[Elecraft] Muddy SSB

[Ron D'Eau Claire]

Tim  wrote:
> There are some specific mods, both "Elecraft approved" and others, that
> address some of these issues.  KI6WX has a series of mods he has developed
> that address many of these issues.  ...  In addition, there are some pages
off of the elecraft home
> page that cover some of this.
>
> I have a few questions that will help us to further identify the problems,
> and how to fix them.  What Mic are you using, and how is is wired in the
> radio?  Which mods for ssb have you put in the radio, or is it stock from
> the time you constructed it?
>
> I will look through what I have here that I saved, and if someone doesn't
> have a better answer in the next few hours, I will send some additional
> information to this message.

That's news to me. I thought that I had looked at all of KI6WX's mods and
have chatted with him about some of them. As far as I know ALL of his mods
have to do with receive audio only.

My K2 transmit circuits is "stock" EXCEPT for the 2nd XFIL flattening mod
recommended by Wayne - which affects ONLY receive audio. I made the
variation on that mod that KI6WX suggested that improves the flatness a bit
more.

To answer your other question, I am using a Radio Shack 21-1172D microphone.
Audio recordings using it sound good and, as I mentioned, it sounds fine on
the lower sideband.

I want to make it clear that the audio on USB is quite intelligible, but not
up to the standards of most rigs I hear on the air. The LSB audio is more
like what I'd expect a good SSB rig to sound like.

At first I "assumed" (that word again) that the difference was being caused
by the shape of the ladder filter bandpass that was emphasizing or
de-emphasizing the higher frequencies when the BFO was switched from one end
of the bandpass to the other. But that is NOT apparent looking at the
response with Spectrogram.

Ron AC7AC
K2 # 1289