[Drake] Drake Xtal Eliminator - Spurs anyone?

[Tom Hammond]

Hi Folks:

Has anyone else managed to get their (Hageman) Drake Xtal Eliminator build 
and installed?

If so, how bad are the spurs you're hearing?

I'm hearing a number of relatively low-level spurs, almost ALL within the 
bottom 50 kHz of each ham band (right in the middle of the CW section).

For the most part, the spurs are low enough in level that they don't 
significantly effect received signals which are S-1 or stronger, but 
they're still there, and do make copy a bit more difficult... and less 
enjoyable.

I have noted that, on 20M at least, when I'm copying a strong signal, I 
hear additional beat notes on either side of the main signal. I'm wondering 
if this might indicate excessive injection... anyone care to comment upon 
this? I've not yet tried reducing the coupling cap, but that will be 
something I'll try.

I also noted that the 10MHz oscillator has some pretty strong harmonics, 
even though the oscillator's enclosed. I guess the signals are sneaking out 
via some of the other signal paths.

It's a good thing that I changed R100 (originally 47 Ohms 3W) to a 5W 
resistor... even at 5W dissipation, that resistor gets plenty 'warm', as 
does the aluminum box to which all three Vregs are physically attached for 
heatsinking. They'd BURN UP if they weren't screwed to the box.

If you HAVE gotten your project built and installed and found that the 
frequency was off by about 5-8kHz, try replacing the 10MHz master 
oscillator xtal (Y1) with a 10MHz SERIES-resonant (18pF load) xtal. I think 
the xtal I received from FAR circuits may have either been mis-cut or was a 
parallel-resonant xtal instead of series-resonant. Replacing it with a 
series-resonant xtal eliminated my off-freq readings.

I'd really like to hear from anyone else who might have completed their 
Xtal Eliminator and have it installed... at least HOOKED UP, if not 
completely 'installed'.

73,

Tom Hammond    N0SS