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SCHEMATIC CHANGES AND EQUIPMENT DIFFERENCES



SCHEMATIC CHANGES AND EQUIPENT DIFFERENCES REFER TO SCHEMATIC SHEET
=1=> through =11A=>
=12=> through =20A=>
=21=> through =27C=>
=28=> through =36B=>
=36=> through =39=>
1
2
3
4
5
IDENTIFIER DESCRIPTION

<=1=
 
 
 
 
 

<=2=
 
 

<=3=
 
 
 

<=4=

R51 and R52 330 kW and R53, 27 kW was 18 kW. R51 and R52 can be either 310 kW or 390 kW but must be the same, If R51 and R52 are 330 kW. R53 should be 27 kW; if R51 and R52 are 330 kW If R51 and R52 are 390 KW, R53 should be 18 kW This change provides a 1750-Hz tone oscillator frequency If replacing onc or more of these resistors recommend replacing with values shown on schematic and also replace R50 as noted In

R50, 47 kW I watt was 47 kW 1/2 watt This change gives longer resistor life at existing power dissipation level. Recomend that R50 be lnspected when the Unit is being repaired for any reason, and lf R50 is 1/2 watt replace it with l-watt resistor

L38 and L41, 1 mH, were added C6; 1 µF was 0.47 µF; C264, 20 µF was 4µF: CR10 1N1490 was added; and R208 470 ohms was added as 100 ohms then changed to 470 ohms These changes block rf feedback that nmay cause audio distortion If these components are not in the unit they do not have to be added lf replacing any of these components, recommend replacing with values shown on schematic

Some early units have a balanced modulator circuit as shown below. Recommend that modification to the circuit shown on the schematic not be attempted If repairing balanced modulator circuit as shown below, replace components with values shown here and In the parts list

KWM-2 and KWM-2,A Transceivers. Schematic Diagram
figure 7-l (Sheet A)

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