• New Patreon Tier and Early Access Content available. If you would like to support AVForums, we now have a new Patreon Tier which gives you access to selected news, reviews and articles before they are available to the public. Read more.

One frequency failing on loft aerial/masthead amp set up

Damian1978

Prominent Member
Hi guys,

Had a loft aerial installed in our new build property Nov 11.

All was well but last Summer when hot Frequency 58 on Winter Hill would fail and the signal levels would drop for the other frequencies.

Today has been quite warm and Frequency 58 has near enough dissapeared.

As the others are ok is this an aerial, mast head amp or PSU problem?

My neighbours have no issues

Thanks
 

Rodders53

Distinguished Member
Full details of makes/models of the items may give us more of a clue a clue... Also approx location (postcode within 100m of your home) and outlook from it to Winter Hill... (clear, trees, tidal water in valley).
 

Damian1978

Prominent Member
Hi,

I unplugged the mast head amp and it was ok this morning although the signal level was 15% lower on that mux.

Its a standard loft aerial with a 4 output masthead amplifier and Wollesly(sp?) PSU.

Two out puts are used and connected straight to a Humax HDR T2 and Humax Youview boxed in another room. Both show similar results in signal levels.

I'm on the Fylde coast, FY7 postcode area.

Pretty much open around me. There are building works still going on though but some distance from me.

I had similar problems last summer which went when the temps dropped. Not sure what is causing that.
 

Damian1978

Prominent Member
When I said I unplugged I meant I unplugged the mast head amp PSU overnight.
 

Rodders53

Distinguished Member
FY7 is the Fleetwood area... so taking Houses for sale in Fleetwood, Lancashire, FY7 6FQ - Harbour Village as an example postcode... give a prediction like this Coverage Checker - Detailed View

Have you ever connected the aerial to one outlet direct (i.e. no amplifier at all)? If no do give it a go - especially the next time you get problems... it may even be possible to passively split the signal to two receivers if the levels are strong enough. Assuming you do need an amplifier, though: if the 4-way amplifier has a variable gain control try it lower as well as higher when you next have problems... too much signal can be as bad as too little. Ideally any unused outlets should have a 75-ohm termination on them. Therefore it is a good idea to go over all the connections and plugs/socket with a fine tooth comb to ensure there are no dodgy joints, crushed or damaged cables and loose joints.

You are likely to have a Wolsey amplifier as well as the power unit... It is possible that the amplifier is over-heating or the power supply brick also, either of which could add noise and other 'nasties' that upset the signal - but both would need opening up to see if they had problem with the internal component, or use the substitution method to eliminate them (i.e. another psu and/or amplifier). Masthead amps are usually mounted outside and, in direct sunlight, will get hotter than any loft should get, so are usually designed to cope with extremes of temperature with no issues. (The psu is a different matter, of course). Cables and connections can also expand and contract with heat and in unusual cases solid wires can fracture or the connections work loose - this can be enough to give very odd frequency dependent problems that are intermittent.

BTW, there's no such thing as a 'standard' loft aerial... have a look at Aerials, TV Aerial and Digital Aerial and see which of the ones pictured is like to one you have fitted. Loft and indoor aerial installations for TV, FM and DAB and Television Aerial Boosters / Amplifiers, Splitters, Diplexers & Triplexers also make useful reading.

It's quite possible, of course, that the aerial need relocating within the loft space to equalise the signal levels: higher/lower, crabbed left/right and nearer/further from the transmitter while maintaining the same pointing direction... the problem is that then the issue may change to affect one of the other frequencies. (A good aerial installer would use a meter - or better a spectrum analyser display - to ensure all the frequencies are received equally strongly).
 

Damian1978

Prominent Member
Freaky!! That link is to my actual builders on the estate we live on!!! :)

Thanks for that. It seems ok at the mo but will disconnect the PSU next time to check.

Can I just replace it with any mast head PSU? Any better makes?

Just thought if its cheap enough I'll get one in then if it happens again I'll get the aerial installers out.
 

Damian1978

Prominent Member
Doh. Its doing it again but not as bad. Signal quality on that mux is way down but giving a picture.

All other muxes are normal.
 

Damian1978

Prominent Member
Actually my TV reports the quality lower on that mux for some reason.

On the Humax HDR T2 its 54% strength, 100% quality.

Most of the others are 68% to 74%
 

Damian1978

Prominent Member
Ok.

Doing it badly now so removed the amp. No signal at all. Put amp back on and its not quite as bad.

The aerial faceplates we have fitted are a bit naff and not shielded so ordered 2 Labgear non isolated shielded ones for £9 all in and that PSU just in case
 

The latest video from AVForums

Spielberg, Shyamalan, Aronofsky, Chazelle, Eddie Murphy and Mel Gibson - all the latest movies
Subscribe to our YouTube channel

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom