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xgriff
05-01-2008, 21:52
We had V+ installed in the sitting room and asked for our old box to be installed in the bedroom.

Ever since then, I've not been able to pick up 106.2FM (Heart) - it's like there's a force field around the house, because as soon as we drive away, the signal comes back!

I've also noticed today that out of the 5 or so main frequencies that Crystal Palace broadcast Freeview on, I get about 85-90% quality on 4 out of 5, but the one channel carrying BBC1, BBC2 etc is practically zero, and no amount of aerial manipulation increases it.

The latter problem is quite strange, as if the frequency is being blocked!

I'm in the Fleet, North Hants area.

Jonnymeg
06-01-2008, 13:55
I think this is just coincidence or paranoia.

Turn off the V+ and other virgin box at the mains and see it that resolves it.
I would be suprised if it did.

Octal
06-01-2008, 15:19
One quick and dirty way of checking if it's anything within your premisses is if the radio is on batteries just knock the main electrical supply switch off, if Heart re-appears then start doing a bit of detective work on tracking it down.

Stuart
06-01-2008, 15:49
We had V+ installed in the sitting room and asked for our old box to be installed in the bedroom.

Ever since then, I've not been able to pick up 106.2FM (Heart) - it's like there's a force field around the house, because as soon as we drive away, the signal comes back!

I've also noticed today that out of the 5 or so main frequencies that Crystal Palace broadcast Freeview on, I get about 85-90% quality on 4 out of 5, but the one channel carrying BBC1, BBC2 etc is practically zero, and no amount of aerial manipulation increases it.

The latter problem is quite strange, as if the frequency is being blocked!

I'm in the Fleet, North Hants area.

I suspect it's a coincidence. Theres nothing in the v+ that could transmit a signal powerful enough to block Crystal Palace.

Graham M
06-01-2008, 15:51
Tin-Foil helmet anyone? :)

xgriff
06-01-2008, 23:01
All very funny replies. Thanks!

I tried switching off what I thought was the problem, and hey presto, I got Heart back!

Whilst I had the power off upstairs, I tried adding channels again to Freeview, but unfortunately this didn't add the BBC channels that I'd hoped it would.

So it leaves me with the question : why does having the old Samsung NTL box on upstairs knock out one frequency? It doesn't happen with anything immediately either side of 106, ie 105.4 or 106.6. Tin hats out indeed.

Octal
06-01-2008, 23:11
It couldn't be one of two things, it could be a spurious emission because of a fault, or it could be the local oscillator sitting on that frequency. I don't know the frequencies or I.F's to calculate if it is an oscillator.

Losttheplot
06-01-2008, 23:20
I suspect it's a coincidence. Theres nothing in the v+ that could transmit a signal powerful enough to block Crystal Palace.

Locally there is. Does the V+ box not contain a modulator for the RF channel out of the box? I'd guess this frequency is currently set the same as Mux 1 from CP.

Octal
06-01-2008, 23:24
Interesting, I was just reading this article from last year about Freeview set top boxes causing interference.

http://www.mf2fm.com/blog/index.php?m=02&y=06&category=3

Just scroll down to the second article.

spiderplant
06-01-2008, 23:25
OK, let's take this from the top... I have lots of questions for you.

You have a Samsung box and when on it stops you tuning to 106.2FM? Is that correct?
Do you get the problem if the STB is on but the TV is off?
Which model Samsung box is it?
How EXACTLY is the Samsung connected to the TV etc? Is there any other equipment connected, such as VCR or aerial? A diagram may help.
Does the Samsung have an RF bypass (grey plastic box about 2" square) on the back?
What happens on the radio when you tune to 106.2?
What kind of radio are you using, and where is it?
How far from the house do you have to go to get 106.2 back?
What RF channel is the Samsung output set to? (Look in Settings->Technical Stuff)


Incidentally, can't you point your aerial at Hannington? It's a lot closer to you than Crystal Palace.

xgriff
06-01-2008, 23:45
Thank you Octal and Spiderplant.

I have read the article linked to, and guess that the power of the disruption is 'minimal' as the signal from Heart FM gets stronger than my radiation when I'm about 40-50feet from the house. None of my neighbours has complained though I'd peg most of them as Radio 4 listeners anyway!

I shall certainly attempt to respond to all the questions at the earliest tomorrow night and hope that I can provide some more info to help sort this. The problem isn't a train smash as I've been and bought a DAB radio - and I'm only using Freeview on occasions to watch complementary channels that V+ dont' provide but it appears there may be something more sinister that needs sorting.

---------- Post added at 22:45 ---------- Previous post was at 22:42 ----------

Sorry, Losttheplot - your explanation seems the most logical, but I'm not sure where I stand if I turn the STB off upstairs and I still can't get CP MUX1 to show anything more than 5%.

I will have a look at turning to Hannington (will need to check if that's Guildford or elsewhere and get my compass out!)

Losttheplot
07-01-2008, 10:09
Sorry, Losttheplot - your explanation seems the most logical, but I'm not sure where I stand if I turn the STB off upstairs and I still can't get CP MUX1 to show anything more than 5%.

I will have a look at turning to Hannington (will need to check if that's Guildford or elsewhere and get my compass out!)

Is the loss of freeview also only in the bedroom? I'd thought you meant it was on the TV that the V+ box was connected to. If it is in the bedroom then how does the terrestrial feed get into the TV/Freeview box? Is it a house wide RF distribution or a indoor aerial etc?