Just Sharing This 700Mhz clearance and potential interference to your TV

rolfw

rolfw

Believe it when I see it Admin.
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Derbyshire
Hot on the heels of the 800 Mhz band clearance and the fitting of filters t0 prevent LTE TV interference, the 700 Mhz clearance is kicking off shortly, starting in Scotland.

This may involve the fitting of a masthead or set back filter, even if you've already had one fitted to remedy 4G interference from the recent 800Mhz clearance. If you receive your signal from a transmitter which uses frequencies close to the 700 Mhz band, then there is potential for renewed interference.

Digital UK | 700MHz clearance



Ofcom_700MHz-clearance-rollout_map.jpg
 
Ah 2020 before it affects me unless I move of course
 
2019 here, but, I haven't plugged my home-made, tuned for about 746MHz aerial back into my TV in over a year, just haven't felt the need to watch the dross shown on TV these days, ironic given I'm still here on a TV reception related forum... :-rofl2
 
2020 here but it wont affect me cause i have satellite.
 
John Pykett said:
but its really skys end that they will sort but for my end nah
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A very narrow minded view. It is not just Sky but most broadcasters. The need to replace equipment before its due date will cost a lot of money which will cut back on the money available for content and may well tip some smaller broadcasters into closing down - so it will affect you in what you watch.
 
davemurgtroyd said:
A very narrow minded view. It is not just Sky but most broadcasters. The need to replace equipment before its due date will cost a lot of money which will cut back on the money available for content and may well tip some smaller broadcasters into closing down - so it will affect you in what you watch.
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i dont really care in what i watch as long there is something to watch
 
Next year for us here! Malvern will have big changes as the channels used go up to 60.

We already have a fairly substantial filter to stop the HD channels on Channel 60 from breaking up due to a tower block with 800MHz LTE antennas on top of it a few hundred metres away directly in line with the transmitter.
 
Question:
I set Ch 58 (767.25/ 773.25 MHz) on the Sky box as the RF2 o/p for the house wired distribution system via a Loftbox, which also has the local UHF Band A transmitter channels I/P from the terrestrial Band A (& so not wideband) antenna. So does anyone think I now need to add an additional 700+ MHz filter between the antenna and the Loftbox?

OTOH, could I just retune the Sky box o/p to another lower frequency channel - but that's a slight hassle (and would it "solve" the potential problem, or would the 700+ MHz signals still cause problems anyway?) :eek:
 
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After the 600MHz sell off around 2025/2030 this will leave just 10 Terrestrial frequencies for DTT TV so it will probably be back to what we had on Analogue in the 70's with just 4 to 9 analogue TV channels depending on your location back in the late 60's on the North Norfolk coast I was able to get Yorkshire ITV, & even Grampian ITV with a home made 10 element band II vertical VHF aerial :)

Because the mobile Broadband companies have bigger wallets than the DTT companies all that will be left is Free-Sat tv hopefully :eek:
 
jeallen01 said:
Question:
I set Ch 58 (767.25/ 773.25 MHz) on the Sky box as the RF2 o/p for the house wired distribution system via a Loftbox, which also has the local UHF Band A transmitter channels I/P from the terrestrial Band A (& so not wideband) antenna. So does anyone think I now need to add an additional 700+ MHz filter between the antenna and the Loftbox?

OTOH, could I just retune the Sky box o/p to another lower frequency channel - but that's a slight hassle (and would it "solve" the potential problem, or would the 700+ MHz signals still cause problems anyway?) :eek:
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Channel 36 should still be clear for Sky digibox modulator, but if as you suggest, you add a 700 Mhz filter on the aerial input, that should do the trick, as long as you don't update the loftbox to one with 700 Mhz filtering.
 
rolfw said:
Channel 36 should still be clear for Sky digibox modulator, but if as you suggest, you add a 700 Mhz filter on the aerial input, that should do the trick, as long as you don't update the loftbox to one with 700 Mhz filtering.
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Rolf

Many Thanks, but, based on William's post, I think the filter will probably need to be 600+ MHz.

OTOH, Ch 36 appears to be 602/ 603.25/ 602.31/ 607.75 MHz (according to Wikipedia) , so even that one may not be "safe".
 
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If you filter 600 upwards to hedge against future clearance, depending where you are, you'll filter out current TV channels, as the 600s will be still in use, similarly, it would have been easier for me to filter out 700 Mhz when I did the 800 Mhz installations, but then my customers would have lost most of their channels.
 
There are plenty of aerials around here pointing towards Guildford. It's going to be an interesting year.
 
rolfw said:
If you filter 600 upwards to hedge against future clearance, depending where you are, you'll filter out current TV channels, as the 600s will be still in use, similarly, it would have been easier for me to filter out 700 Mhz when I did the 800 Mhz installations, but then my customers would have lost most of their channels.
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We are in a Band A area with the antenna pointed at Crystal Palace, so anything above Ch 36 is not relevant - but here is one list that I just found on UKFreetv which shows the changes we will be getting
upload_2017-7-21_8-30-16.webp
There are already some filters available to (hopefully!) stop everything above Ch36/37, but it looks like a lot more will be needed, and possibly with a much sharper cutoff above Ch 30. OTOH the effects in areas now using higher Ch nos will be much more dramatic, with new Group A antennas to replace the existing ones?
 
Odd, from that chart it suggests the cutoff is at Channel 31, and yet Channel 35 (active T2 transmissions on Crystal Palace) is under 600MHz
 
Channel Hopper said:
Odd, from that chart it suggests the cutoff is at Channel 31, and yet Channel 35 (active T2 transmissions on Crystal Palace) is under 600MHz
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CH
I see what you mean - so maybe that page I found is not correct or will it be that the "600 MHz" figure be rather "flexible"?
 
According to the Ofcom study, 600MHz does not actually mean 600MHz cutoff

The 600 MHz spectrum covers the range 550 to 606 MHz comprising seven 8 MHz
channels (channels 31 to 37) . The band was cleared of analogue TV on a region by
region basis during digital switch -over (DSO ). That process was completed in 2012

https://www.ofcom.org.uk/__data/assets/pdf_file/0026/42965/condoc.pdf

More info inside but it is a long read.
 
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