Lords of the Ring

[kames]

@Turbo,

I can add some stuff to your compilation file but it has to be in the MS Word format. I cannot use any program that modifies any pdf file on my machine. That is the policy on my computer for other reasons.

The reason why this delay line is so important is because if you want to put a device into a self-oscillating mode and generate short pulses, the delay line is the way to go. This is not applicable for a sine like signal but might be okay for a signal with the wide range of spectrum.
My strong opinion is that the delay required for the tpu has to be VERY consistent if not to say the same all the time and not affected by anything. It also has to have a specific value related to the required frequency, a kind of resonance.

If you are okay to add some info to you file about a delay line, below is an extract from a couple web sites. I can put it in a word file if needed.


A basic television picture has two layers:
A high-definition, monochrome brightness layer that we call luminance.
A low-definition, colored layer that we call chrominance.

Why a delay line? A delay line keeps the faster, luminance image in step with the slower, chrominance image. The narrowband chrominance signal requires more processing than the wideband luminance signal. This processing takes a brief, but significant time. The delay line assures that the two images start scanning across your screen at the same time. Without the delay line, you might notice that the monochrome picture starts before the color overlay does.




Following the NTSC, SECAM was patented in 1957 and PAL in 1961. The most important goal of both the SECAM and the PAL was to eliminate the major drawback of the NTSC system: its sensitivity to phase errors. Although choosing different ways, both were successful and what is interesting: both rely on a very particular electronic component the mass-production of which became possible just by the end of the '60-s: the electromechanical delay-line having the delay of one TV line (64 ms).

[gn0stik]

This is interesting information, for sure, however The example exploding TV we have takes place in america, which is all NTSC. This says that pal and secam rely on delay lines. Does NTSC too? Perhaps it's the very absense of this delay feature that allows it to achieve critical resonance, and implode?

Now, I tried to find examples in the media of stories about old tv's imploding and killing people but I could not. If this phenomena took place in europe as well as N america, then I would agree that the imploding is independent of the inclusion of this feature of PAL and SECAM.

However, either way, it wouldn't seem to a factor in causing it. Or did I misread something?

Rich

[kames]

@gn0stik
The delay line is applicable to any color system except for digital. The main reason is an analog modulation for tv signal with a very wide spectrum (not sound part of the signal). The newest tv don?t use a half-mechanical delay line. That was very old. All new systems use on-chip electronic delay lines, such as a temp memory. It provides the way of putting all the layers (colors and brightness) in sync. Depending on the country and a color encoding type, one or another channel has to be delayed. One or another way has advantages only in a way what is less sensitive to a human eye. The phase distortion in color tv is terrible in the same way as very high harmonics in sound technology. For example, a 20MHz harmonic can make the sound very bad despite that a human being can normally hear only up to 20K.
What I wanted to say, is that when all the signals/channels come to specific sync mode, the explosion might occur. That specific sync mode has to stay at least for a very short moment in phase sync for a catalyst to start. And that specific mode depends on the quality of the delay line and may be some broken (not exact delay that was needed) circuits.

I also tried to find some stories in the media about exploding tvs and killing people. The result was zero.

Kames.

[turbo]

@ Kames

Thank you 4 the explenation i will add it to the document along with other things. 

I was just reading about the exploding tv's in 1965/66

1965/66 was the exact year the first televisions came to market which had so called "solid copper circuits" which replaced the old fashioned "hand wiring"

So, that would mean the first television set's with what we call the PCB or "printed circuit board"

Turbo.

[Dyamios]

TV implosions would more or less be a result of manufacturing defects. An implosion of the smaller cathode-ray tubes used in older television sets would not be likely to kill someone either. If a person was standing near enough to a large enough CRT, the implosion may cause damage to the timpanic membrane of the ear (ear drum), and possibly lesions to the skin from glass shards (granted, if a piece of glass hits a major artery, it may be fatal), but other than that no serious injury may result.

I also doubt that any mechanical resonance of the CRT would have enough energy to fracture the glass, and even if it did, it would be more likely that a hair-line fracture of the glass (which would most likely be the result of resonance) would merely result in a sharp hiss of air entering the CRT rather than a full-fledged implosion.

My two cents.