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The Mehikon - broadcast TV color eraser

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Bud:
A curious piece of history of broadcast television in Israel that I never heard of before (source: Wikipedia):
 

--- Quote ---Color eraser (Mehikon)   
In the '70s, the Israeli government considered the import of color televisions as frivolous and a luxury that would increase social gaps. Therefore, the government ordered the Israel Broadcasting Authority to cease broadcasting in color. As it was impractical to strip out the chrominance signal from material recorded in color, this was accomplished by simply omitting the burst phase signal from the broadcast. The "damaged" signal triggered the "color killer" mechanism, installed in color TV sets to prevent the appearance of color. This method was named Mehikon (Hebrew: מחיקון‎ "eraser").

Soon after its introduction of the "Color eraser", special TV sets with an Anti-Mehikon (Hebrew: אנטי-מחיקון‎ "anti-eraser") device were offered. This device re-constructed the burst phase signal according to several known standards. The client had to turn a knob until the pictures on the screen appeared in natural colors. According to a report in Yediot Aharonoth from January 1979,[4] clients had to adjust the knob every 15 minutes on average in normal conditions, or up to 10 times an hour when special problems occurred, in order to restore natural colors or if the picture suddenly turned black and white.

Based on information from owners of electricity appliance stores, the report estimated that 90% of those who bought color TV sets also bought the Anti-Mehikon device, which added about 5–10% to the price of the television.

Eventually, the Mehikon idea was proven to be futile, and the Israeli television stopped using it in 1980, allowing color transmissions to be received freely.
--- End quote ---

tom66:
This reminds me of the reason that SECAM was popular behind the Iron Curtain:  because most of Europe used PAL, it made it difficult to receive (in colour) European signals without illegal imported sets.  Of course, black and white video was still receivable, as SECAM and PAL did not differ there.

It also gives rise to the alternate acronym for SECAM:  System Entirely Contrary to the American Method.

janoc:

--- Quote from: tom66 on August 19, 2020, 09:22:36 pm ---This reminds me of the reason that SECAM was popular behind the Iron Curtain:  because most of Europe used PAL, it made it difficult to receive (in colour) European signals without illegal imported sets.  Of course, black and white video was still receivable, as SECAM and PAL did not differ there.

It also gives rise to the alternate acronym for SECAM:  System Entirely Contrary to the American Method.

--- End quote ---

That is nice story but very unlikely to be true.

The originally French (and European standard) SECAM was used in the Eastern bloc because it was used in Soviet Union since 1967. For example, Czechoslovakia didn't start with regular color broadcasts until 1973-75. So it was logical that they picked the same technical standard as what was used by the Soviets already (all the labor division within COMECOM).

Why Soviets picked SECAM is likely due to the fact that it was an European standard, it wasn't German (all the WWII stuff) and, crucially, PAL didn't even exist when the decisions were made yet.

And given the geography, people in Moscow (and most of the Soviet Union, really) really didn't need to worry about receiving any illegal foreign signals in offensive color.

FYI, both SECAM & PAL were designed explicitly to fix the problems of the "American method" (aka NTSC).

Benta:

--- Quote from: tom66 on August 19, 2020, 09:22:36 pm ---This reminds me of the reason that SECAM was popular behind the Iron Curtain:  because most of Europe used PAL, it made it difficult to receive (in colour) European signals without illegal imported sets.  Of course, black and white video was still receivable, as SECAM and PAL did not differ there.

It also gives rise to the alternate acronym for SECAM:  System Entirely Contrary to the American Method.

--- End quote ---

Like janoc says, nice story for the pub, but that's about it.

All the systems have B/W compatibility, only colour coding is the issue. SECAM was probably chosen by the USSR as it seemed the most mature system (development started in the 1950s).

More efficient in the East Block when warding off "imperialist television" was the audio carrier frequency offset, which gave the option of either seeing a western broadcast without sound, or just hearing the audio.

Halcyon:

--- Quote from: janoc on August 19, 2020, 10:20:54 pm ---FYI, both SECAM & PAL were designed explicitly to fix the problems of the "American method" (aka NTSC).

--- End quote ---

There is a reason why NTSC was commonly referred to as "Never Twice the Same Colour". I always did appreciate the extra resolution of PAL.

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