[Elecraft] bandwidth question of K2

[Geoffrey Mackenzie-Kennedy]

Chris,

When you say 'without any filter engaged' am I right in assuming that this 
means that you have bypassed the KSB2's crystal filter and the K2's IF 
crystal filter?  If that is the case then the K2's circuits after its TUF 
mixer would behave in the same way as a simple direct conversion receiver, 
whose bandwidth would be determined by the two crystal filter just ahead of 
the product detector and the audio circuits. I don't have my K2 manual here 
to see if there is anything else.

However I suspect that the reason that you heard a station almost 20 kHz 
above where you were tuning is that it was being 'heard' by a spurious 
response of the K2 or your LF converter, or a combination of both. Another 
possibility is that a spurious response of your LF converter was hearing 
some oscillator in the K2, but I am assuming that the station 20 kHz up was 
a real station. If of any help I could run a spurious response check for you 
later this evening (our time) if you would let me know the LO frequency of 
your LF converter, the LF input frequency to which you were tuned, and the 
40m frequency to which your K2 was tuned when you heard the station 20 kHz 
above where you were tuned.

73,
Geoff
GM4ESD




----- Original Message ----- 
From: "Chris Waldrup" <kd4pbj at bellsouth.net>
To: <elecraft at mailman.qth.net>
Sent: Sunday, August 03, 2008 2:24 PM
Subject: [Elecraft] bandwidth question of K2


When I am set to LSB on 40 meters without any filter engaged, what is the 
bandwidth that I can receive?
I am using my K2 as a tunable IF for a LF converter that I experiment with, 
and I heard a station last night that was well above where I was tuning 
(almost 20 kHz) and I am trying to rationalize that to myself.

Chris