FG501A

Manuals – Specifications – Links – Pictures

The Tektronix FG501A is a 2 MHz function generator plug-in for the TM500 system.  It replaced the FG501 (1972) in 1981.

Key Specifications

Frequency	0.002 Hz to 2 MHz in eight decade steps
Output	Max. 30 Vp-p (into high impedance)
Attenuator	60 dB in 20 dB steps, 20 dB variable
Rise time	25 ns
Features	symmetry variable from 5 to 95%
Signals	sine, square, triangle, ramp, pulse
Features	voltage controlled frequency input (1000:1 ratio) triggering gated output with variable phase control

The VAR Φ control is effective in triggered and gated modes to control the starting phase of the generated waveform, and therefore also determines the DC output level when the signal is disabled.

Differences to FG501

The FG501 non-A frequency maximum is 1 MHz, while the "A" model is specified at 2 MHz.

The FG501 features seven different functions – sine, triangle, square, positive- and negative-going ramps, pulse ≤50% duty, and pulse ≥50%. The duration of ramp and pulse waveforms is always equal to the half-cycle time of the sine, square, or triangle waveform frequency.

The FG501A model provides only three functions – sine, triangle, and square. However, it has an added variable symmetry control, effectively allowing the same functionality as the non-A model. When variable symmetry is enabled, the output frequency is 1/10^th of the set frequency, as indicated by an orange "FREQ ÷ 10" LED.

The FG501A also adds an output attenuator and increases the maximum open-circuit output voltage to 30 V from the FG501's 10/15 V. The TRIG OUTPUT connector is BNC instead of the FG501's BSM.

Links

• FG507 - same specs as FG501A, added internal sweep generator
• Tektronix FG501A Repair and Calibration/Alignment by Zenwizard Studios @ YouTube

Documents referencing FG501A

Patents that may apply to FG501A

Rear Interface

Connector Pin	Signal
28A	Output from 600 Ω (common on 27A)
27B	Trigger output (common on 28B)
24B	Trigger/gate input (common on 25B)
21B	VCF input (common on 22B)

Family key: Signal source (between pins 23 and 24)

Pictures

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  right interior

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  left interior

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  left interior, sine shaper board unplugged

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  left interior, sine shaper board unplugged

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  right interior

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  left interior

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  front

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  right interior

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  left interior

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  rear connector

Components

Some Parts Used in the FG501A