560

The 560 is a scope introduced in 1961 which uses 50 and 60 series plug-ins for both the vertical and horizontal deflection. The mainframes contain no amplifier stages, requiring the plug-ins to directly drive the CRT deflection plates. While promoted by Tek as having the advantage of “not limited by additional circuitry between the plug-in and the deflection plates”, this configuration has a significant disadvantage. Touching up the gain or sweep cal when swapping plug-ins in scopes with amplifiers in the mainframe can be skipped, as doing so only tunes the accuracy to a small amount of additional precision. But in the 560 series, this step is required to even get crude accuracy, as the raw deflection factor of the CRT has a relatively large range, and the mainframe has no circuitry to normalize it.

Other than the CRT circuits and power supply, the only additional circuits in the 560 are a voltage /timing calibrator. Tektronix referred to the 560 series mainframes as “indicators” rather than oscilloscopes.

The 560 was introduced along with the similar 561 in 1961. A rack model was never offer. Both of the mainframes use conventional 5” round CRTs, with glass envelopes. The maximum system bandwidth of the 560 is 1 MHz. The 561 also supports the 70 series plug-ins, which are not compatible with the 560. Certain members of the 70 series vertical amplifiers give a system bandwidth in the 561 of 4 MHz. The later 2 and 3 series plug-ins can not be used in the 560 or 561, as they consume more power.

The 560 and 561 were short lived, both being replaced in less than a year with the 561A, which offered several performance improvements.

Manual needed.

Photos needed.

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  Description in 1962 Catalog