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You must live in a relatively interference free zone.
Poorly suppressed vehicles and electrical equipment can cause picture breakup with traditional coax.
My problem isn’t helped by that fact that the UHF socket on my Samsung TV is just below the HDMI ports I didn’t have an issue with the old Sony TV which had plenty of space between the HDMI and UHF sockets.
JohnH77 – 1 hour ago »
You must live in a relatively interference free zone.
Poorly suppressed vehicles and electrical equipment can cause picture breakup with traditional coax.
I don’t doubt that they can. My qualifications in Electronics and 40 years experience in Telecomms, Engineering and Computing tell me it is so. However, brown co-ax is not useless for Freeview in every environment. BTW, I live alongside a fairly busy road. No problems.
grahamlthompson – 1 week ago »
giskard – 23 minutes ago »
grahamlthompson – 5 months ago »
giskard – 13 hours ago »
giskard – 4 weeks ago »
A1944 – 1 day ago »
Maybe once the Humax is on there is interference from the HDMI cable into the TV’s aerial cable. Try moving them as far apart as you can.
Did that and it seems to have made a difference. Time to replace the HDMI cable I think.
HDMI cable replaced and moved as far away from aerial lead as possible, but it’s still an issue although now it’s intermittent when the Humax is powered on.
Could my FVP-5000 be faulty? Surely it shouldn’t be generating so much interference that it affects the TV signal?
HDMI cables generate RF in the UHF band, it’s nothing to do with the box. If you have cheap poorly screened coax interconnects it can knock out terrestrial TV. Make your own coax interconnects using double screened satellite grade cable.
I use screw on f connectors and belling lee converters as needed.
https://www.screwfix.com/p/labgear-pf100-satellite-coaxial-cable-25m-black/58592
https://www.screwfix.com/p/philex-coaxial-f-plug-pack-of-10/17061
https://www.screwfix.com/p/labgear-f-to-coax-plugs-pack-of-10/39772
https://www.screwfix.com/p/labgear-f-to-coax-adaptors-pack-of-10/33532
Thanks for that, very useful.
So I should use double-screened co-ax between my aerial point and the Humax, and from the Humax to the TV?
Yes it can avoid interference from HDMI interconnects which radiate radio frequency interference in the same band (uhf) as terrestrial TV as described above. However I would use a splitter to give the TV and Humax box a seperate feed. That way you can turn on power saving in sby mode.
https://www.screwfix.com/p/labgear-2-way-splitter-with-power-pass-all-ports/99105
Well I did all of the above and made my own solid-core coax leads to use with the Labgear splitter and it seems to have resolved the issue. The TV seemed to lose signal a bit after plugging everything in but after retuning it, it seems to be fixed. The only thing that concerns me is that doing a signal test on the FVP-5000T shows that tuner 2 only has 70% signal quality in contrast with the tuner 1 which is at 98%.
giskard – 3 hours ago »
grahamlthompson – 1 week ago »
giskard – 23 minutes ago »
grahamlthompson – 5 months ago »
giskard – 13 hours ago »
giskard – 4 weeks ago »
A1944 – 1 day ago »
Maybe once the Humax is on there is interference from the HDMI cable into the TV’s aerial cable. Try moving them as far apart as you can.
Did that and it seems to have made a difference. Time to replace the HDMI cable I think.
HDMI cable replaced and moved as far away from aerial lead as possible, but it’s still an issue although now it’s intermittent when the Humax is powered on.
Could my FVP-5000 be faulty? Surely it shouldn’t be generating so much interference that it affects the TV signal?
HDMI cables generate RF in the UHF band, it’s nothing to do with the box. If you have cheap poorly screened coax interconnects it can knock out terrestrial TV. Make your own coax interconnects using double screened satellite grade cable.
I use screw on f connectors and belling lee converters as needed.
https://www.screwfix.com/p/labgear-pf100-satellite-coaxial-cable-25m-black/58592
https://www.screwfix.com/p/philex-coaxial-f-plug-pack-of-10/17061
https://www.screwfix.com/p/labgear-f-to-coax-plugs-pack-of-10/39772
https://www.screwfix.com/p/labgear-f-to-coax-adaptors-pack-of-10/33532
Thanks for that, very useful.
So I should use double-screened co-ax between my aerial point and the Humax, and from the Humax to the TV?
Yes it can avoid interference from HDMI interconnects which radiate radio frequency interference in the same band (uhf) as terrestrial TV as described above. However I would use a splitter to give the TV and Humax box a seperate feed. That way you can turn on power saving in sby mode.
https://www.screwfix.com/p/labgear-2-way-splitter-with-power-pass-all-ports/99105
Well I did all of the above and made my own solid-core coax leads to use with the Labgear splitter and it seems to have resolved the issue. The TV seemed to lose signal a bit after plugging everything in but after retuning it, it seems to be fixed. The only thing that concerns me is that doing a signal test on the FVP-5000T shows that tuner 2 only has 70% signal quality in contrast with the tuner 1 which is at 98%.
the signal strength will vary with Mux and also some use reduced power. No aerial has a completely flat gain curve with frequency. To test the second tuner on the same MUX you will need firstly to set two recordings on the same mux to fully utilise tuner 1 and then view a 3rd channel on the same mux.
Try recording BBC 1 – HD 101, BBC – 2 HD and then tune to one of the remaining PSB 3 channels 103, 104 or 105,
What signal strength is now shown ? incidentally if a steady 100% quality is shown the signal strength is irrelevant.
grahamlthompson – 5 hours ago »
the signal strength will vary with Mux and also some use reduced power. No aerial has a completely flat gain curve with frequency. To test the second tuner on the same MUX you will need firstly to set two recordings on the same mux to fully utilise tuner 1 and then view a 3rd channel on the same mux.
Try recording BBC 1 – HD 101, BBC – 2 HD and then tune to one of the remaining PSB 3 channels 103, 104 or 105,
What signal strength is now shown ? incidentally if a steady 100% quality is shown the signal strength is irrelevant.
When recording various channels and watching another, the signal strength on each tuner is 87%, 73% and 43% respectively, quality on each is 100%, so from what you’ve said all is fine
giskard – 8 hours ago »
grahamlthompson – 5 hours ago »
the signal strength will vary with Mux and also some use reduced power. No aerial has a completely flat gain curve with frequency. To test the second tuner on the same MUX you will need firstly to set two recordings on the same mux to fully utilise tuner 1 and then view a 3rd channel on the same mux.
Try recording BBC 1 – HD 101, BBC – 2 HD and then tune to one of the remaining PSB 3 channels 103, 104 or 105,
What signal strength is now shown ? incidentally if a steady 100% quality is shown the signal strength is irrelevant.
When recording various channels and watching another, the signal strength on each tuner is 87%, 73% and 43% respectively, quality on each is 100%, so from what you’ve said all is fine
The signal levels you quote don’t really tell us much without knowing which channels (or rather the MUX) you were using at the time.
Without knowing this no way to see if the 43% is purely a low power Mux (eg Com 7 or COM
.
grahamlthompson – 3 minutes ago »
The signal levels you quote don’t really tell us much without knowing which channels (or rather the MUX) you were using at the time.
Without knowing this no way to see if the 43% is purely a low power Mux (eg Com 7 or COM
.Recording on BBC1 HD and BBC2 HD and watching ITV HD only tuner one was being used so I started a recording on C4HD and switched channel to one of the more obscure ones, which I’d guess is the one tuned on the third tuner.
giskard – 9 hours ago »
grahamlthompson – 3 minutes ago »
The signal levels you quote don’t really tell us much without knowing which channels (or rather the MUX) you were using at the time.
Without knowing this no way to see if the 43% is purely a low power Mux (eg Com 7 or COM
.Recording on BBC1 HD and BBC2 HD and watching ITV HD only tuner one was being used so I started a recording on C4HD and switched channel to one of the more obscure ones, which I’d guess is the one tuned on the third tuner.
Not sure recording two from same Mux and watching a 3rd even from same mux is possible using only one tuner. Not at home so can’t check till Thursday.
Two recordings tuner 1, ITV HD View and Record CH 4 HD tuner 2 and obscure viewed tuner 3. Unit will record up to 4 channels across two MUX.
Tuner 1 and 2 should have same signal strength as only 1 Mux is used.
In my days when working on Canberra & “V” bombers the way to cut cross talk was to disconnect on end of the screen to stop circulating currents.
If there was this much of a problem with bog standard co-ax I’m sure there would be much more Hoo-Ha about it
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