Tv aerial problem

[Terry7556]

At a customers house where we carried out a Powerflush the tv system was working on the day, now it is not . Signal breaking up etc. although another odd thing is of the boiler is turned off at the fused spur the tv screen goes blank saying weak signal
The loft is long, 70-80 feet, it's a big bungalow
In the loft is one aerial and that box , Taylor ts 2004 that feeds 5 aerials
I have had a look and with limited knowledge I can't see anything obvious
Any pointers please?
Is that box old and past it with a possible electrical fault in the house?
Replace the system with individual aerials and modern aerial cable instead of the old brown cable? View media item 66438 View media item 66439

 

[plugwash]

although another odd thing is of the boiler is turned off at the fused spur the tv screen goes blank saying weak signal

That does seem odd, it would appear to indicate that the aerial amplifier was powered off the central heating system but why would someone do that?!

What exactly is involved in a powerflush? where is the powerflush equipment powered from? how is it connected to the heating system? were any workmen working near the aerial who might have dislodged it?

 

[Lucid]

The powerflush is a one-time operation to clear the heating system of sludge and deposits that build up over time and cause a reduction in the efficiency of the heating system. It's a liquid chemical additive actively pumped around the heating system then drained. Hence Power and Flush.

The cause of the problem is that the aerial amp is powered from the boiler circuit. It's now considered bad electrical practise to have a 240V AC device like this running in the loft unattended.

From the look of the picture it seems like there aren't enough signal outlets for the TVs in the house anyway. Also, there are amps now available that use something called phantom power. This means that the 240V-to-12V DC power supply can be located behind on of the house TV and it can send power up one of the aerial cables that's used for signal down to the TV. That means no rewiring, no loss of performance and a much safer install going forward.

A Labgear MSA283LP/S is a widely available modern and safer alternative to the old Taylor unit. Screwfix have it for £35. In the trade we have moved away from using RF aerial plugs. We now use those screw type satellite plug (F connectors). So changing the aerial distribution amp means fitting different plug ends on the wires. It's all pretty straight forward though.

 

[Terry7556]

Plug wash hi
The pump is removed and in its place we make a connection from heating corcuit to pwerflushachine .turn off all rads ( in this case 13, said it was a big bungalow),open one rad and pump/ flush it clean. Close rad open next one , repeat for all rads,mundane really
A few days before we added chemicals to the heating system to break down what was in there

 

[Terry7556]

Hi lucid cheers for the info. Looked at the Screwfix catalogue and I think you are saying go for it item number 23283, on page 365 which also has the 240-12v transformer with it
Could you please identify which f connector I need as there are 6/7 with f in the description, it's page 368 in the current catalogue
Many thanks again terry

 

[Lucid]

Hi Terry, My catalogue is out of date. I tend to use the web more. The product description is Philex Coaxial F-Plug Pack of 10 - £1.95 (1-4), £1.85 (5+)
Product Code: 17061

You're right with the Labgear amp as product code 23283


To complete the job you might need a short length of coax. This is for the power supply that lives behind one of the TVs. The power supply goes in-line on the aerial cable fly lead from the wall to the TV. Most times you can just cut the cable somewhere convenient along its length, then fit the F connectors and hook up the power supply. Very occasionally you'll find that the fly lead is a bit short or they've got one of those awful premade crappy coax cables with the moulded plugs. They're neither use nor ornament. They're too thin for the F plugs to fit. If you are onsite again before sorting out the aerial amp you'll have the opportunity to check it out first. If you do have to buy some cable then get satellite coax. Though I hate to point you towards them, but Maplin sell it by the metre at £1.99 in black (XS16S) and white (XS17T). Anywhere else retail it's either crap quality or sold in bulk which is a bit OTT for this job.

That should sort your little job out perfectly.

 

[ericmark]

Warning some aerial plates have capacitors fitted to stop atmospheric voltage from being present at the socket clearly not required with inside aerial but often still there. These will stop DC current and will stop the DC feed reaching the amplifier. I have in the past had to bridge these capacitors in my case to get digi-eye to work but same applies to pre-amp feed.