I can confirm that there have been a number of occasions on which the COM7 channel from Mendip appears to be absent (or at least is undecodable).Now I see that COM7 is transmitted as an SFN I can understand why it may disappear from time to time, due to ducting from other more distant transmitters, as the other sites may be far enough away to exceed the COFDM guard interval of the multiplex. I note that today in Burnham-on-Sea it is giving a 100% quality rating and zero errors ( I assume that the error rate of my TV is calculated after FEC has been applied). It will be interesting to see how this varies with the weather, if it ever gets warm again!
Sunday 20 June 2021 3:07PM
I can confirm that there have been a number of occasions on which the COM7 channel from Mendip appears to be absent (or at least is undecodable).Now I see that COM7 is transmitted as an SFN I can understand why it may disappear from time to time, due to ducting from other more distant transmitters, as the other sites may be far enough away to exceed the COFDM guard interval of the multiplex. I note that today in Burnham-on-Sea it is giving a 100% quality rating and zero errors ( I assume that the error rate of my TV is calculated after FEC has been applied). It will be interesting to see how this varies with the weather, if it ever gets warm again!