[R-390] kilocycle/megacycle movement

[Jim Miller]

Sometimes a coil slug will stick at a band edge causing low sensitivity.
Look at the slug rack as you tune at the high end and see if any slugs stop
moving prematurely.  If you see one, tap on it ot wiggle it by hand to see
if sensitivity returns.  If it is a slug that is sticking, you can usually
free it up by loosening the screws that hold it to the slug rack and allow
it to re-seat itself so it doesn't bind.

Dan Merz wrote:

> Hi,  I haven't used my  390a much over the last 2 or 3 months and I was
> listening on 80 meters tonight and found a problem tuning up near 4
> Mhz.  It seemed dead there and I could tune in stations down near 3.9
> somewhat better (I started listening on another set for comparison to be
> sure the band wasn't dead).  After awhile I noticed that the megacycle
> knob seemed to move off its "lock" position and was moving as I tuned
> the kilocycle knob.  It did this sometimes and would get off the band
> position but not always.  Is this most likely a lubrication problem?  I
> really never was able to pick up a known signal at around 3.99 Mhz and
> I  tried rocking the megacycle knob to improve things,  or to find if
> something else was "hanging up".  I haven't lubed the set since about 2
> years ago when I did a pretty thorough job in this regard and everything
> seemed very free.  I'll pull it open tomorrow and take a look but was
> curious if there was an obvious known component that causes this kind of
> symptom. It seemed ok on other bands but I didn't spend a lot of time
> checking.   thanks,  Dan.
>
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