Ameritron TR-30 Antenna Tuner Problems

 

Defective Roller Inductor: The roller is pushed away from the coil by the coil supports.




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The problem with this unit is that the holes for the shaft that hold the roller are drilled out approximately 0.05" too far away from the center control shaft.  Instead of rejecting this batch, MFJ attempted to skew the roller shaft.  

Ameritron knew these inductors were defective, but tried to compensate for the defect.  This was apparent when I SAW THAT THE ROLLER SHAFT WAS AT THE 12 O'CLOCK POSITION AT ONE END, AND AT 2 O'CLOCK AT THE OTHER END.  This was a blatant attempt to increases clearance that failed miserably.

Skewing the roller shaft created another serious problem:  The roller binds to the shaft instead of turning.  This results in the eventual wearing away of the silver plating on the inductor!



Ameritron ATR-30 Edge Wound Inductor


Roller is pushed away from inductor by excessively deep notches in guide #3


Dark marks on G-10 inductor support indicate roller rubbing, resulting in
 reduced and sometimes no pressure on the inductor.  This results in
 intermittent performance, heating, and sometimes arcing. 

 


click here for MPEG video