The module A-142-4 consists of four envelopes with exactly one parameter: decay
Module A-142-4 contains four simple envelope generators. The only time parameter is Decay and can be adjusted manuall by means of the Dec. control in the range 2 ms ... 2 seconds. The attack time can be adjusted internally by means of a separate trimming potentiometer for each sub-unit in the range 1 ms ... 15 ms. The factory setting is about 3 ms. This is the attack time of the TB303.
Each envelope output has a LED control available. The trigger inputs are normalled (1 - 2 - 3 - 4).