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I must disagree with some of this.? In fact there was a rush?Because patents were expiring.? The alternate line scanning used for monochrome and color was to reduce bandwidth. A big problem was the

There is also SECAM="System Entirely Contrary to the American Method" and PAL="Picture At Last" ?:) Ozan

The 60 Hertz sync frequency was shifted to 59.94 Hertz. The 15,750 Hertz sync frequency was shifted to 15, 734 Hertz. 8 cycles of studio 3.579540 MHz *(* 315/88) reference frequency was inserted on

and PAL may mean Probably Always Laughing after they saw NTSC. and yeah, I heard that about NTSC.? Who said that variety isn't nice? Harvey

And all these years I thought that NTSC stood for "Never The Same Colour". Jim N6OTQ terrell.michael.a@...> wrote:

NTSC was the "National Television Standards Committee' which originally set the standards for Monochrome Television, then later chose the modifications to allow color without a severe beat in the

59.94 IIRC.? The color subcarrier frequency was chosen to put the energy of the color subcarrier in between the energy created by the monochrome image.? I think they changed the audio subcarrier

As I recall, the "60 Hz" vertical scan rate for NTSC is not supposed to be exactly 60 Hz, but slightly different, to provide color and still maintain integer counting values. Likewise, the horizontal

Hi Michael, What you say about your experience may be be true, on the other hand I have had a 250ft length of CAT5 feeding my Icom R-71a for about 10 years, in Florida, and so far all is good. Plenty

The statement that capacitance decreases as the turns per unit increases is wrong, the capacitance will INCREASE.? Don't believe everything that an AI claims. Leon Robinson ?? K5JLR Political

The impedance can vary with the number of turns per distance. "The characteristic impedance of a transmission line is determined by its physical parameters, such as the diameter of the conductors, the

To add to this… The number of twists per foot determines the differential-mode susceptibility of the cable. More twists per foot, higher rejection of differential energy. It does not improve the

Fifty years ago I fabricated and sold 1-M diameter, single-turn, resonant-loop antennas for the AM broadcast band.? These were designed to recover a virtually noise-free signal for AM broadcasters

I have seen a little discussion of feed line ingress amplitude with coax vs twisted pair. My position was influenced by Dallas Lankford when he was building directional phased MW antenna systems. When

USTP works, but not a good idea in areas with a lot of lightning strikes. Back in the '80s I maintained a 36 channel Cable TV headend. One strike blew out 12 audio inputs on the modulators, and caused

And I should have added that the impedance is measured at a frequency of 100MHz. -- Prof. Thomas H. Lee Allen Ctr., Rm. 205 420 Via Palou Mall Stanford University Stanford, CA 94305-4070

If you take random hookup wire and twist it with some random pitch, you'll often see something closer to 100 than to 150, but 150 is certainly not out of the question. That said, CAT5 is spec'd at 100

I think twisted pairs are closer to 100Ω, I once measured one and got 102Ω. It is dependent in the diameter of the wire and the thickness of the insulation. Using the calculator,

Hi: If the length of coax is less than about 1/10 of a wavelength then you can approximate it with lumped elements, so the Zo is not that important. The impedance of coax is NOT a constant, so when

Interesting topic! Cable impedance vs. loss. I remember reading, many years ago, about power handling vs. vs calculation concerning impedance for coax. The article said 30 ohms was the best power