Receiving Freeview (UHF) from multiple transmitters

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LarzGearbox

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#105488 5-Jul-2012 08:43

I have a TiVo and the channel list reports 2 of each channel, only one of them is ticked though.

I had a look through the ticked channels and wondered if this is normal...

TVNZ channels show the frequency as 586Mhz - this seems to be from Fitzherbert, which is about 3km from my house - perfect vision (the unchecked instance of these channels shows 578 Mhz (I guess from Kaukau, much further away).

However, the other channels all seem to have defaulted to the Kaukau frequencies i.e. TV3 has 562 mhz checked and not 570mhz as I would have expected from Fitzherbert. (I think i have the numbers around the right way)

Any idea why / how the defaults work??

I also assume this would cause issues as Fitzherbert is vertically aligned and Kaukau is horizontal??? I have over 90% strength on all channels but still get a bit of break-up from time to time, i think mainly on TV3 or 4 atleast weekly (the missus glares at me like it is my fault).

Jaxson

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#651076 5-Jul-2012 08:46

LarzGearbox: the missus glares at me like it is my fault

It is your fault, you'll never convince her otherwise

Jaxson

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#651080 5-Jul-2012 08:47

Do you get two versions of all channels?
From memory you can go through and tell the TIVO to delete a channel for good. If you have each version of the channel in the lineup, just go through and delete the worst ones.

LarzGearbox

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#651084 5-Jul-2012 08:50

Jaxson: Do you get two versions of all channels?
From memory you can go through and tell the TIVO to delete a channel for good. If you have each version of the channel in the lineup, just go through and delete the worst ones.

I do get 2 versions of each channels, the TiVo has a check box that allows you to 'hide' channels, the TiVo had by default selected some channels from Fitzherbert and some from Kaukau, unsure why. I thought it would pick the best but might have ignored (or not known about) polarity hence my signal break-ups??

LarzGearbox

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#651086 5-Jul-2012 08:51

Jaxson:
LarzGearbox: the missus glares at me like it is my fault

It is your fault, you'll never convince her otherwise

Her eyes are like laser beams burning into my head!!

Jaxson

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#651089 5-Jul-2012 08:55

LarzGearbox: I thought it would pick the best but might have ignored (or not known about) polarity hence my signal break-ups??

They shouldn't be 'the best' if the polarity is wrong. As a temporary fix, just go through and delete/hide the channel versions you have identified as being from the worst transmitter.

If each is borderline, then you'll have to address your aerial/distribution system to ensure you are getting a good signal from the aerial, and protecting this signal right down to your unit.

robjg63

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#651095 5-Jul-2012 09:04

LarzGearbox:
Jaxson:
LarzGearbox: the missus glares at me like it is my fault

It is your fault, you'll never convince her otherwise

Her eyes are like laser beams burning into my head!!

Wait for the greatest insult of all - "Do we need to get the man in to sort it out?"

Nothing is impossible for the man who doesn't have to do it himself - A. H. Weiler

sbiddle

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#651103 5-Jul-2012 09:20

Most Freeview approved devices (old Zinwells are a classic example) will only display the strongest signal when it detects the same MUX on multiple frequencies.

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Nety

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#651141 5-Jul-2012 10:29

OK just looked it up and the frequency's are not necessarily from different transmitters. For Fitzherbert TVWork's (TV3 etc) are on 570, TVNZ is on 586 and Kordia is on 602.

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Jaxson

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#651149 5-Jul-2012 10:37

Yeah each of the 3 muxes will be on a different frequency.

Just thinking about it, if the frequency changes have taken effect in your area you will likely end up with the multiple channels you describe, but only one should work.

If this is this case, then perhaps you simply have a reception problem aerial/cable/connections/splitter/amplifier? etc wise and will need to address that. Potentially your existing aerial is not as good on the newer frequencies, or it just needs some attention...

LarzGearbox

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#651155 5-Jul-2012 10:48

Nety: OK just looked it up and the frequency's are not necessarily from different transmitters. For Fitzherbert TVWork's (TV3 etc) are on 570, TVNZ is on 586 and Kordia is on 602.

This is correct, however, I am receiving TVNZ from 586 - i.e. from Fitzherbert but...

am receiving TV3 from 562 - i.e. NOT (570) from fitzherbert (possibly from Kaukau)

Jaxson: Yeah each of the 3 muxes will be on a different frequency.

Just thinking about it, if the frequency changes have taken effect in your area you will likely end up with the multiple channels you describe, but only one should work.

If this is this case, then perhaps you simply have a reception problem aerial/cable/connections/splitter/amplifier? etc wise and will need to address that. Potentially your existing aerial is not as good on the newer frequencies, or it just needs some attention...

The frequency changes have taken effect where I am (Lower Hutt) and TiVo asks you to delete all existing channels on a rescan, which I did - i haven't noticed anything different after the frequency change.

Anyway, I have set all channels to the frequencies from Fitzherbert and will see if I have any issues.

Was just curious to know if there was a logical explanation as to why TiVo decided to pick channels from different transmitters.

Jaxson

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#651160 5-Jul-2012 10:53

LarzGearbox:

Was just curious to know if there was a logical explanation as to why TiVo decided to pick channels from different transmitters.

Given that it didn't delete the old ones automatically after the retune (ie it gave you the option) I think the TIVO is simply configured to store all channel variants. As mentioned above, the official freeview boxes typically pick the strongest, but that's a decision they've made, and the TIVO's approaches this with a different logic is all.