Indeed, of my suggestions so far it is among the most realistic. I'm actually surprised there isn't such a channel. It seems like such an obvious idea.
New Du Mont high-resolution picture tube and high picture power give a fuller tone range

I like that Thor, African American movie channel so many great African American movies from the 70s, 80s, 90s, and early 00s.

The African-American Movie Channel

• This could work, there's been a reasonable amount of African-American films over the years.
  The Oprah Channel
• Consisting entirely of repeats of classic episodes of "The Oprah Winfrey Show"
  The Bang Channel
• Gun-related programming (including documentaries, dramas, comedies, etc)
  The LGBT Channel
• Because previous channels with this concept ending up jumping the shark.
  The Happy Ending Channel
  , consisting entirely of films and TV episodes with a happy ending.
  New Du Mont high-resolution picture tube and high picture power give a fuller tone range

CCC

• Cult Comedy Channel
  "Where ratings don't matter"
  Basically where I'd keep Happy Endings going if I had infinite money.

This is 2016. This has been a very boring year for me. Replying to this thread provides some amusement to me. Please, let me continue replying.
1990s Frozen in Time

• A channel dedicated to photos taken during the 1990s, which would be presented in a slideshow accompanied with 1990s music. Sometimes these slideshows would be random, others would be dedicated to a particular theme.
  The Curtain Has been Raised
• Films and TV from 1990s eastern Europe.
  The 1990 Channel
• 1990 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1991 Channel
• 1991 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1992 Channel
• 1992 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1993 Channel
• 1993 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1994 Channel
• 1994 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1995 Channel
• 1995 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1996 Channel
• 1996 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1997 Channel
• 1997 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1998 Channel
• 1998 films, TV movies, TV specials, straight-to-video stuff, etc.
  The 1999 Channel
• 1999 films, TV movies, TV specials, straight-to-video stuff, etc.
  Poof! There Goes Perspiration!

Good idea.
There should also be a channel dedicated to African-American series of the 1970s/1980s.
Poof! There Goes Perspiration!

A channel dedicated to 90s black sitcoms.
I'm Blade brown, the Dopest, illest,hypest brotha, on the block!

Additional ideas:
Those marked with "*" are actually good ideas. The rest are a bit silly, but I might watch them.
The B-Grade Western Channel

• Nothing but b-grade westerns of both film and TV. I realise there is a western channel, but one dedicated to the b-grade ones would be fun.
  The Sword Channel
• TV series and films involving swordsmen.

The Swedish Channel

• Swedish films and TV

The Danish Channel

• Danish films and TV

The Dutch Channel

• Dutch films and TV

The African Channel

• Films and TV from countries in Africa
  The Coca-Cola Channel
• Dedicated to Coca-Cola commercials

The German Channel

• German films and TV

The Thai Channel

• Thailand films and TV
  The Blank Channel
• Dedicated to the various versions of "Match Game", including "The Match Game", "Match Game 7x", "Match Game PM", "Match Game-Hollywood Squares Hour", "Match Game" (early 1990s), "Match Game" (late-1990s), plus international versions ("Blankety Blanks", "Blankety Blank", etc)
  The Awards Ceremony Channel
• It could show classic awards ceremonies, such as old telecasts of the Oscars and the Emmys, plus it could hold new awards ceremonies.

The Classic Documentary Channel

• Dedicated to classic documentaries.

Classic PBS

• Dedicated to classic shows from PBS.
  Poof! There Goes Perspiration!

I realise some of my answers are silly (particularly the "Left" and "Right" channels), but I had an interesting idea for a cable channel. It could be a channel where each day, they roughly recreate the line-up for a particular day in TV history. For example, for one day they might show the programs that were shown on 8 February 1991, while on another day they might show what was shown on 17 November 1986. The shows would be drawn from various mainstream networks/channels. The days used would be chosen largely at random.
If possible, they might show the programs at the time-slot they were originally shown (for example, if a episode originally aired at 8:30PM, the channel would show it at 8:30PM). Since networks do not schedule at every time-slot, syndicated series can also be used. However, showing the shows at the original time-slots might prove too difficult and possibly may not be done.
The real question is what to do about overnight/very-late-night programming. Perhaps they could depart from the premise of the channel and just show old b-grade films, something many channels used to do.
A note: I believe a University has a large number of tapes of newscasts, including those of the 1970s, 1980s and 1990s. These could be used as part of the line-ups.
Also, it might not be possible to do 1950s through mid-1970s days, since so many shows of that era were discarded after broadcast.
As I mentioned before, I'm Australian, but all my ideas are intended for the US. I came across a New York City schedule for 8 January 1979, which suggests a possible line-up which may be used, drawn from all three commercial networks plus syndicated shows:
6:00 to 9:59AM ?? (I don't know which are local and which are network)
10:00AM - "Card Sharks" (thank you, Mark Goodson, for keeping the tapes)
10:30AM - "The Price is Right" (thanks again, Mark)
11:30AM - "Family Fued" (there's Mark again!)
12:00PM - "The Young and the Restless" (yes, the production company kept the tapes for this)
12:30PM - "Password Plus" (Mark!! Again!!)
1:00PM - ?? (no idea if "The Hollywood Squares" and "All My Children" were keeping their tapes by then). A syndicated possibly is "Dinah", since Dinah Shore kept most of her shows.
2:00PM - "Days of our Lives" (I believe this was the first US soap to regularly keep its tapes)
2:30PM - ?? (no idea if "The Guiding Light" or "The Doctors" were keeping their tapes by then)
3:00PM - ?? (I don't know if "Another World" or "General Hospital" were keeping their tapes by then)
4:00PM - "Match Game '79" (yet another game show kept by the great producer Mark Goodson)
4:30PM - ?? (was "The Mike Douglas Show" being kept?)
6:00PM through 7:29PM - ?? (OK, I admit it, I don't know which newscasts were national and which were local. The network telecasts may have been kept by the University, the local newscasts are probably lost)
7:30PM - ?? (there is mention of a "Muppet Show" episode, no idea whether this was a re-run or not. Syndicated fare seems to include "The Hollywood Squares" and "The Newlywed Game", whose archival status I don't know)
8:00PM - "Little House on the Prairie"
9:00PM - TV movie: Amateur Night at the Dixie Bar and Grill
11:00PM - ?? (syndicated fare may include "The Gong Show", which I assume was kept)
11:30PM - "The Tonight Show" (I know Carson kept the tapes starting in the early 1970s, so I expect this still exists)
Doing a 1979 schedule is tough, but 1980s and 1990s should be easier with the phasing-out of tape wiping (wiping of network daytime shows, I believe, had been phased out largely by 1980 and completely by mid-1985) and the introduction of cable channels and more syndicated series (which could be used to fill-in gaps when needed)
Poof! There Goes Perspiration!

80s and 90s porn channel.haha. I had watched an old 80s porn at my friend house one time and it was interesting. Today porn films seem so fake its hard to watch all that damn screaming is not necessary.

How about the following:
The 1980s/1990s Porn Channel

• Exactly
  The French Channel
• French films and television
  The Dog Channel
• Videos of dogs. There actually was such a channel years ago.
  .and of course:
  The Miscellaneous Channel
  , for miscellaneous programming of the 20th century
  .and best of all:
  The Really Rare Film Channel
• For really rare films, particularly those that aren't on DVD/Blu-ray, aren't on streaming services, and haven't even been shown on TCM and such.
  EDIT:
  How about
  The Unsold Pilot Channel
  , for TV show pilots that didn't get picked up as a series.
  This is the DuMont Television Network

The Britcom Channel

• Dedicated to britcoms.
  The Lesson Channel
• Educational lessons for the home viewer.
  The Jeopardy! Channel
• Dedicated to repeating episodes of Jeopardy!
  The Wheel of Fortune Channel
  aka
  Wheel of Channel
• Dedicated to showing the various versions of "Wheel of Fortune" produced worldwide.
  Channel
• A channel without a theme. How original..
  The
  Real
  History Channel
• Sorta like the History channel, except actually about history.
  The Wicca Channel
• Like the Shinto people, Wicca people don't seem to have their own channel. This must be corrected.
  The Australian Channel
• Dedicated to showing shows from Australia.
  The Canadian Channel
• Dedicated to showing shows from Canada.
  The Cartoon Channel
• What Cartoon Network used to be.
  The Deluxe Channel
• Dedicated to showing things filmed in Colour by Deluxe.
  The Soviet Channel
• Dedicated to showing films and TV from the former Soviet Union.
  The Monarchist Channel
• Dedicated to showing films and TV about royalty (ranging from cartoons to films and such).
  The Left Channel
• Channel with left-wing content and OPEN about it.
  The Right Channel
• Channel with right-wing content and OPEN about it.
  The sad thing is, of the many channels I've suggested, I'd actually watch nearly all of them. The exceptions are "TV on Shuffle", "The Wicca Channel" and the Left and Right channels.
  ]That's like keeping the smog and throwing away Los Angeles

the ONLY channel I would create would be for Disney and Nick 90's cartoons and shows. I know "The 90's Are All That" is all we have right now, but I would at least change the lineup every few months. geez
I
my Walla
(happipuppi13)

The Opera Channel - Dedicated to showing TV and film versions of operas. They would be "daring" enough to show adaptations that have not been available for viewing for some time (such as
The Devil Take Her (1962)
)
The Anthology Channel - Nothing but anthology series
The Classic Talk Show Channel - Dedicated to classic talk shows of 1950s-1990s. I bet many of them are historically interesting now.
The Gameplay Channel - Walkthroughs, playthroughs, etc of video games.
The Classic News Channel - Dedicated to showing classic newscasts, newsreels, etc.
Any thoughts on these formats?
You're not getting any thinner, this time you're a cookie winner

I like. That would be great and don't forget Carmen San Diego.

Not sure on the name, but I would have want it to be similar to the Hub Network before they changed it to Discovery Family. It have programs that people probably haven't seen in AGES.
Perfect Strangers
Captain Planet
The Huggabug Club
Bananas in Pajamas
Lambchop
Princess Gwenevere and the Jewel Riders
Taz-Mania
Sailor Moon
CBS Storybreak
David the Gnome
The Littles
Eureeka's Castle
The Muppet babies
Richard Scary
Gumby
Inspector Gadget
Bobby's World
Tailspin
Darkwing Duck
Ducktales
Bonkers
Step by Step
Blossom
Chip n Dale: Rescue Rangers
Josie and The Pussycats
Jabberjaw
Speed Racer
Alvin and the Chipmunks
Garfield and friends
Speed Buggy
The Puzzle Place
You dodge a question like a character dodges a punch on Mortal Kombat.-IceJJFish

The Mechanical TV Channel - A recreation of mechanical television of the 1930s.
The Car Crusher Channel - Nothing but videos of cars being crushed.
The 8-Bit Graphics Channel - Colourful graphics generated by 8-bit computers, combined with 8-bit music
The Nintendo Channel - An entire channel dedicated to Nintendo
The Video-Tape Channel - Dedicated to 1950s-1980s programming that was shot on video-tape
The Price is Right Channel - Dedicated to repeating episodes of "The Price is Right". They've certainly made enough episodes of it to do a channel of it.
The Radio Channel - Dedicated to "showing" old time radio shows, combined with various interesting (but not distracting) visuals
The Popcorn Channel - Videos of popcorn popping.
You're not getting any thinner, this time you're a cookie winner

A 24/7 video game channel. Kind of like TechTV that doesn't turn into G4.
A music video channel. I don't know if anyone has tried that yet
A Billy Mays channel, featuring nothing but Billy Mays infomercials.
An "anti-reality" network, that has a smart self-destruct mechanism programmed into the studio and offices should some lazy executive decide to air a reality show on it.
An anti-channel hooked up to random TVs across the world which shows the living room or bedroom of the viewers for a short period of time. The technology would be embedded into future TVs (for all we know it already is.) The channel that watches you! (aka NSA)
A channel dedicated to football 24/7 year round Oh wait, I think they already have one called ESPN.
A non-premium movie channel with continuous play of movies. Play the movies in letterbox and have muted, non-distracting ads on the top and bottom when needed.

After watching old Eastenders clips on youtube I'd like to see an Eastenders channel where they show it from the start

No not at all your list was pretty good. Great but different.

DuMont Television Network II

• A channel which recreates the 1950s TV experience, with 1950s shows of all genres, and featuring only 1950s commercials. I can dream, can't I?
  The Home Movie Channel
• Dedicated to homes movies from 1930s/1940s/1950s/1960s/1970s that were shot on film. I'm probably the only person who would watch this.
  The 1980s Music Video Channel
• Give the people what they want!
  The Cloud Channel
• Videos of clouds in the sky. I'm probably the only person who would watch this.
  The Channel Channel
• A channel which informs us of what to watch on other channels.
  The Ninja Channel
• Bring back ninja services, and give those cuddly assassins their own channel. I'd watch it.
  The Live Channel
  . A channel for which all the shows are aired live, including the comedies, dramas, game shows, kids shows, etc.
  The Oops Channel
• A channel dedicated to showing bloopers, outtakes, deleted scenes, etc.
  I hope these aren't the worst TV channel ideas everI admit some of them are a bit odd.
  I want a signature involving brave swordsmen, kinescopes, and soft drinks

I heard that Lifetime Movie Network doesn't show much in the way of films anymorebut I've already mentioned, I'm not American, I'm just someone very interested in American TV, so I wouldn't know for sure what the channel shows.
I want a signature involving brave swordsmen, kinescopes, and soft drinks

There is an LMN netowrklol.

Lifetime movie network LMN. Only movies all day. All the movies that play during the day would replay over night. So everyone gets a chance to watch. When the am comes again different movies would play. 80's, 90's and now a years. It would be great