[Elecraft] SSB Filters

Mon Feb 25 22:17:01 2002

Ron:=20

You are absolutely right, it's just build the thing, and remove the 10 =
pf cap, and twist some knobs (one LARGE, several small). I read about =
the "flattening mod", but the Spectrogram came out so nice without it, I =
don't really see the need. The guys on the receiving end don't seem to =
hear the need either<g>.

My rig is stock except for the sidetone cleanups (not very clean, but at =
least better) and C180 being pulled. The "trick" was not to worry that =
my numbers were so very far from the examples (like 400-600 Hz) in the =
book and in diddling L34 by eye, not ear.

Dan / WG4S / K2 #2456

-----Original Message-----
From: Ron D' Eau Claire [mailto:[email protected]]
Sent: Monday, February 25, 2002 8:20 PM
To: Dan Barker
Subject: RE: [Elecraft] SSB Filters

Hi Dan:

By your description of removing C180, I take it you did not put the =
"filter
flattening" mod in that is provided as an Application Note on the =
Elecraft
Reflector.

Just curious, because you managed to get a very nice looking response
without it if that's so.

Wayne/Eric announced almost two years ago that the mod would become part =
of
the r-f board in future releases, but I've not yet seen it hit the =
street.
They may have re-thought the idea.

Ron AC7AC
K2 # 1289

> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of Dan Barker
> Sent: Monday, February 25, 2002 2:40 PM
> To: Elecraft
> Cc: Steve & Anne Ray
> Subject: [Elecraft] SSB Filters
>
>
> Failing miserably to get my K2 sounding right on my own, I
> grabbed the telephone and called Elecraft. I had LSB sounding OK,
> and USB off in left field. None of my numbers were within 400 Hz
> of the "book" values. Gary said that was fine.
>
> Gary talked me through the procedure for a K2 with recent
> firmware and the KSB2 adapter installed.
>
>  a) Bend C180 back and forth until it breaks off, and discard.
>  b) Fire up Spectrogram; and set a marker at 400 and 2200 Hz.
>  c) Move the FL1 BFO freq. until it's balanced between the marks.
>  d) Repeat for the other sideband.
>  e) Diddle L34 to flatten the top of the USB response, but not so
> far as to screw up the LSB response.
>  f) Repeat centering the response curves if necessary.
>
> My results below:
>
>       USB
>
>   Picture suppressed on reflector, see =
http://www.visioncomm.net/ssb.html
>
>       LSB
>
>   Picture suppressed on reflector, see =
http://www.visioncomm.net/ssb.html
>
> I just spend about an hour on SSB with Steve in GA, and he says
> both Sidebands sound FB, and the same. Cool!
>
> So, what's this about a flattening mod? Doesn't really look like
> one is needed.
>
> Dan / WG4S / K2 #2456, KAT2, K160RX, KIO2, KSB2
>
> PS: Now, How do I get on PSK? The MH2 ain't gonna cut it! I'm a
> gonna need some WIRE! (who ever called this hobby wireless? -
> They're nuts!).
>
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