mikey@trsvax.UUCP (12/27/84)
Does anyone on the net know anything about the proposed format for the networks broadcasting in stereo? The latest info that I got is that NBC has been sporadically broadcasting stereo of the Tonight Show since July 26, and that ABC only broadcast selected cuts of the Olmypics in stereo. I know that PBS is planning on nationwide stereo before the end of 85. I just bought a Beta HiFi. It doesn't make sense to me to go buy a stereo TV receiver. I'm going to run raw video to my TV (after I gut the tuner, which is shot anyway). Since the Beta will always be set to channel 3 output, I want to make a separate decoder box so I can run the stereo signals into the Beta in the simulcast mode and to the audio amplifier for listening. So far I haven't been able to find anything out about the format of the encoding. Most people I've talked to THINK it is either similar to or the same as FM stereo. If not the same, just a different pilot frequency with extended frequency response. Does ANYBODY know? mikey at trsvax
dwl10@amdahl.UUCP (Dave Lowrey) (01/02/85)
> > > > Does anyone on the net know anything about the proposed format for > the networks broadcasting in stereo? The latest info that I got > is that NBC has been sporadically broadcasting stereo of the > Tonight Show since July 26, and that ABC only broadcast selected > cuts of the Olmypics in stereo. I know that PBS is planning on > nationwide stereo before the end of 85. > See the September 84 'Video review' (mine seems to be missing). They have an extensive list of who will make what equiptment, and who will be broadcasting what and when. P.S. While watching VOLTRON, the worst cartoon on TV, with my son one day (it's his favorite), I noticed in the credits that it is in stereo. It's from Japan (of course!). -- ----------------------------------------------------------------------- Dave Lowrey "GORT...Klatu borada niktow" ...(<hplabs,ihnp4,nsc>)!amdahl!dwl10 [ The opinions expressed <may> be those of the author and not necessarily those of his most eminent employer. ]
doug@terak.UUCP (Doug Pardee) (08/09/85)
> They have very little programming in stereo, so I haven't run out the > get the MPX decoder from my local dealer. I haven't run out to buy an MPX-stereo TV either. My cable company doesn't carry the stereo signal, and they aren't planning to. If the pressure for stereo gets high enough, they'll put it on FM (a la MTV), not MPX. I believe nearly all cable companies are doing the same. -- Doug Pardee -- CalComp -- {seismo!noao,decvax!noao,ihnp4}!terak!doug
brown@nicmad.UUCP (08/13/85)
In article <668@terak.UUCP> doug@terak.UUCP (Doug Pardee) writes: >> They have very little programming in stereo, so I haven't run out the >> get the MPX decoder from my local dealer. > >I haven't run out to buy an MPX-stereo TV either. My cable company >doesn't carry the stereo signal, and they aren't planning to. If the >pressure for stereo gets high enough, they'll put it on FM (a la MTV), >not MPX. I believe nearly all cable companies are doing the same. I think I should correct this now before it gets out-of-hand. The correct term for the new stereo TVs is MTS (Multi-channel Televison Sound), not MPX (Multi-PleX). What the first gentleman should have said was that he wasn't going to run out and get a MTS decoder that plugs into his MPX jack. Some TVs, including one of them that I have, have a MPX jack on the back of the set. This is the tap point in the audio circuitry before the FM de-modulator. This is the baseband audio before any decoding takes place. We should all be a little careful on how we describe these things. As a side note, my local cable company doesn't know what they are going to do. One station of four has gone stereo, another one will this fall and a third will next year. Don't know about the fourth yet. Anyway, our local cable company doesn't know if they are going to get MTS transmission encoders and/or go FM stereo. If they go FM stereo, more people will just tap into the cable and hook up the FM for free. Around here it is considered a second set connection. No extra income for expenses. Now, if they go the MTS route, they definately won't get any extra money for the expense. But, when the local stations are all stereo, who would want to get cable when the stereo TVs they own won't get stereo on cable, but will off the air. Time will tell on this one. Oh, the first local station to go stereo is apparently going to help with the cost of putting the MTS signal onto the cable, ie, they are going to MTS encode it at the TV station and ship it back to the cable company all ready to go. All of our local stations are directly connected to the stations, so if the TV transmitter dies, those on cable still get picture and sound. -- |------------| | |-------| o| HRD725U & PV9600 Mr. Video | |AV-2010| o| |--------------| | | | | | |----| o o o | | |-------| O| |--------------| |------------| VHS Hi-Fi (the only way to go) {seismo!uwvax!|!decvax|!ihnp4}!nicmad!brown
hoffman@pitt.UUCP (Bob Hoffman) (08/13/85)
In article <309@nicmad.UUCP> brown@nicmad.UUCP (Mr. Video) writes: >... >Some TVs, including one of them that I have, have a MPX jack on the back >of the set. This is the tap point in the audio circuitry before the FM >de-modulator. This is the baseband audio before any decoding takes place. > >We should all be a little careful on how we describe these things. I agree... we should be careful. Baseband audio is what comes out of an FM demodulator, not what goes into it. And now, a question of my own: What is the modulation scheme used by NBC (RCA) for their stereo broadcasts? -- Bob Hoffman, N3CVL {allegra, bellcore, cadre, idis, psuvax1}!pitt!hoffman Pitt Computer Science hoffman%pitt@csnet-relay
brown@nicmad.UUCP (08/14/85)
In article <1249@pitt.UUCP> hoffman@pitt.UUCP (Bob Hoffman) writes: >In article <309@nicmad.UUCP> brown@nicmad.UUCP (Mr. Video) writes: >>... >>Some TVs, including one of them that I have, have a MPX jack on the back >>of the set. This is the tap point in the audio circuitry before the FM >>de-modulator. This is the baseband audio before any decoding takes place. >> >>We should all be a little careful on how we describe these things. > >I agree... we should be careful. Baseband audio is what comes out of >an FM demodulator, not what goes into it. Yes, but, by definition the information coming out of the MPX jack is still baseband, ie, it does not require further mixing with RF/IF frequencies in order to get what you want. True, you do have to but it thru a de-modulator in order to hear the audio, but no IF frequencies are mixed with it. I know, the 19 KHz is still used, but that is after the demodulation. Think of the MPX output jack being somewhat like the video output of a VCR or TV that is tuned to a cable channel that is scrambled. The video signal is still baseband, but you can't watch it. But, bu doing a 'de-modulation', en-encoding, you can watch it. Yes, I know, most cable converters do it at IF frequencies, but baseband decoders do exist. So, just because we can't hear the information coming out of the MPX jack, it is still baseband information. >And now, a question of my own: >What is the modulation scheme used by NBC (RCA) for their stereo >broadcasts? I am not sure what you are asking. So, I will try and give you a guess. NBC doesn't do the broadcasting. Their affiliate stations do it. I include the stations that they own as affiliates. The program goes from the New York network control room to their contracted satellite uplink site. I talked with our local NBC affiliate engineer and he didn't know what the uplink method was, as NBC provided the satellite receiver. If it goes wrong, NBC fixes it. I suspect that it is the L+R and L-R method, ie, one audio sub-carrier for each of the two audio signals. From there, the local station gets separate L and R audio signals to run thru their sound board and then to the audio transmitter, which has the MTS encoding equipment. So, NBC tapes are L and R, sent to uplink site, encoded for transmission, received by affiliate, broken into L and R, sent the TV audio transmitter, encoded into MTS format. Basically the MTS format is like FM, ie, L+R (mono) and L-R (difference). The added thing is the dbx encoding of the L-R signal and the addition of the SAP (Secondary Audio Program) sub-carrier. I hope this helps. If not, let me know. -- Mr. Video {seismo!uwvax!|!decvax|!ihnp4}!nicmad!brown