TV signal strength

[davecooper]

After losing three roof aerials to either the weather or seagulls, I have been using a loft aerial and booster for a number of years. I always had some reception problems with all the roof aerials and no better with the loft aerial, but at least it is safe from harm. I now want to try a roof aerial again and along with it, look carefully at every link in the chain, ie: cable and connector quality and cable routing etc. However, the choice of aerial is the problem at the moment, not because I haven't got some in mind but because I don't know how good a reception area I am in. The freeview map will tell you your transmitter, what group it is and the area covered but nowhere can I find out whether I am in a strong, medium or poor reception area as this would help in choosing a aerial.
Looking up signal strength at my address just brings up how to see it on my TV. That's no good because I am using a loft aerial in a far from ideal location which is showing anything between 40% and 60% signal strength and around 60% signal quality. However, that doesn't really tell me what the true signal strength is in my area. I am in Ulverston, south Cumbria which uses the Winter Hill transmitter near Bolton. It is a group A transmitter at a distance of around 70 miles.
Any advice welcome. Thanks.

 

[Rodders53]

As I have stated over on AVForums a nearby postcode, within 100m of yours (we don't want to identify your exact home in an open forum) is needed to give better accuracy.

Ulverston Post Office postcode is 46 miles, 74 km from WRH and at that prediction 100m x 100m square, Lancaster is an alternative transmitter to use (slightly worse for interference but still all green).

Wolfbane signal strength prediction is Lancaster is significantly stronger (10dB) but it is inaccurate for WRH as it uses the old C/D frequencies which travel less well.

TV meters: Signal quality is more important than strength usually.

A professional aerial installer should use a test aerial and (expensive) signal meter to determine what is required at any specific location.

 

[Lucid]

Look up "Wolfbane signal prediction".

 

[davecooper]

Thanks very much. Have been trying to remember the Wolfbane site. I think that will be a great help. What it suggests is that reception at my address from Winter Hill is not great. I have had a walk around the area and it appears that there are a number of aerials with masthead amps which should tell me something.

 

[Rodders53]

Remember if your WRH antenna is C/D (as was correct in analogue and early DTT/DSO years) it may be pretty poor gain at the new group A frequencies WRH moved to with the 700 MHz clearance.

Some masthead boxes contain low gain distribution amps. Some will have been installed for the early DTT signal levels (in the presence of analogue).

Group A travel better/further than group C/D frequencies so as power is the same signals should be a little higher than Wolfbane suggests I think?

Wolfbane at the PO in Ulverston postcode gave, for WRH, 39dBuV/m at 10 agl outside. Clear line of sight.

It also gave 49 dBuV/m for Lancaster. If the Local Preston TV mux (ch 40) is unimportant, simply cant the aerial in the loft over to Vertical polarisation and point to 120 degrees rather than 150 degrees (ESE rather than SE). Retune and re-measure the signal levels/quality. If no better then revert to WRH.

 

[Lucid]

Thanks very much. Have been trying to remember the Wolfbane site. I think that will be a great help. What it suggests is that reception at my address from Winter Hill is not great. I have had a walk around the area and it appears that there are a number of aerials with masthead amps which should tell me something.

Wolfbane doesn't always get it right. As @Rodders53 says, it's also out of date WRT the RF channel numbers. I'm on Winter Hill too. My place is a little over 30 miles due south. Wolfbane tells me I need an amplified extra high-gain aerial. I'm running exactly the opposite; a low gain Log Periodic without an amp. I also pick up the Manchester and Liverpool local muxes and I can get ITV from Emley Moor over in Yorkshire.

The Freeview site has the reception predictor for professionals: https://www.freeview.co.uk/corporate/detailed-transmitter-information When I put my house details in then this gives a closer match to what I'm receiving.