HI! EVERYONE IN THE MD FIELD. I AM NEW TO METAL DETECTIN BUT YEARS AGO IN THE 60S I BOUGHT A DETECTOR THAT HD TUBES AND A 66 2/3 BATTERYS AND SOME D CELLS TO RUN THE FILAMENT. I DONT REMEMBER THE NAM BUT IT SURE WAS HEAVY AND HAD TWO BOXES SEPERATED ABOT TWO FEET. IT DIDNT WORK VERY WELL BUT I FOUND LOTS OF SQUARE NAILS AND SUCH. THANKS FOR HAVING THISFORUM TUBG