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What they said about us.....



"The robust installations are a good advert. A no-nonsence approach."

Tim Jenks
Senior Executive
Confederation of Aerial Industries



"This is a company that has been built up on a solid reputation.

I am fortunate that I know Woking Aerials work, his reputation goes before him. Any person employing Woking Aerials is assured of a job well done.

Again being able to see work close up shows that Alan provides a service which is to be envied.

The system viewed by me was very impressive...."

Chris Glover
Inspector
Confederation of Aerial Industries



"This assessment was carried out as an NVQ assessment session.

I observed Alan, visit a domestic property, qualify the customer, fault find/diagnose the reception issue, and install a complete new aerial system.

This was done to an exceedingly high standard."

Kevin Dawson
Assessment & Training Executive
Confederation of Aerial Industries


Kevin is also the UK TV expert for ITV's 'House of Horrors' & BBC's 'Rogue Traders'

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Aerial Installation Report



Signal Analysis, The Results.


The figures highlighted in red are the minimum and maximum recommended published levels at the receiver.


Signal results from the new aerial installed by Woking Aerials. These measurements in Table 'A' were taken at the wall outlet in the lounge, after all cable losses.


Table 'A'

Analogue Level 60 – 80dBµV C/N >43dB
 
BBC1 72.8dBµV >51.3dB
BBC2 69.4dBµV >47.1dB
ITV 73.6dBµV >49.7dB
CH4 71.1dBµV >49.3dB
CH5 67.1dBµV >50.1dB

Digital 64 QAM Level 45 – 60dBµV C/N >26dB
 
Mux 2 57.6dBµV >32.7dB
Mux A 54.9dBµV >39.9dB

Digital 16 QAM Level 42 – 60dBµV C/N >23dB
 
Mux 1 58.2dBµV >42.5dB
Mux B 57.6dBµV >43.6dB
Mux C 53.7dBµV >40.1dB
Mux D 56.2dBµV >39.5dB

Table 'B' shows the signal results from the same position in the lounge after the attachment of the alleged ‘weak booster’. Every channel showed an increase in signal levels.


Table 'B'

Analogue Level 60 – 80dBµV
 
BBC1 87.0dBµV
BBC2 81.5dBµV
ITV 85.7dBµV
CH4 84.3dBµV
CH5 79.9dBµV

Digital 64 QAM Level 45 – 60dBµV
 
Mux 2 68.5dBµV
Mux A 65.0dBµV

Digital 16 QAM Level 42 – 60dBµV
 
Mux 1 71.1dBµV
Mux B 69.0dBµV
Mux C 63.5dBµV
Mux D 65.3dBµV


Table 'C' shows the signal levels taken from the aerial, still in situ, in the loft as installed by XXXXX Aerials, this measurement has been taken before losses for the cable run are added.

Being as the existing downlead was as old as the house, about 30 – 35 years, the cable loss would have been a minimum of 2dB, but realistically 3 – 4dB or possibly more.

This would put BBC2, CH4, CH5, Mux A & Mux C below the recommended published signal level and Muxes B & D borderline at the receiver.


Table 'C'

Analogue Level 60 – 80dBµV C/N >43dB
 
BBC1 65.9dBµV >49.7dB
BBC2 60.8dBµV >49.0dB
ITV 65.8dBµV >46.0dB
CH4 58.0dBµV >45.2dB
CH5 57.3dBµV >46.1dB

Digital 64 QAM Level 45 – 60dBµV C/N >26dB
 
Mux 2 63.5dBµV >36.5dB
Mux A 44.3dBµV >30.7dB

Digital 16 QAM Level 42 – 60dBµV C/N >23dB
 
Mux 1 51.7dBµV >38.0dB
Mux B 47.4dBµV >34.0dB
Mux C 43.2dBµV 6.7dB
Mux D 47.3dBµV >34.0dB

Signal levels taken using the 30 year old aerial for a comparison as an exercise.

Whilst any aerial installation engineer would agree that the old aerial is not suitable for stable digital reception by comparison the old aerial performed better than the new aerial on the analogue channels and it matched the new aerial 50/50 on the digital muxes, as shown in Table 'D'.


Table 'D'

Analogue Level 60 – 80dBµV C/N >43dB
 
BBC1 59.7dBµV >44.7dB
BBC2 64.0dBµV >52.3dB
ITV 63.0dBµV >44.8dB
CH4 59.2dBµV >47.2dB
CH5 59.7dBµV >48.4dB

Digital 64 QAM Level 45 – 60dBµV C/N >26dB
 
Mux 2 49.4dBµV >26.1dB
Mux A 46.1dBµV >32.0dB

Digital 16 QAM Level 42 – 60dBµV C/N >23dB
 
Mux 1 48.6dBµV >33.8dB
Mux B 46.1dBµV >34.0dB
Mux C 46.6dBµV 9.2dB
Mux D 47.4dBµV >33.2dB

Hence, how can XXXXX Aerials class the new DMX15 aerial to be an ‘upgrade’?

The moral of the story is, just because a person or company is a member of a Trade Body, it doesn't mean that you will always get an installation which complies to the Trade Body's Installation Codes.


Page 1. Installation Report. Page 2. The Wrong Advice.