Could NTSC VIR = PAL

[NewVista]

Originally Posted by kf4rca

VIR was required till the end of analog transmission. The ONLY set I ever remember that utilized it was a 19 inch GE that was installed at a station I worked at in '77 in SC.
And I remember seeing a Sylvania that used the GCR in the 90's.

That's what I thought, only really seen it on the GE 19" with that red VIR light on controls panel. What a pity as VIR was a brilliant innovation

[Electronic M]

I know someone with a VIR set that has a gassy CRT.

[Kamakiri]

Originally Posted by Electronic M

I know someone with a VIR set that has a gassy CRT.

My parents bought a GE 25" console with VIR new in '77. Lasted until '83. Been looking for a VIR equipped set for many years and never found one.

[Electronic M]

Originally Posted by Kamakiri

My parents bought a GE 25" console with VIR new in '77. Lasted until '83. Been looking for a VIR equipped set for many years and never found one.

His is a 19" GE...I don't know if he would sell it, but I could check.

[kf4rca]

The lack of set manufacturer adoption led many broadcasters to think these signals had another purpose. By putting test signals in the vertical interval, it allowed the FCC to evaluate your transmitters performance that they couldn't do with just program video.
While most VHFs kept the "house" clean, many UHFs were barely staying on the air.
I had heard that some stations were fined for excessive group delay and others recieved warnings.

[lnx64]

Speaking of UHF, I got in an auction, one of the RF modulators used at one of the UHF stations in the area. Among a weird coaxial baseband video input, it also has the emergency broadcast inputs too. And when I got it, it was still set on the frequency that the station aired, it was never messed with.

[lnx64]

So I'm guessing VIR has nothing to do with the auto color button on my TV?

[kf4rca]

They DO run a line of color bars. But one of the biggest problems of NTSC is that it was compromised from the beginning. It had to fit in the same space as the existing B&W system.
As a result the bandwidth of the chrominance was limited. The I components were limited to 1.5 MHz and Q is limited to .5 Mhz. Not much detail in the color. AND its not even symmetrical. How screwey is that???
NOW, in Japan they had an analog HD system called the MUSE which I've heard took a 12 MHz channel. So when color (and HD) came along ,they should have allowed MORE bandwidth than what the old B&W system started out with.
SO, even today we are stuck with the constraints of an old system.

[NewVista]

Originally Posted by kf4rca

They DO run a line of color bars. .

I've seen them sometimes at top of underscanned picture.
So alternatively, this is as good as VIR insomuch as there should be no guesswork for the tech before adding new VIR before transmission, as all he has to do is line up the color bars in the vectorscope avoiding subjectivity.

And since, by 1975, NTSC still had 40 more years (counting cable), LSI chips could have been produced for consumer TVs to either derive reference from V.I. colorbars or VIR and making this the default mode of the receivers - keeping consumers' fingers away from contrast and tint - if not also saturation - knobs!

[dishdude]

Cool early 80's GE projection with vir on ebay.

http://www.ebay.com/itm/Vintage-Anti...sAAOSwHoFXu0Kd

[NewVista]

Originally Posted by dishdude

Cool early 80's GE projection with vir on ebay.

That set has 'VIR II' - wonder what improvements were made by then (1982)?

Magazine article on VIR

[Boobtubeman]

Had a Mot WARDS 19" with the VIR back in late 70s we paid $444 for brand new.. Great set till the fly shorted. Neighbor had a similar WARD set they tossed with a dead Vertical circuit. Swapped they Flys and it was up and runnin till i sold it years later and the vertical died 2 yrs after and it was tossed..

SR

[NewVista]

Originally Posted by Boobtubeman

Had a Mot WARDS 19" with the VIR back in late 70s .. Great set...

SR

Did it make much difference when you ran it with VIR switched 'on'?

[kf4rca]

As I recall, the vir switch had its own set of controls. So, you could make it look like anything you wanted.
Those vir generators are all over Ebay if you wanted to play with one. Except for the VITS100, they also have a full field test generator with a boatload of test signals. The one I liked was the Tektronix 1910.
I've seen them as low as $30.
But I think the vits deleter and inserter section could be used in eradicating copyguard thats in the vertical interval.

[kf4rca]

Not sure what VIR2 is. Never heard of that.
Even before the HD switchover, stations were going digital in NTSC days.
I remember spots and syndicated programs coming in as a file from a digital satellite.
The files were fed directly to the playout server (a raid 5 computer). And then to air.
Sometimes the programs had low video or high chroma. Since it never went to analog at the station there was no way to adjust it.
This was eventually corrected as stations raised hell with the syndicators. Turns out the spots and programs had been uplinked by a secretary who had no knowledge of video parameters.