[Elecraft] [K1] Spectrogram Question

[Don Wilhelm]

Clark,

What were you using as input to the K1 antenna?  You must have a source 
of wideband noise that is well above the noise floor of the receiver to 
see a well defined passband shape in the Spectrogram display.

If you did have a good display of the passband shape, and you see little 
reduction in the width of the filter, then yes, you may have a problem 
and need to 'take out the screws'.  If you do have such a problem, it 
can probably be traced to the varactors used to vary the capacitance in 
the crystal filter or the control of the voltage applied to those varactors.

73,
Don W3FPR

Clark Macaulay wrote:
> I finally decided to test my older K1 with Spectrogram and found the BFO frequency so close to the center of the filter it wasn't worth the trouble to pull the screws from the cabinet and try to get the BFO moved closer.
>    
>   BUT I did notice something: when changing between the three filters the width of the plot varied very little.  I would have expected to see a vastly different shape between the 800 Hz filter and the 250 Hz filter.  
>    
>   So, do I need to take the "screws" out anyway? 
>
>