Question Loft aerial recommendations

Mike RB

Active Member
Hello, I'm looking to buy an aerial to mount in the loft (we are not allowed to install on the outside of the house).

I live in the RG26 5AQ area and according to the freeview checker, I'm 13KM from the Hannington transmitter.

I was looking at the Labgear LAB450T but not sure if this is a bit over the top for my requirements. Can anyone recommend something suitable for this location please.

Also, the aerial (coax) cable goes to the cupboard under the stairs. There are also cables in this cupboard that feed the living room and bedroom TV points. At this time, I'm only interested in hooking up the living room TV so I'll need to join the cable feeding the aerial to the aerial that feeds the TV point in the living room. I'm thinking F Connectors with an F Connector coupler to join them. Please let me know if you have a better idea on how I could do this.

Many thanks
 

Rodders53

Distinguished Member
TVs require between 45 and 65 dB ref 1 microVolt (uV) terminated to work properly.

Wolfbane predicts 66 dBuV/m at 8 metres above the ground outside in the open from Hannington for the 25kW erp multiplexes. +3dB for the three PSB 50kW muxes. COM7 is 27kW so roughly the same.

Roof materials will attenuate by at least 10 dB, so =56dB.

An aerial will have gain
A Blake LP-22 from Toolstation has a useful gain of around 6 dB (9dBi sotropic) as does the equivalent small log from Labgear from Screwfix.
=62dB
The TriBoom is over large - most lofts won't have room to fit it and move around to point correctly. It does have a claimed gain of almost 14dB (16.5dBi) - but that is the 'peak gain' - see ATV aerial gain tests : all the gain curves - A.T.V. Poles, Brackets, Clamps & Aerials and a lot less at some frequencies.

Cables and terminations (each plug, socket and joiner lose a little bit) allow 3 to 4 dB loss.
=58dB

=Perfect signal level for a TV tuner.

A 2-way splitter will lose 4 dB and that's still in the middle of the ideal range.

Loft aerials - A.T.V. Poles, Brackets, Clamps & Aerials is worth a read as are other Knowledge articles.

NB Loft aerials need to point out through the roof tiles or gable end into a clear unobstructed view.
If the aerial points along a terrace and through one party wall after another... the signal attenuates very, very rapidly.

In the loft I'd consider using the Yagi 10K from ATV aerials for the extra gain in the 39-55 band it offers for Hannington over a log periodic, while still being pretty compact.

If no external antennas (aerials) are allowed how do people manage for satellite antennas (dishes)??

NB2 F-plugs and a barrel joiner is the ideal connection method. Wiring up plugs, aerials and wall plates - A.T.V. Poles, Brackets, Clamps & Aerials

NB3 screw on f-plugs come sized to the cable diameter they are used with. ($ky WF65 5mm thin shotgun vs 6.5mm WF100). Ensure you have/ buy the correct ones.
 

Mike RB

Active Member
@Rodders53

Many thanks for your reply. I really appreciate the time you took to look at this for me and the detail you have given me.

Regarding the aerial choices you have recommended me, can you confirm I am looking at any of the following (I want to make sure I've found the correct product before I purchase):

Blake LP-22 - The website says the 28 element is ideal for homes, but you're recommending the 22 element? Can I just confirm it's the 22 element that would be better suited to my situation?

Labgear Log Mast Periodic Aerial

Yaki 10K Aerial

It looks like you favor the Yaki 10K (correct me if I'm wrong) but would ideally go for one of the other two as I can go and pick them up locally so I'd be either looking at the Labgear or the Blake. Are these two much the same or would you recommend one over the other? I may have an easier time with the labgear as I understand it uses a F connector.

We are allowed Satellite dishes but must be below roof height and situated at the rear of the property. I have coax ready and waiting in the loft so would prefer to use freeview if possible.

Thanks once again.
 

winston2010

Well-known Member
The LP22 does not have 22 elements. Blake are lying. It has 22 half elements.

But anyway Rodders53 is very experienced in this and if he calculates the LP22 is OK I would trust it. The LP28 would give slightly more signal but not enough to cause overloading.
 

TJT1

Member
I cant even see 11 elements (to make the 22). I can only count ten. But I suppose they are counting the support booms as well.
I actually have one of the screwfix ones fixed to my eves and it definitely only has 10 (conventionally counted) elements = 20 half elements + two booms.
 

Rodders53

Distinguished Member
Ignore the element count on these logs it's a marketing gimmick. In any case only a few elements are ever 'active' on any particular frequency, those with the correct wavelength tuning.
The 'booms' TJT1 refers to are the transmission lines for the signals picked up by the elements on each. They are connected at the pointy end by a coax cable passed back inside one of them to the F-sockets by the mounting bracketry.


Log periodics by Blake:

DML14 has 6dB gain (ref a dipole) 595 mm long
DML18 has 7dBd gain, 745 mm
DML26 has 8.6dB gain, 1055mm.

BLA LP 22 has just under 7dB gain, ?450mm, {Toolstation 33634}
BLA LP 28 is just under 8dB gain, 1090mm ( Toolstation 31278}
BLA LP 36 is just over 10dB gain, 1300mm.

The BLA LPs are claimed to be more ruggedly made than the DML. The solid looking rods as cf bent flat plates and plastics would recommend them to me. (Although inside a loft that matters less).

The Screwfix Labgear LOG is almost identical in design and gain to the Blake 22. Outdoor TV Aerials - Labgear

Additional aerial gain is always good, even if only 1dB more. IF you have the space in the loft. As high up as possible, to clear surrounding objects between the aerial and transmitter.

In theory the small log should be fine - but in practice it's an unknown. A diligent professional installer would use an expensive calibrated meter and test aerial to determine aerial choice, which I can't do remotely.
Most just throw up the 'normal aerial for the area' based on previous installs nearby and only need to engage brain (and equipment) when that doesn't work.

Normally I'd suggest looking at other aerials on nearby houses. Streetview shows me 10 or 18 element contracts for Hannington and 18 element upwards for Crystal Palace. So I'm reasonably optimistic that a small log should work OK.

IF the rear of your house faces towards Hannington you could install these small logs outside at gutter level to get the benefit of no loss due to the roof or gable end. If that Covenant is enforceable, since a dish is an antenna is an aerial...
 

Mike RB

Active Member
Thanks once again @Rodders53.

Today I picked up the Screwfix Labgear LOG. I installed and connected the cables in the cupboard using screw on F plugs and then hooked up the aerial and left it resting on the landing banister. At this point I just wanted to tune the TV and check it was working but didn't expect a good signal or many channels. To my surprise, it picked up everything.

I've now rested it on string in the loft which I know isn't technically correct and not correctly installed and getting 100% quality and anywhere between 50% - 75% signal strength depending on the channel according to the TV.

Many thanks once again. Total cost was around £23 for the aerial and all the connectors etc.
 

Rodders53

Distinguished Member
I've now rested it on string in the loft which I know isn't technically correct and not correctly installed and
Cheek!
That's exactly how I installed the Triax 10 element yagi in my son's loft! Right up in the apex as high as possible to maximise the signal level.
What you've done is a proper job ;)

FYI When I worked doling out this advice (last century) we regularly suggested that method for loft aerial installs as string and cable ties don't cause unwanted attenuation or reflection of radio waves.
 

The latest video from AVForums

Panasonic HZ2000 OLED TV Review: The best OLED for movie viewing in 2020
Top Bottom