开云体育

Applicability: Any Johnson Transmitter using the Johnson Ball Drive Assembly

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1) Johnson Ball Drive assembly uses 3/16" ball bearings (3)

2) We have found cases of the balls showing a "flat spot"/galling resulting in a "glitch or hesitation" in the ball drive input shaft rotation

3) This "flat spot"/galling results from over-tightning of the outer tensioning nut which crushes the wavy-washer, resulting in the balls in the assembly being "dragged rather than rotating" in the input shaft concave drive recess.

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1) Disassemble ball drive mechanism

2) Clean thoroughly

3) Replace the three balls ( McMaster Carr has these: 3/16" stainless balls)

4) Polish the input shaft concave ball drive recess ( We chuck the ball carrier assembly in a drill motor, polish the concave drive recess with 1000 grit wet or dry) rinse and dry.

5) Carefully re-tension ( bend) wavy washer. If wavy washer is missing, McMaster Carr has a suitable replacement.

6) Re-assembly ball drive assembly, don't be stingy with lubricant ( we use lubriplate)

7) If your Ranger does not use a "floating snubber", and the ball drive uses the front panel as a support structure, tighten the "tensioning nut" only enough so the dial pointer rotation is smooth and does not "skip" .

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Hi Ashley.? I'm currently restoring a Navigator and the ball drive is rather rough.? Maybe you can explain what needs to be done to get the ball drive mechanism out of the VFO.? I know there is in insulated shaft coupler on the VFO tuning shaft, but there seems to be no way to get to that without removing the VFO assembly from the chassis.? I've never had one of these VFOs (Ranger or Navigator) off of the chassis, so any tips you may have on that would be appreciated.? I'm going to order the new ball bearings from McMaster Carr.? Thanks much for identifying the size and source.? When I lived in Raleigh, we had a bearing distributor who sold nothing but bearings and I used to just take a worn bearing in and they'd identify the exact material and size for me.? No such luck here in the mountains of northwestern NC.??

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