Metroliner telephone article 4071

Television doesn't use an FM subcarrier for the sound. Many years ago in the days of yore, the sound was carried by an FM sound transmitter that was completely independent of the video transmitter, except for the means of combining signals from the video and aural transmitters into one common antenna. I don't know what today's state of the art might be, I suppose it is possible that both signals might be feed through a common high power amplifier today, although the FM sound carrier still remains a separate enbreasty in NTSC.

I don't know why remote control of Television transmitters wasn't allowed earlier, I suspect that as you say "Remote signal tweaking technology was probably inadequate", although it would be my guess that modern Television transmitters don't depend so much on "Remote signal tweaking technology" as they do on highly stable solid state automatic video controls to maintain the proper video parameters. During my college years in the early 1960's I worked as a transmitter operator. There were a handful of controls on the transmitter control console that adjusted the video modulation and the sync parameters. There was nothing related to the color subcarrier, which mostly depended on the alignment of the transmitter, plus a video processing amplifier that was connected between the incoming video line and the transmitter. The alignment of the transmitter was not something that would be changed casually, whether by remote control or by a man, the transmitter would have to be taken off the air to make any adjustments like that. The video processing amplifier probably did have some adjustments related to color operation, but these were not adjusted on a day to day basis.

I suspect that modern solid state gadgets made it possible to automatically maintain the proper video modulation and sync levels, without manned intervention, allowing the use of remote control to be authorized, but I don't really know if that is the reason or not, it would be interesting to know what changed that allowed remote operation of Television transmitters to be authorized in the US?

Regards,

John Byrns