George Massenburg can be contacted at McGill University, Montréal, Québec, Canada. He can tell you. Burgess McNeal would be happy to speak to you and lives in the mountains of Virginia, these days in retirement.

I know your 250's parents.
Mx. Remy Ann David

Thanks a lot
I'm waiting burgess answer...but still no feedback.
So I ask to the forum...here some people talked about sontec 250 diy...so maybe they know something...I hope someone read this...