The TG300 series are precision 3MHz function generators with waveforms of sine, triangle, ramp. pulse and DC from a variable amplitude 50Ω or 600Ω output. A TTL/CMOS auxiliary output is also provided. The frequency range is 0·03Hz to 3MHz selected by a seven decade range multiplier and calibrated vernier. Both the frequency vernier and the sweep input can give 1000:1 frequency change within a selected range. A 10:1 symmetry range permits ramp and pulse waveforms to be produced. The generator output level is 20Vpk-pk maximum from a 50/600Ω source. The level is set via a switched attenuator plus vernier with a total range of >80dB. DC offset is vernier adjustable over a ±10V range with centre detent for 0V. Waveform quality is good at all frequencies and signal levels. All models feature a large liquid crystal display shows frequency and amplitude simultaneously. Good resolution and a fast display update rate are maintained at all frequencies. The TG330 also has internal LIN/LOG sweep with sweep output and AM. Amplitude modulation of up to 100% is possible using the internal 400Hz oscillator or an external source. On the TG320 and TG330 the display can also be used as an external 120MHz frequency meter with up to 7-digit resolution. Additional display annunciators indicate generator status when sweep, AM, etc. are in use. 2