yet reception on channels 60 to 80 is poor could this point to the antenna being at fault. However this doesn't explain why 5 TDT-SD and 50 ONE HD are not being received.

Is the TV connected direct to the flylead, or does it go through another item of equipment, such as a VCR, that may be interfering with the TDT signal?

You could try manual tune of the channels already given here, and see what happens. I have no experience with JVC digital TVs, so am unable to give an opinion about their performance ability.


Cluttered environments can be responsible for selective attenuation (ie loss of or reduced performance on one or more channels), which can be accentuated by wind & rain. Vertical polarisation may also be a factor, owing to non-wanted reflections from plane surfaces.

Failing equipment failure, it is all about position and type of antenna. Blockage of the signal does not help. Expert assistance may be required.

[Alista]

M'bozo, on Jan 3 2010, 04:08 PM, said:

Moreys Hill shows ~250W digital, ~1000 W for analogue when I interrogate ACMA

Well according to the stations PDF book and the Excel Data it's 150 Watt for digital. Oh well

[M'bozo]

Alista, on Jan 3 2010, 04:33 PM, said:

Well according to the stations PDF book and the Excel Data it's 150 Watt for digital. Oh well

No worries.  

I won't be too pedantic about it, as others have pointed out around here, ACMA data can be incorrect.

I'm always amused when the EIRP is specified to within a  picowatt!

[Alista]

M'bozo, on Jan 3 2010, 04:49 PM, said:

No worries.  

I won't be too pedantic about it, as others have pointed out around here, ACMA data can be incorrect.

I'm always amused when the EIRP is specified to within a  picowatt!

Yeah a picowatt wouldn't make any difference!    I wonder how they get that figure? Also is EIRP and different to ERP? Like is said the Excel and PDF book are all in ERP and the register site was EIRP???? Oh well doesn't matter.

Anyway it doesn't sound like we've found a solution to SVH's problem...

[svh60]

Thanks everyone for the responses, it is very much appreciated.

The antenna flylead goes directly from the wall outlet to the TV and there is only one outlet and one TV.

I have checked the connection at both the antenna and the wall plate and they are both okay. What I did find however is that the antenna needed to be realigned slightly.

Channels 5 and 50 are now present but pixelated. Not much wind at the moment so cannot tell if the other channels will suffer from signal degredation when it is windy or wet but I rather suspect that they will.

Don't know of any local antenna technician here but if I ask around I am sure that someone will know.

Does anyone know if the PU4AF is stocked by anyone in Hobart. I may just buy one and give it a try.

Once again many thanks.

[Alista]

Active Electronics Components should have it.
Give them a call first to see if they have it, if they don't they should be able to point you in the right direction or recommend other brands such as Hills.
Contact details HERE

[CWulf]

Alista, on Jan 3 2010, 05:54 PM, said:

Yeah a picowatt wouldn't make any difference!    I wonder how they get that figure? Also is EIRP and different to ERP? Like is said the Excel and PDF book are all in ERP and the register site was EIRP???? Oh well doesn't matter.

Anyway it doesn't sound like we've found a solution to SVH's problem...

Hi

Google ERP and EIRP and you will see that they are different!  Television and radio services are normally specified in ERPs while other radcom services are specified in EIRP. The ACMA broadcast docs will use ERP but the ACMA online interface for all radcoms services defaults to EIRP.

Obviously the online tool doesn't round the EIRP when converted from ERP. Presumably rounding could be a problem when some services may be licensed to fractions of a Watt.

[M'bozo]

svh60, on Jan 3 2010, 06:05 PM, said:

.... PU4AF .... I may just buy one and give it a try.

If you do, ensure you also get item PVP to mount the antenna in the vertical plane. Don't be overly surprised, however, if it does not fix things when mounted on the same pole as your existing antenna.

CWulf, on Jan 3 2010, 07:06 PM, said:

Television and radio services are normally specified in ERPs while other radcom services are specified in EIRP. The ACMA broadcast docs will use ERP but the ACMA online interface for all radcoms services defaults to EIRP.

Obviously the online tool doesn't round the EIRP when converted from ERP. Presumably rounding could be a problem when some services may be licensed to fractions of a Watt.

Thanks.  

I didn't know that.

[HillsTas]

SVH60, can I suggest you look at a Phased Array UHF antenna as you mention trees in the LOS of the transmitter, I stay at a shack which, going by your description, is about three houses down and have installed a UMX36 Phased Array which works perfectly. I previously tried a UHF Yagi which was OK but dropped out in the wind, and the LP345 that was there when I first stayed there was similar to the UHF Yagi. Have a look around that area, the most predominant antenna is some type of Phased Array(a square or rectangle grid). I do not use any type of amplifier. The only time I have seen the signal fail was New Years Eve, in the middle of the electrical storm, but that is to be expected with that sort of static in the air.

The UMX36 is also availabe from Active Hobart.

Cheers

Dave

Edited by HillsTas, 04 January 2010 - 08:16 AM.

[M'bozo]

svh60, on Jan 3 2010, 06:05 PM, said:

Don't know of any local antenna technician here but if I ask around I am sure that someone will know.

Looks like you have just found one.

[HillsTas]

M'bozo, on Jan 6 2010, 03:17 AM, said:

Looks like you have just found one.

Except I am not an installer, I am a salesman who used to install, its now supposedly "a conflict of interest', go figure??!?!?!!

[M'bozo]

HillsTas, on Jan 6 2010, 08:20 AM, said:

Except I am not an installer, I am a salesman who used to install, its now supposedly "a conflict of interest', go figure??!?!?!!

I think I can.

You might take work away from installers?

So, I shouldn't, by my logic, be telling people where to buy antennas - I might be giving biased advice?  

[HillsTas]

M'bozo, on Jan 6 2010, 08:29 AM, said:

I think I can.

You might take work away from installers?

So, I shouldn't, by my logic, be telling people where to buy antennas - I might be giving biased advice?  

You are probably right, but I dont mind