IHF toneburst generator

For certain audio measurements, the IHF standard discussed elsewhere in this issue specifies a particular toneburst signal: a 1 kHz sinewave, at standard reference level for 480 ms and at +20 dB for 20 ms, then back to stan-dard level for 480 ms, and so on. The level changes must coincide with the zero-crossings of the sinewave.