[Hammarlund] HQ170A main tuning slop

[GRANT YOUNGMAN]

No, there’s no real adjustment in the flywheel per se, except to make sure everything is snug to minimize “in and out” slop on the tuning knob shaft.  Some random thoughts … 

Is it possible that the pinch wheel that drives the left hand dial is loose, or that some grease has found it’s way onto the edge of the left plastic dial?  (The dial rim and the pinch wheel need to be squeaky clean, and the pinch wheel needs to grip the tuning dial solidly throughout the wheel’s 360 deg rotation).  If the drive string that moves the right dial is loose it might make the motion of that dial sloppy, but the left dial drives the tuning capacitor directly.  Could be a slightly loose coupling between the left dial and the tuning cap(?).

In any case, I’d focus on the pinch wheel mechanism and the attachment of the left dial and the tuning cap shaft for starters.

Grant NQ5T




> On May 16, 2015, at 10:42 AM, Robert Sauvan <rsauvan at beyondbb.com> wrote:
> 
> Hi all,
> Was wondering if anyone is familiar with how I might go about adjusting the main tuning knob in my HQ 170A if it is even possible. I have a fair amount of "slop" in the knob making it very difficult to tune precisely. Its been a while since I have had the unit out of the case but I dont recall seeing any screw or adjustment for that "flywheel" on the backside of the tuning knob. I dont believe it is slippage in the string since it doesnt really slip. I am hoping it is just a screw that I can tighten to adjust the slop out of the mechanism. Anybody ever had to deal with a similar issue and how did it get resolved if you did?
> 
> Thanks-Bob-W0YBS
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