AV8073 - Tone Burst generator

Connects to a sine-wave oscillator (like HM8037), delivers a burst of 2, 4, 8, 16, 32 or 64 periods with variable pause.
The circuit diagram is a small modification of a design I made in 1973 which can be found HERE

Top trace: two periods on, four periods off.
Bottom trace: Sync output
Oscilloscope (Hameg HM1508-2)

With variable attenuation set at mid position.

Using external gate signal, TTL-levels from a function generator (like Hameg HM8030-6) enables constant burst and pause length regardless of input frequency. (Which should be at least ten times higher than the gate frequency). Burst start synchronized to input signal.

Top view. Since this is considered a prototype, no special care has been taken for the component placement.

Bottom view.