[Elecraft] Sound Generator / Audio Generator ??

[Ron D'Eau Claire]

What you describe is what is often called an "audio generator". It is
NOT needed to build and align your K2!

Such equipment might be handy for troubleshooting, but only in very rare
situations where you want to text the bandwidth of the audio system
using square waves, etc. 

Are you perhaps thinking of an "RF Noise Generator". It is a device that
produces a low-level "white" noise across the HF spectrum. They are
discussed here from time to time. Having one makes it SLIGHTLY easier to
set up the BFO frequencies in your K2 so the IF filter bandpass is where
you want it in each bandwidth setting using Spectrogram. You want a
source of noise that covers enough spectrum to produce an output across
the bandpass of your filter at its widest setting.  Normal "band" noise
that you will find on, say 80 or 40 meters (especially with the
preselector On), will do this just fine. Having a separate noise
generator ensures LOTS of noise and you don't have to worry about a
signal or spur from something drifting across the bandpass that might
confuse you for a second. Again, an RF Noise generator is definitely NOT
REQUIRED to align the filters. It just makes it a little easier on some
cases. 

Look on the Elecraft web site at www.elecraft.com under "Builder's
Resources", "Elecraft Application Notes" for the link to "K2 Filter
Adjustment and Mod Articles (Includes using Spectrogram)" for more
information about filter alignment. 

Again, all you NEED to build your K2 is a decent ohmmeter to do the
voltage and resistance checks. Having a separate DVM makes voltage
checks a little easier. You don't need to use the built-in voltmeter
function in the K2 if you have a DVM. The ohmmeter is needed to do the
resistance checks called for to check your work at points along the
assembly process. The ohmmeter must be a "modern" one that does not use
a big battery for the ohms function. The antique "Simpsons" and the like
that were popular into the 50's and 60's use fairly large batteries that
would "fry" half of the solid state in your rig if you tried to use one
of those for resistance checks. Any newer ohmmeter designed for use with
solid state gear is fine. 

Using Spectrogram makes aligning the filters a LOT easier than "doing it
by ear". 

Using an RF Noise generator makes aligning the filters using Spectrogram
slightly easier, especially if you live in a VERY RF-quiet location. 

Have fun, David!

Ron AC7AC
K2 # 1289. 


I am just getting started on my K2 Kit.  I have seen 
many postings about a "sound generator" for testing.  I 
have a "BK 3001 Sine / Square Wave Audio Generator" 
laying around with my tools.  I picked it up a while ago 
but don't use it.  Is this the same thing as a "sound 
generator" and could I use it for testing my K2 kit.

Thanks
David Davis, KG6MTI