Fitting an DTT Aerial?

The Bull

I have a general question about fitting a UHF aerial. I have fitted satellite dishs plenty of times before and fancy having a go at fitting an aerial in a new house. I have a 2 cables running from each of the bedrooms and the main sitting room to one point in the attic. One of the cables is to be left for distributing satellite to each room and the other is left for DTT. I plan to fit a masthead amp similar to the one available below outside near the aerial.
http://cgi.ebay.ie/1-Way-Aerial-Masthead-amp-outdoor-booster-amplifier-/350464013263?pt=UK_ConEle_SatCableFreeview_RL&hash=item51994873cf#ht_1547wt_754

The question I have is in relation to the power supply. Cause I am sending the signal to multiple rooms could I use a something like this

http://cgi.ebay.ie/A280L-PRO-ANTIFERENCE-8-WAY-PROFESSIONAL-TV-AMPLIFIER-/230654819211?pt=UK_ConEle_SatCableFreeview_RL&hash=item35b4193b8b#ht_729wt_932

instead of the power supply shown in my first link or would it be better to use the single input power supply and then run the cable into some sort of other 8 way splitter?

Is this a round about way of doing this or would any of you recommend another more efficient option.

Thanks in advance

Peter Rhea

The line-power on the Antiference distribution amp. is fine for powering the masthead, I have one myself.

The Bull

Peter Rhea wrote: »

The line-power on the Antiference distribution amp. is fine for powering the masthead, I have one myself.

Would this do the same job as well ?

http://cgi.ebay.ie/8-WAY-aerial-signal-amplifier-freeview-booster-TV-SLx-/370525207914?pt=UK_ConEle_SatCableFreeview_RL&hash=item564505fd6a#ht_2369wt_754

Peter Rhea

It will, but I'd prefer one with f-connectors, specially for passing power.

The Cush

The Bull wrote: »

Is this a round about way of doing this or would any of you recommend another more efficient option.

Thanks in advance

Where are you located, how is the DTT reception at your location?

Do you really require a masthead amp?

I'd avoid using 2 amps on the one feed - http://www.megalithia.com/elect/boostercasc/index.html#lowsens.


My suggestions

- aerial feed to distribution amp in the attic, distribution amp output to each room
or
- masthead amp feeding power supply in the attic and output to passive TV splitter 2-8 outputs as required


Did the latter for my brother last year, with a standard contract aerial in a medium signal strength area feeding 6 TV points. Perfect DTT and v. good analogue.

The easiest would be the first suggestion with a standard distribution amp in the attic.

The Bull

The Cush wrote: »

Where are you located, how is the DTT reception at your location?

Do you really require a masthead amp?

I'd avoid using 2 amps on the one feed - http://www.megalithia.com/elect/boostercasc/index.html#lowsens.


My suggestions

- aerial feed to distribution amp in the attic, distribution amp output to each room
or
- masthead amp feeding power supply in the attic and output to passive TV splitter 2-8 outputs as required


Did the latter for my brother last year, with a standard contract aerial in a medium signal strength area feeding 6 TV points. Perfect DTT and v. good analogue.

The easiest would be the first suggestion with a standard distribution amp in the attic.

Am i right in saying that a masthead amp is optional and if i use a normal aerial and run the cable directly to a distribution amp it works as well.
In your brothers house did you use a standard power supply and then the passive tv splitter

By the way i am a few miles outside westport and about 10 - 15 miles or so from the nearest DTT transmitter

The Cush

The Bull wrote: »

Am i right in saying that a masthead amp is optional and if i use a normal aerial and run the cable directly to a distribution amp it works as well.
In your brothers house did you use a standard power supply and then the passive tv splitter

By the way i am a few miles outside westport and about 10 - 15 miles or so from the nearest DTT transmitter

If you're 10-15 miles from the nearest DTT transmitter you should have no problem with an external aerial feeding a distribution amp.

My brother's setup - Aerial -> Masthead Amp -> Power Supply -> Passive Splitter.

Peter Rhea

The Bull wrote: »

. . . a standard power supply and then the passive tv splitter

You can have the power supply after the splitter, as long as the dc power is passed to the input cable & so on to the amplifier.

Also, there's no way any of us here can know how strong the signal is at your location based only on distance from the transmitter, and not taking into account which transmitter it is & the terrain etc.

Mexecutioner

The Bull wrote: »

Am i right in saying that a masthead amp is optional and if i use a normal aerial and run the cable directly to a distribution amp it works as well.

If your signal level is any way marginal, first make sure you have a decent aerial then consider the use of a masthead amp. If you don't have proper measuring equipment, run a single cable direct to 1 tv & maybe use attenuators to see how much signal can be lost before it becomes unacceptably low.

What you put after the mast amp depends on its rating, how many tv points you wish to feed, cable lengths etc. A low to medium gain masthead, say < 16dB should feed a decent distribution amp without any problems, assuming the received signal level was low enough to require amplification in the 1st place.

winston_1

Of course with a decent aerial you may not need any amplification at all. Just a passive splitter.

The Bull

Thanks for the help guys, i gone ahead and bought a UHF aerial and mast headamp from tvtrade. I have also got a power supply and an 8 way passive splitter to send it to the various rooms. I intend to have a similar setup to
The Cush's brother's setup - Aerial -> Masthead Amp -> Power Supply -> Passive Splitter.

TeachMealog

would say fitting the UHF aerial is easier than a Sat Dish!
Also look at the option of joining the sat signal and aerial using splitter/combiners so as you can use the 2nd cable for Freesat+/Sky+
For 15km masthead should not be needed with a good line of sight and aerial. pointed correctly and with correct polarity

http://www.mpeg4ireland.com/aerial-setup

cast_iron

TeachMealog wrote: »

For 15km masthead should not be needed with a good line of sight and aerial. pointed correctly and with correct polarity

Being so close to the transmitter, it may well lead to overload of the signal if you use the amp. If so, yo will have to leave the amp out.

Peter Rhea

OP should have assessed the signal quality at his location before deciding on the configuration of his distribution system, people shouldn't speculate on what's needed based solely on his distance from an unknown transmitter (probably Castlebar).

hesker

So how would you go about doing that. I'm looking to buy an outdoor aerial for a location which is 42km south of Mullaghanish and 9km west of Clonakilty. It's also in a bit of a valley so not clear if there is line of sight to either.

Current analogue reception on an indoor aerial is poor for TG4 and non-existant for TV3.

Saorview coverage map suggests Chan 21 for DTT from Mullaghanish. So I could buy a Group A high gain aerial.

Coverage map on mpeg4ireland suggests Clonakilty Infill transmitter and a group C/D aerial.

Or I could get a wideband aerial, which may work or may require signal boost

Can I narrow the decision down any better than that?

Peter Rhea

Well, RTE's map certainly favours Mullaghanish for locations in that area & a grouped aerial is definitely to be recommended for group A transmissions.

Wideband Yagis (the typical tv aerial) are poor in the lower frequency range, log-periodics & grids have lower overall gain.

Vince Cable

hesker wrote: »

So how would you go about doing that?

One of the benefits of getting an installer in, is that they can try different setups without you having to buy everything.

Although some of us non-installers here don't mind buying a variety of stuff & tinkering, others' approach will (sensibly) favour economic factors.

The Cush

hesker wrote: »

So how would you go about doing that. I'm looking to buy an outdoor aerial for a location which is 42km south of Mullaghanish and 9km west of Clonakilty. It's also in a bit of a valley so not clear if there is line of sight to either.

Current analogue reception on an indoor aerial is poor for TG4 and non-existant for TV3.

Saorview coverage map suggests Chan 21 for DTT from Mullaghanish. So I could buy a Group A high gain aerial.

Coverage map on mpeg4ireland suggests Clonakilty Infill transmitter and a group C/D aerial.

Or I could get a wideband aerial, which may work or may require signal boost

Can I narrow the decision down any better than that?

You don't need line of sight for terrestrial TV but a hill in front of the transmitter wouldn't be good either.

What type of aerial are you using at the moment for analogue TV reception? No analogue TV3 could indicate Clonakilty transmitter or VHF aerial pointing at Mullaghanish. Can you identify the frequency/UHF channel numbers of the channels you currently receive?

The mpeg4ireland coverage map was a good resource before RTÉNL's own Saorview coverage map became available but even then they do say the coverage is indicative only and subject to the local environment - trees, hills etc.

Since last year Mullaghanish has a new taller mast which will extend DTT into areas where the analogue signal could not reach. Anyone in the area with an aerial pointing at Mullaghanish?

I'm over 90Km NE of Mullaghanish and use one of these http://cpcireland.farnell.com/blake-uk/dmx10a/dmx10-high-gain-uhf-aerial-group/dp/AP01123 with no clear line of sight.

hesker

Thanks for replies..

It's a house share and I won't be back there for a while so I can't find out anything about channels or where the neighbours aerials are pointing.

I'll have a look next time I'm back there. I'm tempted to get the Group A and point it to Mullinghanish.

Here is a rough elevation profile from Google Earth with
Mullaghanish on the far left and the proposed aerial location on the far right. I expect this has limited value but you can see proximity of neaby hills.