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