Quote:
Originally Posted by bandersen
I think so, but it's under a metal RF shield and hard to get a good look at. Do you think a tuner designed for VHF could go up to UHF frequencies  |
Some sets, particularly Zeniths, had turret tuners with removable channel strips which could be replaced by UHF strips. The latter would be inserted in place of unused VHF channels in a given area. For example, if your area had channels 2, 4, and seven, and a new UHF channel went on the air on channel 52, you could get a UHF strip tuned to that channel, insert it in an unused position in your TV tuner, and presto, you would now have reception of the new station (provided, of course, that you had the proper UHF antenna; in the days of UHF channel strips, this usually meant a good outside antenna, although if you were very close to the transmitter you could get by with a loop or an indoor UHF antenna).
The maximum number of UHF channel strips that could be installed in any TV tuner is theoretically 12, although in most areas that number was somewhat smaller, especially in New York and Los Angeles which already have seven VHF channels. In these cities, a maximum of five UHF strips could be installed in the tuner, in place of unused channels 3, 6, 8, 10 and 12. In most metropolitan areas, however, there are far fewer VHF stations, so the number of UHF strips that could be installed in the tuner could be as great as nine or 10, although I doubt if any major US city (with the possible exception of Los Angeles) has anywhere near that many UHF stations. In my area near Cleveland, there are only three VHF stations on channels 3, 5 and 8, which leaves nine unused positions. However, there are (never have been) nearly that many UHF stations in this area; before digital, we had UHF channels 25, 43, 55, and 61. When UHF channel strips were popular, Cleveland only had one such station (PBS, then NET affiliate WVIZ) on channel 25, so only one strip would be required, and in fact the MATV (master antenna TV) distribution system at the local elementary school in my old neighborhood downconverted that station to channel 4, so no strips were required or used in those sets to receive the station; as a matter of fact, our TVs were all RCAs which I don't think could have been used with UHF strips.
I think the idea of using UHF channel strips to receive such stations on unused VHF channel positions was patented by Zenith early on, and could not have been used by RCA or any other TV manufacturer without risking a patent infringement suit--or worse. However, there is a way set owners could set up their turret VHF tuners to receive only the local VHF stations in their area--by removing all strips occupying unused channel positions, leaving only the strips for the active stations in the area. This would allow the viewer to switch from one local station to another without going through unused channels, and would also allow the use of UHF strips in the unused positions. Using my area as an example, grouping channels 3, 5 and eight together would leave nine unused channel positions, in which UHF strips for channels 25, 43 and 61 could be installed (further reducing the number of usused channels to six). This would afford the viewer the convenience (especially when tuning by remote control) of tuning to his or her desired station without having to flip through unused channels 2, 4, 6, 7, 9, 10, 11, 12 and 13, as is possible with today's electronic tuners which have an add/delete option for setting desired vs. undesired channels in a customizable scan list. The unused VHF strips could and should be saved in case the set owner moves to an area with different channels; of course, this would mean getting new UHF strips for the different UHF stations in the new area.
Needless to say, however, this is an outdated method of setting a TV tuner for receiving only the area's active channels in this day and age of electronic tuners. It cannot be used with older sets nowadays anyway, as older sets used with ATSC->NTSC converter boxes require that the VHF tuner be set to channel 3 or 4 and left there, all tuning (and presumably on-off power switching of the TV, not to mention volume control and muting) being done either at the box or via its remote.