3A5

The Tektronix 3A5 is a 15 MHz "Automatic/Programmable Amplifier" plug-in for 560-series scopes. It can automatically seek and select a suitable deflection factor to display an unknown signal.

Range seeking is initiated through a switch on the unit, a button on the P6030 probe, or a signal through the PROGRAM connector (using a 263 programmer).

The 3B5 is a time base with similar features.

Key Specifications

Deflection	1 mV/Div to 50 V/Div , 1−2−5
Bandwidth	15 MHz (50 V/Div to 10 mV/Div), 5 MHz (5 mV/Div to 1 mV/Div)
Seeking circuit frequency range	30 Hz to 20 MHz
Input impedance	1 MΩ // 24 pF

Links

• Tektronix 3A5 and 3B5 Automatic Seeking Mode @ YouTube
• Automatic / Programmable Plug-ins @ vintagetek.org
• Tek 3A5 @ barrytech.com

Pictures

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  Manual mode block diagram