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#1
Old 01-30-2000, 10:42 PM
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why did they reserve channel 3 for vcrs?
also, why is there no channel 1 or 0 (at least on my tv)

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#2
Old 01-30-2000, 10:51 PM
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I don't know the exact answer, but when you purchase a CD player that uses an FM frequency (FM modulator,) the signal must be set on a specific frequency that is rarely used. I can't remember but it was 89.9 or something like that.

Using this as an example, channels 3 and 4 are rarely used in analog transmission. Video games use the same channels, at least my Super Nintendo does...haven't gotten around to buying anything other than that, 'sides I like my Donkey Kong Country.

It may not be right, but it makes sense to me
#3
Old 01-30-2000, 11:00 PM
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Because. Probably exactly that reason, or the reason techchick stated. Except I seem to recall that the networks use those channels.

It's probably just a randomly chosen industry standard. Sometimes channel 3 is ABC, but it can also be your VCR.

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#4
Old 01-30-2000, 11:01 PM
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I'm not sure why accessories use channel 3, but The Big Buy covered the lack of channel 1. Check https://academicpursuits.us/classics/a1_372.html
#5
Old 01-30-2000, 11:51 PM
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Actually, channel 4 is very common. Major markets such as New York (WNBC) and Washington DC (WRC) use channel 4. (And I am almost sure KNBC in Los Angeles, too...)

But channel 3 is very uncommon. And wether by design or chance, no market seems to have both channel 3 and 4 at the same time. So most VCRs are set by default to "broadcast" to the TV on channel 3, but most also have a little switch that allows you to use channel 4 if your area happens to have a TV station using 3.

Cecil covered the Channel 1 situation in the first SD book, and the link's above.

- Rick
#6
Old 01-30-2000, 11:51 PM
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Quote:
Originally posted by Saltire:
I'm not sure why accessories use channel 3, but The Big Buy covered the lack of channel[/URL]
Big Buy? Did you mean Big Boy?
#7
Old 01-31-2000, 12:47 AM
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You can't have both a channel 3 and a channel 4 broadcast in the same area. The FCC assigned them frequencies that would interfere with each other.

The maximium number of VHF channels that can be broadcast into one city is 7, and I believe they have to be channels 2, 4, 5, 7, 9, 11, and 13.

I don't know if this will change once all the frequencies get changed around because of HDTV.
#8
Old 01-31-2000, 03:10 AM
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Bob is correct. You shouldn't find a channel 3 and 4 next to each other. That's why your VCR has a choice. Pick the one that ain't on the air.
Your VHF TV frequencies are divided between Channels 2 and 6 (55.25 Mhz to 87.76 Mhz) and Channels 7 to 13 (175.25 Mhz to 215.75 Mhz).
#9
Old 01-31-2000, 03:16 AM
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Whoops! And Bob is not correct about what channels show up in one market.
The channels were assigned by the FCC.
They vary by market.
#10
Old 01-31-2000, 03:54 AM
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Now, wait a minute. Say I live in Fairfield, CA.US. This town has no TV stations itself but KRON, San Francisco (about 50 mi SW), is on Channel 4 and KCRA-TV, Sacramento (about 40 mi NE) is on Channel 3. True they're both NBC, but if you live halfway in between, you may want to watch local programs on both channels. Of course, you may not wish to here about all the crimes in both of these cities and choose to watch neither.

Only techies know how to reach Channel 0. You have to hack to get there, but zero's always a good place to start.

Ray (0 ventured, 0 gained.)
#11
Old 01-31-2000, 06:30 AM
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It's my understanding that the FCC assigns channels in a regional manner designed to minimize interference. That's why Philadelphia uses channel 3, 6, and 10 and New York uses channel 4, etc. - if both cities broadcasted on channel 4, lots of folks halfway between the two cities wouldn't be able to receive either version.

I seem to remember that my VCRs are all programmable to use either channel 3 or channel 4 (your choice). It's been a long time since I've had to set up one, but they're both currently using channel 4 (I'm in the Philadelphia area, and channel 3 on my VCR would potentially suffer from interference by the local broadcasters).
#12
Old 01-31-2000, 11:01 AM
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Cuz no one was using chan 3 or 4 for much when vcrs came out. Same with the old video game systems.

Does anyone remember the old color tv ads? You would have a black & white tv, they would show ads for color tvs & tell you just how nice the color was & you couldn't see it cause you have b/w.

Kinda like that today with HDTV. You can't see how nice it really looks.
#13
Old 01-31-2000, 11:10 AM
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No, I meant Big Guy. Sorry, Cece.
#14
Old 01-31-2000, 01:07 PM
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No one else has mentioned it, so I'll take an educated guess and add that the reason they chose 3 or 4 was that the lower channel numbers use lower frequencies and that made the RF modulators in VCRs & games a little cheaper to mass produce.
#15
Old 01-31-2000, 01:15 PM
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A related question, why do TV manufacturers advertise cable ready TVs with 'X' number of channels (recently I heard about a 256 digital channel cable ready set)? Since most cable companies with more than about 50 or 60 channels in their service require a converter box that outputs on channel 3 or 4. Seems to me that a better definition of a cable ready set would be one that has only channels 3 and 4! Even better, drop the tuner altogether to cut the costs of the set and let the cable boxes output composite video and audio (some of them do already).
#16
Old 01-31-2000, 01:41 PM
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Quote:
Originally posted by Doug Bowe:
Whoops! And Bob is not correct about what channels show up in one market.
The channels were assigned by the FCC.
They vary by market.
But has the FCC ever assigned 7 VHF channels to one market that were not in the 2,4,5,7,9,11,13 combo?
#17
Old 01-31-2000, 01:52 PM
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Quote:
Originally posted by NanoByte:
Now, wait a minute. Say I live in Fairfield, CA.US. This town has no TV stations itself but KRON, San Francisco (about 50 mi SW), is on Channel 4 and KCRA-TV, Sacramento (about 40 mi NE) is on Channel 3. True they're both NBC, but if you live halfway in between, you may want to watch local programs on both channels. Of course, you may not wish to here about all the crimes in both of these cities and choose to watch neither.

Ray (0 ventured, 0 gained.)
There are other things to consider than the strict midway point between to stations. First, of course, is going to be the power of the station. Probably the Sacremento station is going to be the more powerful. This may seem counter-intuitive, however the more of a station's viewership is located in a relatively compacted area (like a city) the less power it needs to broadcast to their audience.

Also, many (maybe all?) radio antennas send out a shaped signal, so that it can reach farther in some directions than others. I assume TV antennas do this as well. This is so you can use your signal more efficiently, by targetting areas with more population or businesses. I don't know if this applies in this case, but it's a possibility.

Checking KRON's and KCRA's website seems to support this. KCRA markets themselves as servicing all of northern Califonia. KRON, OTOH, markets strictly to San Francisco. So, if you live halfway between, more or less, KCRA is probably going to be your NBC affiliate.
#18
Old 01-31-2000, 04:39 PM
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Quote:
Originally posted by BobT:
But has the FCC ever assigned 7 VHF channels to one market that were not in the 2,4,5,7,9,11,13 combo?
Have seven VHF channels ever been assigned to one market at all ?
#19
Old 01-31-2000, 06:00 PM
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Los Angeles has those seven channels and I am pretty sure New York does as well.

Los Angeles didn't give any of its VHF channels to PBS however.
2-CBS
4-NBC
5-WB
7-ABC
9-Independent
11-FOX
13-UPN

The Channel 3 in Southern California is KEYT, which is an ABC affiliate in Santa Barbara.

I would assume that New York and Chicago would have 7 VHF stations in their market.
#20
Old 01-31-2000, 06:08 PM
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New Yorks VHF channel lineup:

2: CBS
4: NBC
5: Fox
7: ABC
11: WB

And two more that might have been part of the same channel assignment (I dont know either way):

9: UPN (Secaucus, New Jersey, which is about 5 miles off the tip of lower Manhattan, even with Staten Island)

13: PBS (Newark, NJ, about 10 miles off Staten Island)


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#21
Old 01-31-2000, 07:34 PM
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"A related question, why do TV manufacturers advertise cable ready TVs with 'X' number
of channels (recently I heard about a 256 digital channel cable ready set)? Since most
cable companies with more than about 50 or 60 channels in their service require a
converter box that outputs on channel 3 or 4. Seems to me that a better definition of a
cable ready set would be one that has only channels 3 and 4! Even better, drop the
tuner altogether to cut the costs of the set and let the cable boxes output composite
video and audio (some of them do already)."

-------------------------------------------
Not everyone wants to pay the extra five bucks for the converter. I've got TeeVees all over the house, but only one converter. I can get all but four channels (two premium channels and the "In Demand" four-dollar per view local movie channels). I just use the converter for an old (ancient) set in the basement with the old clunker-style tuner. If I had to rent converters for three or four more sets, I would buy satellite. Better quality, but much more expensive, and my eyes can't tell the difference from accross the room anyway.

That, and multi-channel tuners are fairly cheap to produce. It wouldn't take much off the price of the set to not have one, and to not have a cable-ready tuner would make your product singularly brain damaged when compared to other products.

The answer to the last question is because composite video and audio is not very good. It does not do much good, as an example, to sell a digital cable product with fantastic resolution and sound and make it look and sound as bad as an analog broadcast signal by piping it through the composite RF connection.
#22
Old 01-31-2000, 08:34 PM
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The New York stations would all be considered the same market.
To be precise, not all of the LA stations are in Los Angeles, the NBC affiliate is in Burbank.
The other six stations are in Los Angeles.

I am pretty sure that all the transmitters are on Mount Wilson (which isn't in any city)
#23
Old 01-31-2000, 08:46 PM
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Actually channel assignment is more political than anything.

Technically you could have 2,4,6,7,9,11,&13. That would be 7 stations.

But if you look at markets like Tampa they should not have ch 10. Miami had it. So they made it a short 10. Less power.

We got a low power 23 in Chgo. But its trans is on the Sears Tower so it reaches better than our full power 62.
#24
Old 02-01-2000, 12:46 AM
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Facts.

Not all channels that seem to be adjacent actually are. Some have non-television uses in between.

When VHF channels were assigned in the 1930's, truly adjacent channels were never assigned to the same city, to prevent interference. Because of that, 3 and 4, in particular, are never in the same city, and, therefore, most VCR's, videogames, etc., use them (with a switch to decide which of the two).

Modern televisions don't have a problem with adjacent channels, anyway, so cable uses them all.

4 is quite common; historically, it was the channel for NBC in major cities.

3 is less common, because it was assigned to second-rank cities.

A Channel 1 was assigned in the original 30's scheme, but in the 40's it was withdrawn for use by the military.

ABC heard a rumor that the military was going to take Channels 1-6, and ran around buying the rights to 7 and 8 wherever possible. 7-13 are in a different region of VHF that isn't as good as 1-6, but they figured that they'd end up first on the dial. When only Channel 1 was taken, ABC was left holding the bag, which is why, from the 50's to the 70's, ABC was the network that took the most chances -- they had to catch up.

A Channel 1 and a Channel 0 are to be found on some cable systems, but they are usually scrambled and unadvertised. I suspect they may be hotel services, or something of the sort. I don't know whether this Channel 1 is the same as the old Channel 1.

All the other VHF channels (14 and up) are in regions of the spectrum that are used for non-television applications in broadcast, but are perfectly free in cable. They are not the same as the UHF channels 14 and up. (A cable that's good for carrying VHF has different characteristics from a cable that's good for carrying UHF.) That's why they used to call them Channels A, B, C..., but after they got to Z, they decided to junk that idea and simply number them, despite the confusion with UHF.

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#25
Old 02-01-2000, 07:49 AM
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Hmmm.... I just noticed my cable is fed through channel 3 too. What's funny is I'm forced to use two remote controls, one for volume, and one for selecting the individual cable channels from my cable box...
#26
Old 02-01-2000, 08:38 AM
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tbea925 writes:

Quote:
Not everyone wants to pay the extra five bucks for the converter. I've got TeeVees all over the house, but only one converter.
This only works with some cable services and even then only for the next few years. Due to the government mandated conversion of broadcasts to digital, by 2005 there will be no analog signals to be had (probably earlier in some areas). All TVs that are not "digital-ready" will require a converter box.


Quote:
That, and multi-channel tuners are fairly cheap to produce. It wouldn't take much off the price of the set to not have one, and to not have a cable-ready tuner would make your product singularly brain damaged when compared to other products.
I agree with your first statement, they'd be cheaper to produce. I sort of agree with your second statement, though not for the reasons you state. The current "intrinsic value" that retailers attach to channels is about a dollar per channel. In other words, two TVs with identical features except that one tuner supports 50 channels more than the other will cost the consumer about $50 more. The problem is that 95% of this is pure margin. Manufacturers and retailers would never just give that margin away, so if TVs were made available with no tuners, they would find some other "feature" to charge consumers with. As to your third statement, I'd buy a TV that had only channels 3 and 4 if it meant that the cost of the set were $150 cheaper, but as I said that would never happen... so, like some consumer technology cold war the number of cable channels continues to escalate...


Quote:
The answer to the last question is because composite video and audio is not very good. It does not do much good, as an example, to sell a digital cable product with fantastic resolution and sound and make it look and sound as bad as an analog broadcast signal by piping it through the composite RF connection.
First, composite video is not RF. Second, I think you're confusing digital broadcast with high definition. The fact that the incomming broadcast is digital has nothing to do with the display characteristics. You might have an argument that you can't use composite video with high definition TV due to bandwidth limitations... but, that's not valid either because there are composite video standards that can handle the extra bandwidth required to support HDTV. In fact, most HDTV equipment have multiple composite video inputs and outputs... why? Because you first statement in the last paragraph is completely bass-ackwards. Composite video is much higher fidelity than the coax that runs between your VCR and TV or your cable box and TV.
#27
Old 02-02-2000, 01:19 PM
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Originally, NYC had 2, 4, 5, 7, 9, and 11, and Newark had 13. But the Newark station was a money loser, and in the early 60's the FCC eventually allowed it to be sold to New York and NET (ancestor, more or less, of PBS). That left the entire state of NJ with no VHF station, which produced quite a few complaints.

Some years back, the parent company of Channel 9 got caught doing something they shouldn't, and as "punishment" they were forced to move their offices to Secaucus, a completely undistinguished town just barely over the state line. Of course, as soon as they did, the FCC pretty much forgot the whole New Jersey issue, and it was back to business as usual for most purposes. The UHF PBS stations of New Jersey Network continue to be the only real New Jersey stations.

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#28
Old 02-04-2000, 04:05 PM
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Just wondering, what did WOR-9 do back then to be met with such a fate?
#29
Old 02-07-2000, 06:28 PM
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It wasn't WOR (WWOR now) itself, but its then owner, a tire manufacturer. I couldn't recall the details when I made the earlier post, and I still can't. Some sort of accounting no-no, I think.

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#30
Old 02-08-2000, 01:47 PM
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I hate to beat this topic any more to death, but I just found this out last night from one of my son's Boy Scout merit badge books.

As has been noted, not all TV channels are next to each other, even though their numbers are. And in fact, there is a little gap in frequency between Channels 3 and 4. As a result the spectrum looks like this.

2-3, 4-5-6, (and then a big gap) 7-13.

As a result, it makes sense to have a VCR, videogame or whatever switch between 3 and 4, because -- compared to the other channel pairs -- there will be less chance it would interfere with the TV station next to it.

The little break in frequency also allowed the FCC to offset channels 4 and 5 (4 would transmit a little below its center frequency, and 5 a little above) which is why in xome cities you'll see both Channel 4 and 5, but never any other two adjacent channels.

As for why the equipment isn't set on the high-band (7-13) VHF, my guess would be that because during the early days of TV, the high band was considered harder to work with, and they tried to do as much in the lower frequencies as possible. And that's how industry standards are born.

Have we moved into MPSIMS yet?
#31
Old 02-08-2000, 03:37 PM
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Quote:
Originally posted by BobT:
But has the FCC ever assigned 7 VHF channels to one market that were not in the 2,4,5,7,9,11,13 combo?
From the olden days when I lived in Dallas before cable arrived:

2--became KDTN-PBS
4--KDFW-CBS
5--KXAS-NBC
8--WFAA-ABC
11--KXTX (Independent)
13--KERA-PBS

Of course, it's changed since then. But it breaks your pattern: 8 instead of 7 and 9. Lo siento mucho!
#32
Old 02-08-2000, 03:39 PM
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Sure, that's only six stations (now that I'm counting), but still...
#33
Old 02-08-2000, 04:13 PM
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So why was it verboten to assign different stations to channels 3 and 4 in the same area, but perfectly OK to assign different stations to channels 4 and 5 in the same area?
#34
Old 02-09-2000, 12:35 AM
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Hey Handy! Congrats on your 3000 post!
I'll be there someday...
#35
Old 02-09-2000, 06:56 PM
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Because the channels are not all really adjacent. That's one reason that 99% of televisions have, unlike radios, always used discontinuous tuning controls. There is a gap between 4 and 5 and a big gap between 6 and 7 (FM radio lives there, along with several other things). There may be other gaps, too; I'm not an expert.

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#36
Old 02-10-2000, 08:34 AM
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I feel a little quantification is in order...

From my ever-so-handy Handbook of Electronic Tables & Formulas, 5th edition, 1979: (It's an oldie but a goodie!)

key:
P = picture carrier frequency (MHz)
S = sound carrier frequency (MHz)

Ch. 2 P = 55.25, S = 59.75
Ch. 3 P = 61.25, S = 65.75
Ch. 4 P = 67.25, S = 71.75

(here's the first significant gap)

Ch. 5 P = 77.25, S = 81.75
Ch. 6 P = 83.25, S = 87.75

(here's the second significant gap; note that it includes 89 MHz to 107 MHz, the FM radio band. It also includes the 2-meter ham radio band, 144-148 MHz)

Ch. 7 P = 175.25, S = 179.25
Ch. 8 P = 181.25, S = 185.75

...and so on, somewhat continuously (I'm getting bored with typing these things), 'till...

Ch. 13 P = 211.25, S = 215.75

And here's the big gap between VHF, very high frequency (30-300 MHz), and UHF, ultra-high frequency (300-3000 MHz).

Ch. 14 P = 471.25, S = 475.75.

Enjoy!

Pantellerite
#37
Old 02-10-2000, 02:29 PM
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So what lives in the ~4 MHz gap between channel 4 and channel 5?
#38
Old 02-10-2000, 02:34 PM
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Quote:
Originally posted by tracer:
So what lives in the ~4 MHz gap between channel 4 and channel 5?
hmmm, sounds like a government conspiracy to me!


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