TV Signal Strength Meters

Owain_Moneysaver

They're useless.

More important than signal strength for digital TV is signal quality. This is why professional installers use signal analysers not meters.

Most digital TVs/set top boxes have a signal strength/quality meter in their setup menus anyway.

You can use the reception predictor at Wolfbane which will give you the compass bearing from your location to the transmitter.

Mistral001

Just an update. The TV aerial stopped working altogether and new aerial will not arrive in the post until Tuesday at earliest. I could not wait until the new aerial arrived so I adapted an indoor set top aerial off a old portable TV I had and tried it in the loft. I used said portable TV and Freeview box in the loft to adjust the position of the aerial. Believe it or not it worked fine. The only problem I have is that I have a £30 aerial arriving in the post that I do not need.

I am now converted to loft aerials. Not many people use them in my area for some reason, but they seem to a very good idea as the outdoor aerials seem to need a lot of costly maintenance.

Mistral001

Further update. TV aerial arrived yesterday and I erected it in the loft with aid of small portable TV as "signal meter".

It is only marginally better than the homemade one and takes up more space.

BTW the aerial I bought comes with a massive "reflector" at the back of it (looked impressive in picture on ebay!). I took this off to keep the aerial above head height and replaced it with a single steel rod I found in my garage. Doing this did not adversely affect the reception, in fact it improved it if anything as I could install the aerial 18 inches higher.

So saved myself £10 on not buying a signal meter. So thanks everybody who advised that they would not be any good.

A tip that I could pass on is to not ignore the possibility of fitting the aerial in the loft. Apart from the cost saving which is massive, they keep them away from the weather and corroding connections etc. Also, large reflectors may look good, but seem to be a waste of money.

Ainsley1

A technical note:
Mistral if your signal is good, what the heck, who cares about theory! However you might find that you are getting adequate reception at present but not if weather is bad (heavy rain), atmospheric condition are not good (sunspot activity), local interference increases, any trees in the way come into leaf or the transmitter is on low power. If so the following may be of use to you. Minor tweaks can have a big effect!!

Reflectors do a useful job when you have reflections/interference especially from the rear. The whole design relies upon all the elements so generally best not to take it off!
The 18" higher improved performance is probably more to do with avoiding nulls in the signal and finding the peaks: A poor analogy is a photograph of waves on the beach (i.e. static in position) and the peaks of the waves are in specific positions. The same applies to these terrestrial radio waves for TV.

Antenna in the wavelength band involved are therefore very positional sensitive, not only to height but also lateral and fore/aft position and rotation in all 3 planes.

The waves do not travel horizontally (or direct line of sight from the transmitter) near to ground level but tend to 'dive down' so moving the antenna forwards or backwards has a significant effect as does tilting up the forward end just a few degrees. The general rule of higher the better does not apply over a few inches -wave peaks being more important) but does over a few meters (sorry mixed measures!!), all other things being equal.

spacey2012

Cut the coax plug off neat, go online and look up how to fit a new one.
If the plug has just one strand out of place the signal will be lost.

Ratboy

As I understand it, from a person that used to make aerials; the reflector part is the most important part of the aerial, as this directs the received signal to the receiving end.

I fixed up a satellite dish with no beam directors, or signal finders.

I simply pointed it the same way as my neighbours were pointed. Het presto! Job done!

Mistral001

Ainsley1 wrote: »

Reflectors do a useful job when you have reflections/interference especially from the rear. The whole design relies upon all the elements so generally best not to take it off!

Yes this is something I picked up during my homemade yagi aerial design experience. The reflector is not really there for reflecting signals from the transmitter that you are aiming at, but reflecting them from unwanted tramsmitters at the rear of the antenna. The aerial I bought has massive reflectors almost like a a satelite dish suggesting that they are directing the signal from the tramsmitor towards the dipole whereas it is dealing with the unwanted signals from other transmitters. The size of it might make a difference if you have lots of nearby tranmitters in the vicinity, but that is not my situation.