Philips PM5544 electronic testcard

[ppppenguin]

Putting DC through the terminations won't work because the core is effectively shorting the comparator inputs together. I'll try a resistor in series with each input and then bias at the comparator terminals. The 319 has a low bias current for a comparator, under 1uA, so there shouldn't be any DC problems. The input offset voltage and current are also acceptably low.