Assistance needed on a schematic

[mitrynicolae]

Hello everyone,

Could someone please describe to me as detailed as possible on how the attached schematic work?

The schematic is from a comparator and I have identified the following subcomponents:
-q7, q8 are forming a current mirror
-q1-q2 and q3 q4 are darlington pairs
-q5 is the open collector output.

What it is not clear is
-how exactly the inputs are compared (a detailed explanation will be very appreciated) (from my understanding if positive voltage is applied for example to q1 then the transistor is off. If this is true then how is the comparison performed?)
-if in+ is greater than in- what is the value of the output (floating or connected to ground)?

[soldar]

You can see two similar halves. As long as both inputs are the same the collectors of Q2 and Q3 have the same current. Now vary -input and it will cause the collector current of Q3 to vary and this difference will go to the base of Q6.