The previous Comcast "installer" showed up with a two-way splitter that had the appearance of being mass-purchased at a Chinese garage sale. No indications as to bandpass or to db losses in each output. Anyway, he was unable to complete the high-speed Internet connection, and left with the splitter still in his pocket.
In our local electronics shop, I've seen two-way RCA digital splitters,
5 MHz to 1 GHx, with -3.5 db loss claimed for each output, and another splitter claiming 5 MHz to 2.3 GHz.
Which (or what) should I look for (splitter specs) when the next "installer" comes to hook up my high-speed Internet connection?
BTW: Our home is already completely wired with RG6, and I've tested each outlet, using a TV set from Channel 2 to Channel 99, to ensure good connections.
Just to clarify your clarification, a digital cable box is only needed if you want to watch the digital version of the channel. Simulating means that the analog versions are still there, and can still be received by any cable ready consumer equipment.
This also varies by market, as Comcast has not turned on digital simulating in all of their markets.
Digital can use any frequency. Some digital channels on my system are on 117MHz, analog 99, which is just below analog 14 in the complicated channel/frequency relationship (2-4, 5-6, 95-99, 14-22, 7-13, 23-94,
The channel numbers on a cable box can be programmed to anything, analog or digital. As mentioned elsewhere, Digital Simulcasting is being rolled out at various levels across the country. The box can be programmed to use the digital version instead of the analog when you choose a channel. This isn't limited to digital. Numbers for analog channels can point to different analog frequencies that 'standard.'
The box does not automatically select anything. The headend sends a "channel map" to each and every digital set-top box. The channel map establishes the relationship between logical channel numbers and actual frequencies. The map says if the channel is analog or digital. For digital channels, it also identifies the individual streams within an RF channel.
When a user selects a channel number, the box consults the channel map to determine what frequency to tune to. If the channel is analog, the box uses the analog demodulator and to recover the signal. If the channel is digital, the digital demodulator and decryptor are used. Further, the channel map identifies the stream within the digital channel for the selected program.
When a digital simulcast is used, the analog program stays on the same frequency its always been on. This way, cable ready TVs and VCRs can continue to access it on the same channel number. The digital version of the program is on a different frequency, but the channel map causes the set-top box to make it appear at the same logical channel number.
Note that an RF channel can carry 6 or more standard definition video programs in digital format. This is why cable companies really want to switch to all digital, as it allows for more services with the same number of RF channels.
If you're unsure if a particular channel is analog or digital, use the Motorola diagnostics to figure out what is going on. Tune to a channel, turn the box off and within 5 seconds press "ok/select" on the remote. This will get you into the diagnostic menu. "Inband Status" provides information on the last channel tuned, including if it is analog or digital (QAM64/QAM256).