Jeff@ubertechnoid wrote Thanks Jeff, it's a while since I read the Wireless World article on the "Chase me Charlie" bomb and I think your're right about the sinking of an Italian battleship. I know it's off topic, but it's quite a feat of engineering stuffing tubes (valves) into shells or bombs. I'm still curious as to how the RF proximity fuses worked. Missile guidance computers are probably a valid topic for discussion on classiccmp. Anybody read Jack Volders paper on the Cordic algorithm ? A true classic. BTW would a "classic algorithm" thread be a valid topic for classiccmp ? It would make a good read and it would be educational too. Chris