Should the multipath field ensembles be tested at all RF frequencies? Do the single static echo tests have to be performed at all RF frequencies?
The law requires converter boxes to contain features or functions necessary to “enable a consumer to convert any channel broadcast in the digital television service into a format that the consumer can display on television receivers designed to receive and display signals only in the analog television service.” Therefore, the intent of all of the RF specifications is that the requirements be met on every applicable TV channel. While equalizer performance is unlikely to be directly affected by the channel selection on the TV, channel-dependent (i.e., frequency-dependent) signal impairments introduced by the tuner could cause a failure to correctly process field ensembles or single static echoes that might otherwise marginally pass the specification. Consequently, it is recommended that the manufacturer perform tests using channel selections that maximize signal impairments in the tuner, based on knowledge of the design of the tuner. For example, manufacturers may choose to submit test r
