121

The Tektronix 121 is a wideband preamplifier intended for 511 scopes. The voltage gain is 100, input impedance is 1 MΩ in parallel with 25 pF. The frequency response is 5 Hz to 12 MHz. It has an unbalanced signal path with switchable compensated attenuators before and after the first gain stage, a 6CB6 common-cathode amplifier. The 1121 can be considered the successor to the 121.

Comparison of 121 and 112

The 121 and 112 are both standalone amplifiers produced by Tektronix in the 1950s. A comparison shows their differences.

	121	112
Bandwidth	5 Hz to 12 MHz	DC to 2 MHz
Voltage Gain	100	5000
Year of Introduction	1950	1950
Weight	18 lbs (8 kg)	32 lbs (15 kg)
Price in 1950 catalog	$265	$495
Front View

Manuals

• Tektronix 121 Manual (PDF)
• Tektronix 121 Factory Calibration Procedure (PDF)

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  Block diagram