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  #16  
Old 02-11-2012, 09:45 AM
W3XWT W3XWT is offline
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That Jerrold box you're thinking of was likely the "JSX". with a three position switch on the left and a fine-tuning control on the right. Jerry also had a "remote" version called the "JRX".

Talk about crap! They were among the prototypes!!!




Quote:
Originally Posted by radiotvnut View Post
Somewhere around here, I have one of those old late '70's-early '80's Jerrold cable boxes with a row of mechanical click-style buttons for channel changing. I think those boxes would go to channel 37 and I don't recall actually seeing one in use since around '86. Since then, most people had the digital readout boxes that would turn the TV on and off, as well as change channels with the remote. Some of the fancier boxes would even control the volume.
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  #17  
Old 02-11-2012, 11:45 AM
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That's the one.

I also remember seeing some cable boxes that had a single mechanical knob tuner, similar to the single knob varactor tuners in some TV's.

IIRC, that Jerrold box had dirty switches in it when I got it. It worked OK after I cleaned; but, of course, it's now only good for a paperweight, since everything above channel 12 is digital.
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  #18  
Old 02-11-2012, 12:12 PM
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There was discussion at a convention for cable system owners/operators that they needed to drop analog.

With increasing pressure from all digital systems, as well as additional space needed for more internet and HD...analog cable is going the way of analog OTA.

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  #19  
Old 02-11-2012, 01:43 PM
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Think I got one of those non remote Jerold cable boxes stashed away somewhere. If it went a bit higher I'd use it on one of my vintage sets.
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  #20  
Old 02-11-2012, 01:59 PM
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Quote:
Originally Posted by radiotvnut View Post
That's the one.

I also remember seeing some cable boxes that had a single mechanical knob tuner, similar to the single knob varactor tuners in some TV's.

IIRC, that Jerrold box had dirty switches in it when I got it. It worked OK after I cleaned; but, of course, it's now only good for a paperweight, since everything above channel 12 is digital.
I live in Lake County, Ohio. When cable arrived here in 1982, we had Jerrold converter boxes for our TVs like the one being described (one for the living room set and another for my Zenith 13" color portable in my bedroom). The cable in our area at the time only carried something on the order of 40 channels, all analog. Today, such boxes are obsolete several times over (as radiotvnut and anyone else trying to use analog cable boxes has discovered), since of course they do not work with digital TV.

Edit: I did not realize Jerrold also made a remote-control version of this box. Would have been nice if they had kept it around awhile, updated of course for DTV. I wonder how difficult it would have been to update the JSX/JRX versions for digital TV. Would it have been a major job to upgrade these boxes, or did Jerrold just give up on this series when DTV arrived?
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Last edited by Jeffhs; 02-12-2012 at 01:21 PM.
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  #21  
Old 02-17-2012, 07:00 PM
NJRoadfan NJRoadfan is offline
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One of these classic boxes?



Gotta love that simulated wood grain finish.

For those expecting a large lineup using a QAM tuner, good luck. Most cable systems have encrypted everything except for the OTA stations, which federal law requires to be transmitted in the clear.
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  #22  
Old 02-17-2012, 07:15 PM
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My box is similar, but the wood grain top extends farther back form the controls and the grain is darker though.
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  #23  
Old 02-18-2012, 11:38 AM
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Something else I wonder is how long will the cable companies provide boxes that output an NTSC RF signal on channel 3/4?
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  #24  
Old 02-18-2012, 01:22 PM
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Quote:
Originally Posted by radiotvnut View Post
Something else I wonder is how long will the cable companies provide boxes that output an NTSC RF signal on channel 3/4?

Probably as long as there are older NTSC CRT TVs. Once these old sets are completely out of service and have been replaced by flat panels (that day is coming, if it hasn't arrived already), the need for cable boxes will disappear, as will the boxes themselves. Eventually, the only uses for the old-style boxes that convert digital ATSC to analog NTSC will be as tuners for very old NTSC CRT sets such as are owned by VK members in their collections, or as paperweights.

Bear in mind, however, that many if not most or all of the older ATSC->NTSC cable boxes, removed from cable company service, may not and likely will not work as-is because these boxes must be activated with a special code to which only the cable company's technicians have access. Once boxes are removed from service, they may well be permanently locked so that they cannot be used for free cable service. There may be an FCC rule which requires cable operators to disable old, obsolete cable boxes in this way when new ones are phased in.
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  #25  
Old 02-18-2012, 04:30 PM
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I don't see cable boxes going away; rather, I see the NTSC RF output connector going away from future boxes. As long as the cable company is sending out it's signal as "non-clear", there will be a need for some sort of decoder between the cable line and the TV.

And, yes, the current digital cable boxes must be activated. When we got our boxes and connected them, there was a message on the screen with instructions to call a phone number. When the number was called, I was directed to an automated system (no surprise). After entering the serial numbers of the boxes and after the system pulled up my account, a signal was sent down the line to activate the boxes and enable them to receive the level of service that I was paying for. I suspect the new way of doing it will prevent a lot of cable theft. In the old days, a crook could climb the pole, connect his cable, and he was in business (until they caught up with him). Back then, cable boxes could be purchased at many electronics stores and they required no sort of activation.

The way they used to prevent viewing of certain channels was to install a trap in the line. Many times, I've heard of people bypassing the trap and were able to watch the premium channels. Someone told me that they were once able to watch a PPV movie by fine tuning one TV to receive the sound and fine tuning another TV to view the picture. I've also heard of people, back in the early days of cable, wrapping a piece of aluminum foil around the cable and sliding the foil up and down the cable in order to receive HBO. At one point, I remember some of the premium channels could be clearly heard; but, the picture would be scrambled. IIRC, HBO was the only premium channel in my area that had both the picture and sound scrambled.

Back in the late '80's, someone was bragging to me about how he climbed the pole in the middle of the night, connected his cable, managed to get an "under the table" cable descrambler box, and was able to watch everything the cable company offered (for free). I warned him that they'd eventually catch up to him; and, they did. After that, I think he realized that he should have just gone ahead and paid for the service.
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  #26  
Old 02-21-2012, 11:50 AM
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Quote:
Originally Posted by radiotvnut View Post
I don't see cable boxes going away; rather, I see the NTSC RF output connector going away from future boxes. As long as the cable company is sending out it's signal as "non-clear", there will be a need for some sort of decoder between the cable line and the TV.
What exactly is the difference between clear and non-clear QAM cable TV signals? My flat-screen TV gets 50 digital cable channels and 64 analog ones without a cable box; I guess the 50 digital channels I'm getting must be clear QAM.

BTW, if tomorrow's cable boxes will be made without RF output ports to connect to the antenna input of the television, how on earth would one connect such a box to the set, or would the box be physically connected to the television at all? I'm thinking that if the RF connector is done away with, the box will get its signal input either wirelessly or through a hard-wired Internet connection, but that still leaves the question of how the box would connect to the TV. I am not presently aware of any way to wirelessly connect a television set to today's cable or satellite services, particularly the former.
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  #27  
Old 02-21-2012, 01:00 PM
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Quote:
Originally Posted by Jeffhs View Post
What exactly is the difference between clear and non-clear QAM cable TV signals? My flat-screen TV gets 50 digital cable channels and 64 analog ones without a cable box; I guess the 50 digital channels I'm getting must be clear QAM.
YES! the 50 or so digital channels that you are seeing are indeed "clear QAM" ... the hundreds of digital channels that you are not seeing are "scrambled QAM". This Wikipedia quote perhaps explains it better than I can:

Quote:
In North American digital video, a QAM tuner is a device present in some digital televisions and similar devices which enables direct reception of digital cable channels without the use of a set-top box. An integrated QAM tuner allows the free reception of unscrambled digital programming sent "in the clear" by cable providers, usually local broadcast stations, cable radio channels, or in the case of providers which have transitioned to do so, Public-access television cable TV channels. Which channels are scrambled varies greatly from location to location and can change over time; the majority of digital channels are scrambled because the providers consider them to be extra-cost options and not part of the "basic cable" package.
http://en.wikipedia.org/wiki/QAM_%28television%29

BTW, In general QAM is the only modulation scheme used on cable for digital channels (scrambled or not) ... ATSC is used for Over The Air transmission. ATSC is more robust for OTA, while QAM allows more channels in a given bandwidth, which cable providers like.

Quote:
Originally Posted by Jeffhs View Post
BTW, if tomorrow's cable boxes will be made without RF output ports to connect to the antenna input of the television, how on earth would one connect such a box to the set, or would the box be physically connected to the television at all? I'm thinking that if the RF connector is done away with, the box will get its signal input either wirelessly or through a hard-wired Internet connection, but that still leaves the question of how the box would connect to the TV. I am not presently aware of any way to wirelessly connect a television set to today's cable or satellite services, particularly the former.
Most modern sets have a variety of inputs that provide higher quality viewing than the old fashioned ch3/4 NTSC connection. In order of increasing quality; Composite Video, Component Video and HDMI inputs are usually provided . Check the back of your set... should be lots of inputs.

ADD: WIFI TVs do exist for wireless connection to the internet and other hosts, such as this example:

http://www.amazon.com/VIZIO-XVT323SV...9861357&sr=8-2

Not affiliated,
jr

Last edited by jr_tech; 02-21-2012 at 04:47 PM. Reason: add WIFI TV link
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  #28  
Old 02-21-2012, 09:40 PM
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Something here that may shed some light on the subject...

http://broadcastengineering.com/RF/D...-FCC-02162012/
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  #29  
Old 03-26-2012, 11:29 PM
Dude111 Dude111 is offline
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Quote:
Originally Posted by W3XWT
Just like over-the-air TV, the cable companies face a finite amount of spectrum.
Yes and its a shame they are wasting it on all this new crap!

HDTV,etc.......

I could care less for any of that crap..... All i want is basic STANDARD DEF (And if possible IN ANALOGUE as it looks and sounds MUCH BETTER)
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  #30  
Old 06-10-2012, 07:34 PM
Keefla Keefla is offline
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Quote:
Originally Posted by radiotvnut View Post

Somewhere around here, I have one of those old late '70's-early '80's Jerrold cable boxes with a row of mechanical click-style buttons for channel changing. I think those boxes would go to channel 37 and I don't recall actually seeing one in use since around '86. Since then, most people had the digital readout boxes that would turn the TV on and off, as well as change channels with the remote. Some of the fancier boxes would even control the volume.
I remember this type of cable box from the 80's. my family had one when i was younger, we also had a black box type with a dial click tuner type knob on the front....that one also went to 36 or 37, in my parents room they had a kinda cool box where the 'box' was just an unpainted metal box with the cable in/out and a looooong wire coming out of it going to a beige box with a slide-type selector along the front and fine tuning knob at the end. the channel numbers were listed along the front above the slider and they would illuminate when you positioned the slider behinde them, indicating the channel. these all were from about 84-87 id say. the wire on the one in my parents room was too short for my dad to change the channels from his bed to he spliced in a length of telephone wire to it so it's reach.
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