Have completed wiring up the four integrator/summer boards. Testing is a bit complicated given the various permutations into which the thing can be configured. My testing scheme is to test in groups of three integrator/summers, with two units being set to INT mode and the other one set to SUM mode. The three units are wired in series. Two of the initial conditions are set to +10 V, the other to 0 V. Correct operation yields voltages which vary as sine or cosine of time.
Have tested two of the four boards. A couple of errors on the second board - namely a missing resistor (tracked down after determining one integrator had a faulty initial condition value), and a misplaced diode. The latter gave rise to the interesting - if impossible - condition of the amplifier being simultaneously over and under loaded.
Picture shows integrator/summers numbers 3 and 4. Wiring needs a little tidying. That's waxed lacing cord (RS 303-1675) by the way...not dental floss(!).
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Have tested two of the four boards. A couple of errors on the second board - namely a missing resistor (tracked down after determining one integrator had a faulty initial condition value), and a misplaced diode. The latter gave rise to the interesting - if impossible - condition of the amplifier being simultaneously over and under loaded.
Picture shows integrator/summers numbers 3 and 4. Wiring needs a little tidying. That's waxed lacing cord (RS 303-1675) by the way...not dental floss(!).
I'll test/correct the remaining two boards. After that, I put these to one side and return to the control unit rack - front panel needs drilling, labeling and populating with its furniture. Then I can finish off the integrator rack electronics (needs dedicated summer circuits - designed, not built, and similarly multiplier circuits).
