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Old 01-09-2012, 11:31 PM
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Jeffhs Jeffhs is offline
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Join Date: Feb 2003
Location: Fairport Harbor, Ohio (near Lake Erie)
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Quote:
Originally Posted by ha1156w View Post
I'm puzzled. I had always understood 83-channel sets were sold up until the 1990's to make room for analog cellular phones. One could occasionally pick up a single side of the analog phone calls on old sets (being two-channel duplex). I don't recall seeing my first 2-69 set until well after knob-tuned sets were phased out. What was the initial changeover to 2-69?
That was one reason channels 70 through 83 were eliminated on UHF TV tuners starting about 1990 or so -- the FCC did not want people listening in on cordless telephone calls. However, today's cordless phones, operating in the GHz (gigahertz) range, cannot be easily eavesdropped on since the actual frequencies within these bands on which the phones actually operate is never disclosed -- in the instruction manual or elsewhere. The same reasoning applies to cellular telephones, although, since these phones are mostly used by non-technical people, the frequencies or frequency bands on which the phones operate are never mentioned anywhere in the manual or even on the phone itself. Most people having and using cell phones, after all, could not care less how or over what frequencies their calls are transmitted; as long as the phone makes and receives calls, that's all they care about.

My Zenith Sentry 2 and also my RCA CTC185 color TVs have UHF tuners that stop at channel 69, not that any of this matters anymore with digital TV transmission. The UHF television band was butchered badly by the time DTV arrived; first the UHF band was channels 14-83 (1950s until 1970), then channels 70-83 were eliminated (1970s-late 1990s), and now, late '90s to today, the current UHF TV broadcast band, channels 14 to 55 or something like that. Since analog cable TV service is to be phased out by most cable operators in the not-too-distant future (and has been phased out in many areas already, even as I write this), it would not surprise me if even that range of channels is eventually reassigned to other services. Do not forget that the rationale behind switching TV from NTSC analog to ATSC digital, spectrum auctions, et al. was to clear the old analog TV channels so they can be utilized by other services.

I'm surprised you saw your first TV without channels 70-83 long after analog-tuned TVs were phased out. The only thing I can think of is that you must have seen a few older knob-tuned sets with detent UHF and VHF tuners that were being sold at dirt-cheap prices, just to clear out the store's old inventory. I forget the date, but some time in 2007 a law was enacted that made it illegal to sell new TVs with old-style knob tuning; this is why the stores sold these TVs, however many or few they may or may not have had left in their stocks, at such deep discounts. The ruling did not then and does not now apply, however, to used TVs sold on eBay, Craigslist, or other online auction sites, or through private sales (yard, garage, rummage sales, etc).
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Collecting, restoring and enjoying vintage Zenith radios since 2002

Zenith. Gone, but not forgotten.
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