Saorview picture breakup, poor SNR

Turbulent Bill

I'm having issues with picture breakup on Saorview channels (Formuler F1 box with OpenATV 6.1). There was always some weather-dependency with RTE 1 and some other channels, presumably all those on the same mux, but in general was ok. It seems to have gotten worse lately.

The box is now reporting SNRs of around 33% for terrestrial channels, and the breakup occurs when it drops below this. Sat channels are all 85%+ and look perfect.

Any ideas on troubleshooting? My guess here is that the signal strength was always marginal and now has tipped over the edge...

The Cush

What is your aerial setup?

Turbulent Bill

The Cush wrote: »

What is your aerial setup?

External antenna on the side of the house, no idea what type. Almost certain it isn't amplified (need to check).

The Cush

Turbulent Bill wrote: »

External antenna on the side of the house, no idea what type. Almost certain it isn't amplified (need to check).

Generally doesn't need to be amplified. How long is the aerial there?

There could be a number of issues causing this, one that comes to mind is the Saorview frequency changes last March, depending on which transmitter you're on and the the aerial you're using.

https://www.saorview.ie/en/get/coverage

Other issue could include misaligned aerial, damaged cable, water ingress into cable/aerial connection etc.

moro_original

I have noticed that the signal strength from Clermont Carn has dropped significantly.

CH42 is still good (mux with RTE2), but CH45 (mux with RTE1) has gone from perfect to extremely weak in the last few days. I'm just north of Belfast.

I've an SDR which confirms that relative to each other (and some Freeview muxes), the mux on CH45 is now much weaker than it was back in March 2020. I wonder if there have been any works on the transmitter?

Turbulent Bill

The Cush wrote: »

Generally doesn't need to be amplified. How long is the aerial there?

There could be a number of issues causing this, one that comes to mind is the Saorview frequency changes last March, depending on which transmitter you're on and the the aerial you're using.

https://www.saorview.ie/en/get/coverage

Other issue could include misaligned aerial, damaged cable, water ingress into cable/aerial connection etc.

Aerial is installed about 5 years. There's no obvious damage that I can see. Checked the aerial alignment angle with what the Saorview coverage map shows, looks like it's off by about 15 degrees. However, the house orientation might block better alignment, might experiment with this if the weather is suitable.

Using Auto Bouquets Maker to do the tuning, with the latest providers info, hopefully this is enough? Thanks for the pointers.

Turbulent Bill

moro_original wrote: »

I have noticed that the signal strength from Clermont Carn has dropped significantly.

CH42 is still good (mux with RTE2), but CH45 (mux with RTE1) has gone from perfect to extremely weak in the last few days. I'm just north of Belfast.

I've an SDR which confirms that relative to each other (and some Freeview muxes), the mux on CH45 is now much weaker than it was back in March 2020. I wonder if there have been any works on the transmitter?

I'm in North Dublin, trying to receive from Kippure.

Elvis Hammond

Turbulent Bill wrote: »

I'm having issues with picture breakup on Saorview channels (Formuler F1 box with OpenATV 6.1). There was always some weather-dependency with RTE 1 and some other channels, presumably all those on the same mux, but in general was ok. It seems to have gotten worse lately.

The box is now reporting SNRs of around 33% for terrestrial channels, and the breakup occurs when it drops below this. Sat channels are all 85%+ and look perfect.

Any ideas on troubleshooting? My guess here is that the signal strength was always marginal and now has tipped over the edge...

Yes, l'd say the signal was always marginal; there certainly shouldn't be 'weather dependency', unless for the odd time when atmospheric conditions bring in distant interfering signals.

Is this one of those installations where the aerial has been put beside the dish for installer convenience, hoping they'll get away with it signal wise?

Also add the fact that Kippure's frequency change was fairly wide, going from mid 50s to mid 30s.

Turbulent Bill

Can anyone recommend an installer who covers North Dublin who could look at this?

decor58

Turbulent Bill wrote: »

Can anyone recommend an installer who covers North Dublin who could look at this?

Sorry, but why Kippure, why not Three Rock, on Ch 30 & 33. I work in the city centre, we have 3 tv's and all are tuned to Three Rock, I live in Bray and get a better signal from Three Rock than from Kippure.

Elvis Hammond

Maybe the 15 degrees he mentions above means his aerial was actually installed to receive from Three Rock.

Turbulent Bill

Elvis Hammond wrote: »

Is this one of those installations where the aerial has been put beside the dish for installer convenience, hoping they'll get away with it signal wise?

To close out this thread, that's exactly what happened. The dish and aerial were co-located, but turns out that the signal strength was never sufficient there. A different aerial location, and an amp, were needed to get decent performance.