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146: Difference between revisions
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See also [[140]] and [[144]]. | See also [[140]] and [[144]]. | ||
Regarding the 146, [[Phil Crosby]] recalls: | |||
<blockquote> | |||
It was probably a [[Steve Roth]] design, although he may have gotten help from [[Dave Jurgenson]]. | |||
Steve was a wizard. | |||
He designed the goniometer for doing seamless phase adjustment and all of the early video test signal generators. | |||
The first test signal generator was the [[141]] PAL generator. | |||
We had wanted to do test signal generators for a long time, having spent a lot of money for a Riker generator, | |||
which we were told was the top of the line. It was terrible! | |||
The color bars were just hard-switched between the various phase and amplitude sources. | |||
Generating horrible transitions. Other than that, it was a drifty, mechanically horrible piece of crap. | |||
The PAL version of the vectorscope, the [[521]] obviously needed PAL test signals, | |||
particularly linearity staircase and color bars to be calibrated and evaluated. | |||
There was a source. Some Swiss division of RCA said that they could supply us with such a generator in 18 months for about $18,500. | |||
Steve was coming free from the work I'd given him on the [[520]] NTSC vectorscope, | |||
so I asked him if he would be interested in doing a generator for PAL. | |||
I knew it would be tricky because of the subcarrier frequency offset. | |||
Steve also decided to use these newfangled integrated circuits | |||
(RTL, unfortunately, since I had used them in the 520 cuz they were cheaper than TTL Ouch!). | |||
In six months we had working prototypes and I took one to the 1968 NAB show in Chicago. | |||
It made a big hit with the FEs because they had something to demo PAL vectorscopes to systems sellers. | |||
With the groundswell response from the field, in about six months we had product approval. | |||
The 148 followed with Steve's sync separator circuit employing a transistor that is reflexed into common emitter, | |||
common base, and common collector operation at the same time. | |||
As I recall the 146 had the sync separator for its genlock and maybe it went to TTL as well. | |||
Brilliant! | |||
</blockquote> | |||
{{MissingSpecs}} | {{MissingSpecs}} | ||