I don't have the board with me -- I'm going out to the shop later today and I can get the number then. The regulator I have is from around 2000, so I don't know what version it would be. There is, however, a fifth power diode (that is not part of the bridge circuit) and a capacitor that are betwen pins 5 an 6. They don't seem to serve any purpose, but the capacitor would absorb spikes, and if the diode reverse voltage exceeded 400 v it would short and stop the generator from generating any AC at all, perhaps preventing a runaway situation on the Q1/2 side...
The second, and perhaps the most important issue in the long run, is the issue of the two MOSFET transistors on the board...
They are obsolete parts, and can no longer legally be manufactured for use in the US or in Europe 'cause they violate some EPA rule -- the MoHS rule. One can still buy them, but the inventories are probably being liquidated with no new ones coming down the line.
Since these generators are still in production, Clearwater must have redesigned (probably tweaked) the regulator to get rid of those MOSFETs. They will likely use a new MOSFET; one that complies with MoHS standards. That is why I am keen to at least look at a brand new one to see what changes were made, if any to get rid of the 450 series MOSFETs and hopefully deal with the bridge rectifier, Q1 Q2 problem.
It is almost ( I said almost) worth the price of a new one just to see the new board, assuming if one purchased a new one that it was indeed, new manufacture and not NOS
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