[Boatanchors] National NC-300 HF oscillator problem

[Mark Foltarz]

 If a previous owner tried a rough handed approach to doing the oscillator
tracking, they might have wiggled the adjusting link in the oscillator to the
point where it has broke. 

  The tracking on this radios must be done with a stable oscillator and a
frequency counter or meter. Otherwise, you can go back and forth, adjusting the
link and  never making any progress on the tracking until the radio magically
quits working - the oscillator link is broken.

 If the oscillator is running you will see a low positive voltage on the grid
with a vtvm or equiv.

de KA4JVY
Mark


--- Glen Zook <gzook at yahoo.com> wrote:
> If all else fails, slightly loosen and then retighten
> all of the hardware (screws, nuts, bolts, etc.) that
> make contact with the chassis (including those that
> hold down the tube sockets, switches, etc.).  Over the
> years these come loose, build up corrosion, etc.  All
> of the grounds in the receiver are made through some
> attachment to the chassis.
> 
> I have "cured" all sorts of problems in "boat anchor"
> equipment by just doing the tighten the hardware bit. 
> This is even more of a cause of problems when they are
> intermittent.
> 
> Glen, K9STH
> 
> 
> =====
> Glen, K9STH
> 
> Web sites
> 
> http://home.comcast.net/~k9sth
> http://home.comcast.net/~zcomco
> 
> 
> 	
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