[Elecraft] K2 VCO Shield instructions - Freq Counter probe

[Vic K2VCO]

N2TK, Tony wrote:
> Just installed the K2 VCO Shielding Upgrade. The instructions say to
> disconnect he frequency probe and completely remove it from the K2. I used
> to leave it in TP2. Does it really make a difference with anything by
> leaving it in TP2?

Leaving the probe in TP2 increases the amount of BFO 3rd harmonic energy 
  in the output when transmitting on 20 meters.  I verified this by 
listening with a second receiver with the probe in and out.  Not having 
a spectrum analyzer, I can't say if the level of this spur is 
problematic.  If you are driving an amplifier with your K2 you should at 
least check this, since you might radiate a significant out-of-band signal.
-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco