EERATA SHEET 



for 



DAVID TAYLOR MODEL BASIN REPORT 859 



In Figure h, page 7, the three transformers shown in the carrier ampli- 

 fier portion of the schematic diagram are identical. Cores should be shown 

 in all three. They are manufactured by the Audio Development Company as 

 their type A-5311. 



NOTE: See Figure k, page 7» In later models of the instrument all the 

 calibrating capacitors shown as 17, 3^, 6ij- Il4 uufd, were not in- 

 cluded. Only one, the I06 uufd capacitor was pennanently connected to the 

 calibrating switch, thereby providing an easy means of checking the opera- 

 tion of the instrument. Calibration Is accomplished by actually moving the 

 transducer up and then down in the water. The extra switch section which 

 was required for the calibrating capacitors is not used. 



In Figure 5, page 8, the rectifier tube is erroneously shown as a type 

 6aS7; actually, two type ^k tubes, each with their plates connected in par- 

 allel, are used. 



In Figure 5, both output tubes in the amplifier circuit are type 6y6, 

 although only one is so Indicated. 



