Module A-110-2 is a low-cost voltage-controlled oscillator.
It's a slightly reduced version of the standard VCO A-110-1. Compared to the A-110-1 the A-110-2 has no sine output and the (expensive) octave rotary switch is replaced by a 3-position toggle switch. In return the A-110-2 is equipped with an additional linear FM input and a soft sync input.
A jumper is used to select the range of the tune control between about 1/2 octave and about 4 octaves. The width of the module is only 8 HP compared to the 10 HP of the A-110-1.HP : 8