Re: Why is video inverted for transmission?

TV

You're an idiot. An HDTV TUNER that ALSO puts out onto 4:3 TVs IS a converter, you retarded f*****ad!

I have owned mine for nearly three years, and you are an utter retard, as usual.

ChairmanOfTheBored wrote in news: snipped-for-privacy@4ax.com:

It depends on your perspective.

Such boxes are technically tuners that output the signle tuned channel. They are not "convertors" in the sense they do not convert all the digital channels to analog for an older TV to tune.

is

retard,

Again perspective.

Digital OTA tuners have been sold for years now. It is just the voucher program is not in effect yet, and I don't think that voucher eligble tuners are in stores yet.

Gary Tait wrote: (snip)

I remember in the days of UHF getting more popular, and using a converter box that output on VHF channel 3. This can be done with the appropriate mixer and LO, without converting the input to baseband. It does involve tuned circuits, but does not convert all (70) UHF channels to be tuned on a (12 channel) VHF tuner.

I believe there were/are block converters from cable channels to UHF which do convert all at once. Most cable boxes don't do that, though. Early (analog) ones did the down conversion similar to the UHF conversion described above. Most now likely go to baseband and then remodulate for those without video inputs.

The distinction between 'tuner' and 'converter' is fuzzy. I don't believe that there is a convenient way to block convert the ATSC input to NTSC output. One could build a box with multiple tuners, decoders, and modulators but I doubt that would be for the consumer market.

The box needs an ATSC tuner, and the logic to convert the result to an NTSC analog signal. Most likely with both video and RF outputs. The output of the ATSC tuner is the digital signal, not suitable for an analog TV, so the box needs both a tuner and converter.

-- glen

glen herrmannsfeldt snipped-for-privacy@ugcs.caltech.edu posted to sci.electronics.design:

While i have not see one, there is nothing that prevents it technologically. I have seen receivers that can receive the entire AM band (in stereo as broadcast) at the same time. I have seen receivers that receive over half of the FM band (in stereo) simultaneously. Only ADC, DAC, and compute power available preclude block conversion. Dig around bit on software defined radios and you can find the done devices that i have found.

Which is why the item I describe IS a converter!

Mainly... because it HAS ONE IN IT!

You have a prick, therefore you are a prick? Maybe so.

Jerry

glen herrmannsfeldt wrote in news:OrqdnQBYdfUnjpDanZ2dnUVZ snipped-for-privacy@comcast.com:

channel.

Yes, that is a traditional cable convertor, which wen out of fasion when integrated descramblers came to be. Even the tuner block in an analog TV is a sort of frequency convertor, it just converts the incoming RF channel to an IF, which the circuits detect the video baseband from.

Yes, there were block upconvertors, which converted a block of cable channels to UHF frequencies.

Modern digital cable and satellite boxes (and late era analog cable tuner/descramblers) output composite video/stereo audio, not baseband. Baseband is the signal that comes off the primary video detector, and has the audio subcarrier (s) on it still. Those signals are filtered off and the signal clamped to make composite video. Digital boxes just make the composite or other video signal from the data from the video deocder.

A convertor just converts frequency. A tuner tunes a signal an outputs "line" video and audio.

Not for a $40 box.

All ATSC tuner boxes do that now. They tune the ATSC hannel and output a viewiable SD or HD video signal. Some may lack RF out though.

It is just they have to make one that meets the requirements for a voucher (which has certain stipulations an STB manufacturer could easily meet, and some boxes could likely technically meet today).

Trust me, dumbshit... everyone in this thread is a prick.