Quote Originally Posted by sanking
I have seen various activators suggested for PC-Glycol, including sodium carbonate, sodium metaborate, and a combination of the two. Can someone tell me which of the activators gives results closest to those from PC-TEA in terms of developer energy, i.e. speed of development?

I have always used TEA as the activator. From a purely chemical standpoint, sodium metaborate will produce a pH closer to TEA than sodium carbonate. But this pH will still be higher than that produced by the TEA.
For comparison, the pH values for 1% solutions of TEA, metaborate, and carbonate are respectively, 9.8, 11.1, and 11.4.