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Recently recorded programme using a Humax HDR T2 from BBC4.
When played back there were many breaks in transmission.
Just looked at the signal strength on the TV & it shows BBC1 as 87% but BBC4 as 75%, I’m on the Tacolneston transmitter
Is this normal?
It’s normal for different mux to have different signal strengths. Your aerial doesn’t have the same gain at different frequencies. The more important number is signal quality, this should not fluctuate wildly and be as close to 100% as possible.
In addition some of the MUX are transmitted at a lower power – Were you recording BBC 4 HD ? If so the COM 7 MUX is at a lower power than the others.
BBC 4 SD 100,000W (PSB1) BBC 4 HD 27,400W (COM7)
https://ukfree.tv/transmitters/tv/Tacolneston
Your signal strength is higher than mine but I have 100% quality on every mux.
You don’t say when you recorded the content, it may have been during a high pressure lift period and the issue was down to co channel interference (CCI).
https://www.radioandtvhelp.co.uk/interference/rtis_tv/weather_digitalTV
Graham,
Many thanks
My signal qualities are also 100% which is good.
Yes, I was recording in BBC4HD
Looking at the TV signal area it says for BBC1HD 706000KHz,8MHz,32K,1/128
& for BBC4 HD 554000KHz,8 MHz,32K,1/128
Does this mean that the BBC4HD is 152000KHz less power than BBC1HD?
johnooooo – 10 minutes ago »
Graham,
Many thanks
My signal qualities are also 100% which is good.
Yes, I was recording in BBC4HD
Looking at the TV signal area it says for BBC1HD 706000KHz,8MHz,32K,1/128
& for BBC4 HD 554000KHz,8 MHz,32K,1/128
Does this mean that the BBC4HD is 152000KHz less power than BBC1HD?
You are confusing the UHF frequency used for the Mux carrier. Power is measured in Watts (1kW is 1000 Watts), the erp (estimated radiating power) for each Tacolneston Mux is shown on the link I posted above.
BBC1 – HD uses 706MHz (706,000kHz) (UHF Channel 50) at 100kW power , BBC4-HD uses 554MHz (UHF Channel 31) at 27.4kW).
Com 7 is very susceptible to CCI due to it’s low power, so fairly confident your recording problems were weather related.
OK, thanks, I’ll just put up with the odd inconvenience.
johnooooo – 23 minutes ago »
OK, thanks, I’ll just put up with the odd inconvenience.
Channel 4 SD will most likely be fine, if you have the tuners you could record both when high pressure is forecast.
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