HDMI cables are a well known but, I suspect, a not well understood source of interference to digital TV, so it may be connected with that.
My Humax Forum » Freeview HD » HD FOX T2
Where is BBC4 HD?
(30 posts)-
| Thu 29 Mar 2018 14:58:52 #21 |
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Faust - 3 hours ago »
I have cured the low signal quality issue with my Youview box on COM 7/8 and the solution has really surprised me.
I was round the back of the TV messing with the cables trying to find a solution to the poor signal quality. In order to move one of the cables I had to unplug my Chromecast from the USB port on the Youview box. As soon as I did this I saw the signal quality meter for BBC News HD jump from 15% to 97%.
I thought at first it might have been because I had moved a cable. However, the second I plugged the Chromecast back into the PVR the SQ dropped to 15% again. I tried using the 'wallwart' instead of the USB port but this didn't make any difference. I then moved the Chromecast from the HDMI switch (situated near the PVR) and plugged it directly into HDMI-4 on the TV, which is approx 30 inches from the PVR. The second I did this the SQ jumped straight back to 97%, so obviously Chromecast is the issue.
I'm surprised by this though as the Freeview signal is not on 2.4GHz. Still, it's a result and I'm now getting good SQ on all muxes from the Humax.
I do wonder if the DTR 2100 is not particularly well screened being in this small plastic box.Relocate the chromecast using a hdmi extender cable. I would change the interconnects with ones made from WF100/PF100 satellite grade cable.
It's pretty common for hdmi connections to knock out signals when cheap poorly screened coax is used for the RF connections. HDMI radiates in the UHF band at varying frequencies depending on the current video being output.
Screwfix sell PF100, screw on f connectors and F to Belling Lee male and female adaptors.
| Thu 29 Mar 2018 15:58:19 #22 | -
Try charging / powering another device such as your mobile phone off the USB socket on the Youview box. You may well find that causes the signal to drop as it is the USB circuitry causing interference, not the HDMI circuitry.
| Thu 29 Mar 2018 16:45:18 #23 | -
I am on Crystal Palace - I lost 106, and other channels, with the upgrade on my 2 year old Freeview Play TV and my Fox T2 PVR.
The T2 PVR died when I did a factory reset, so I bought an FVP-5000T - that also is short some channels, but interestingly fewer than the TV -106 loss is common to both.
After a 15 minute wait for the Freeview helpdesk, and a pointless conversation, a visit from an engineer was scheduled, who didn't turn up, and has been rescheduled for a fortnight.
The helpdesk point to re-programming. reset and new aerials. My Aerial is not brand new, but is Wideband. They now admit that about 2 out of 10 users are having problems and will need a fix of some sort - to be determined.
They seem to have caused significant problems with this - seemingly to free capacity for mobile phones.
| Thu 29 Mar 2018 20:28:30 #24 | -
grahamlthompson - 5 hours ago »
Faust - 3 hours ago »
I have cured the low signal quality issue with my Youview box on COM 7/8 and the solution has really surprised me.
I was round the back of the TV messing with the cables trying to find a solution to the poor signal quality. In order to move one of the cables I had to unplug my Chromecast from the USB port on the Youview box. As soon as I did this I saw the signal quality meter for BBC News HD jump from 15% to 97%.
I thought at first it might have been because I had moved a cable. However, the second I plugged the Chromecast back into the PVR the SQ dropped to 15% again. I tried using the 'wallwart' instead of the USB port but this didn't make any difference. I then moved the Chromecast from the HDMI switch (situated near the PVR) and plugged it directly into HDMI-4 on the TV, which is approx 30 inches from the PVR. The second I did this the SQ jumped straight back to 97%, so obviously Chromecast is the issue.
I'm surprised by this though as the Freeview signal is not on 2.4GHz. Still, it's a result and I'm now getting good SQ on all muxes from the Humax.
I do wonder if the DTR 2100 is not particularly well screened being in this small plastic box.Relocate the chromecast using a hdmi extender cable. I would change the interconnects with ones made from WF100/PF100 satellite grade cable.
https://www.amazon.co.uk/dp/B01N2B7TBR/ref=asc_df_B01N2B7TBR51238836/?tag=googshopuk-21&creative=22146&creativeASIN=B01N2B7TBR&linkCode=df0&hvadid=205210909091&hvpos=1o1&hvnetw=g&hvrand=13066779179558089665&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9041125&hvtargid=pla-420481173806
It's pretty common for hdmi connections to knock out signals when cheap poorly screened coax is used for the RF connections. HDMI radiates in the UHF band at varying frequencies depending on the current video being output.
Screwfix sell PF100, screw on f connectors and F to Belling Lee male and female adaptors.There is no HDMI cable for the Chromecast (it's the original one BTW) as it simply plugs into a HDMI port. Now I have moved it to HDMI-4 on the TV the Freeview signal is up at between 95 - 100% on all muxes. It was previously in a HDMI switch along with a couple of other devices around 6 inches from the PVR.
The aerial leads are brand new. The aerial installer made me up a couple of leads last week using the black sat cable including new Belling-Lee connectors.
The TV's tuner wasn't experiencing any issues before and isn't now despite the Chromecast now being plugged directly into the back of the TV. It's either a more resilient tuner or the TV is better screened. It was just sheer chance that I found the culprit as I would never have suspected the Chromecast.
| Thu 29 Mar 2018 21:39:54 #25 | -
gomezz - 4 hours ago »
Try charging / powering another device such as your mobile phone off the USB socket on the Youview box. You may well find that causes the signal to drop as it is the USB circuitry causing interference, not the HDMI circuitry.As said in my previous post I tried powering the Chromecast from the supplied PSU instead, but this made no difference. What made the difference was moving the Chromecast away from the Humax. I'm still using the USB from the Humax to power the Chromecast and it's causing no problems whatsoever.
I suspect that when/if COM 7 and COM 8 go on full power, having the Chromecast near the Humax wouldn't be such an issue or maybe no longer an issue at all.
| Thu 29 Mar 2018 21:48:58 #26 | -
Faust - 11 hours ago »
gomezz - 4 hours ago »
Try charging / powering another device such as your mobile phone off the USB socket on the Youview box. You may well find that causes the signal to drop as it is the USB circuitry causing interference, not the HDMI circuitry.As said in my previous post I tried powering the Chromecast from the supplied PSU instead, but this made no difference. What made the difference was moving the Chromecast away from the Humax. I'm still using the USB from the Humax to power the Chromecast and it's causing no problems whatsoever.
I suspect that when/if COM 7 and COM 8 go on full power, having the Chromecast near the Humax wouldn't be such an issue or maybe no longer an issue at all.There are no plans afaik to increase the power of COM 7 and COM 8. They are due to close in the next year or so anyway.
| Fri 30 Mar 2018 9:19:39 #27 | -
grahamlthompson - 5 hours ago »
Faust - 11 hours ago »
gomezz - 4 hours ago »
Try charging / powering another device such as your mobile phone off the USB socket on the Youview box. You may well find that causes the signal to drop as it is the USB circuitry causing interference, not the HDMI circuitry.As said in my previous post I tried powering the Chromecast from the supplied PSU instead, but this made no difference. What made the difference was moving the Chromecast away from the Humax. I'm still using the USB from the Humax to power the Chromecast and it's causing no problems whatsoever.
I suspect that when/if COM 7 and COM 8 go on full power, having the Chromecast near the Humax wouldn't be such an issue or maybe no longer an issue at all.There are no plans afaik to increase the power of COM 7 and COM 8. They are due to close in the next year or so anyway.
Definitely some sort of issue with HDMI though Graham. I noticed that even when turning on the Freesat Box (HDR-1000s) the signal quality on the Youview would drop away rapidly.
Funny thing is though it is only an issue on COM 7 Channel 55 at 746000khz. COM 8 Channel 56 754000kHz actually has a poorer signal strength but better signal quality and is not affected by Chromecast or HDMI at all.
I have ended up changing what was supposed to be a better quality HDMI lead for a relative cheapo and that has cured the problem.
There must be something about the 746000kHz frequency that is susceptible to interference though.
| Fri 30 Mar 2018 15:31:02 #28 | -
Faust - 2 minutes ago »
grahamlthompson - 5 hours ago »
Faust - 11 hours ago »
gomezz - 4 hours ago »
Try charging / powering another device such as your mobile phone off the USB socket on the Youview box. You may well find that causes the signal to drop as it is the USB circuitry causing interference, not the HDMI circuitry.As said in my previous post I tried powering the Chromecast from the supplied PSU instead, but this made no difference. What made the difference was moving the Chromecast away from the Humax. I'm still using the USB from the Humax to power the Chromecast and it's causing no problems whatsoever.
I suspect that when/if COM 7 and COM 8 go on full power, having the Chromecast near the Humax wouldn't be such an issue or maybe no longer an issue at all.There are no plans afaik to increase the power of COM 7 and COM 8. They are due to close in the next year or so anyway.
Definitely some sort of issue with HDMI though Graham. I noticed that even when turning on the Freesat Box (HDR-1000s) the signal quality on the Youview would drop away rapidly.
Funny thing is though it is only an issue on COM 7 Channel 55 at 746000khz. COM 8 Channel 56 754000kHz actually has a poorer signal strength but better signal quality and is not affected by Chromecast or HDMI at all.
I have ended up changing what was supposed to be a better quality HDMI lead for a relative cheapo and that has cured the problem.
There must be something about the 746000kHz frequency that is susceptible to interference though.Change your coax interconnects to home made ones using 100 grade satellite cables.
| Fri 30 Mar 2018 15:35:35 #29 | -
grahamlthompson - 17 minutes ago »
Faust - 2 minutes ago »
grahamlthompson - 5 hours ago »
Faust - 11 hours ago »
gomezz - 4 hours ago »
Try charging / powering another device such as your mobile phone off the USB socket on the Youview box. You may well find that causes the signal to drop as it is the USB circuitry causing interference, not the HDMI circuitry.As said in my previous post I tried powering the Chromecast from the supplied PSU instead, but this made no difference. What made the difference was moving the Chromecast away from the Humax. I'm still using the USB from the Humax to power the Chromecast and it's causing no problems whatsoever.
I suspect that when/if COM 7 and COM 8 go on full power, having the Chromecast near the Humax wouldn't be such an issue or maybe no longer an issue at all.There are no plans afaik to increase the power of COM 7 and COM 8. They are due to close in the next year or so anyway.
Definitely some sort of issue with HDMI though Graham. I noticed that even when turning on the Freesat Box (HDR-1000s) the signal quality on the Youview would drop away rapidly.
Funny thing is though it is only an issue on COM 7 Channel 55 at 746000khz. COM 8 Channel 56 754000kHz actually has a poorer signal strength but better signal quality and is not affected by Chromecast or HDMI at all.
I have ended up changing what was supposed to be a better quality HDMI lead for a relative cheapo and that has cured the problem.
There must be something about the 746000kHz frequency that is susceptible to interference though.Change your coax interconnects to home made ones using 100 grade satellite cables.
As said in previous post Graham the leads were only made up last week by the aerial installer - he used sat cable and new Belling Lee connectors. I have also tried a couple of older home made leads (the old brown cable) with identical results. Unplugging the HDMI lead from the 100OS restored the SQ to the Youview box instantly as did switching it off.
| Fri 30 Mar 2018 16:03:32 #30 |
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