Hi Mooneer,

Looking at the image - yes that's being overdriven on tx somewhere.  In 
particular the "grass" at either side of the signal is only 20dB down.

Try backing off the radio mic gain and/or output level from the SM1000 
until you get a nice clean spectrum.  Then you might be able to bring 
the power back up again.  This blog post:

   http://www.rowetel.com/blog/?p=3109

has a video demonstrating exactly this issue (6 minute mark in video).

Cheers,

David

On 19/05/15 17:00, Mooneer Salem wrote:
> Hi David,
>
> Lowering to 1 bar of ALC on the KX3 appears to have lowered effective
> output power to 2W. I also moved the dummy load so that it's about 3-4
> feet away from the IC-7200 and lowered RF gain on said rig (was S9 or so
> at max gain). I posted a couple of screenshots at
> http://imgur.com/a/YSAF7 that seem to indicate little change in results.
> I'm going to let the KX3's batteries recharge overnight and try a couple
> of other things tomorrow.
>
> Thanks,
>
> -Mooneer K6AQ
>
> On Sat, May 16, 2015 at 11:45 PM, David Rowe <[email protected]
> <mailto:[email protected]>> wrote:
>
>     Hello Mooneer,
>
>     Try backing off the tx drive so that your average power output when
>     using FreeDV is 2W and see if the SNR improves.  On a 100W PEP SSB radio
>     20W is a typical average power
>
>     Unlike other digital modes FreeDV has a fairly high peak/average power
>     ration (similar to analog SSB).  Hence we recommend just 1 bar of ALC.
>
>     Also try reducing RF gain on yr test Rx, possible there is some clipping
>     there.  Overdriving at either the tx or rx side will be evident by a low
>     SNR, poor scatter diagram, or "grass" either side of the spectrum.
>
>     Some more notes in the SM1000 User Guide, you may have seen these
>     already.
>
>     Thanks for your kind comments on the SM1000 :-)
>
>     Lets us know how you go!
>
>     Cheers,
>
>     David
>
>     On 17/05/15 15:19, Mooneer Salem wrote:
>      > Hi all,
>      >
>      > I received my SM1000 the other day and have been working on setting
>      > proper levels with my KX3. Since I don't have any attenuators,
>     I'm using
>      > a dummy load placed close to an IC-7200 connected to a PC running the
>      > FreeDV application to check spectrum and plots. KX3 is set to 5 watts
>      > output.
>      >
>      > However, it appears that I have to set the Rig Mic pot on the SM1000
>      > cranked all the way to the right and to set the KX3's mic volume to
>      > somewhere in the mid 40s to get a full 5 watts out. Is this expected?
>      > Also, the ALC doesn't appear overdriven (in fact, it might still be
>      > under-driven since Elecraft recommends 3-4 bars for other digital
>     modes)
>      > yet I can only get a maximum SNR of ~10dB according to the FreeDV
>     app.
>      > BER also appears to be higher than expected for a signal source
>      > extremely close to the receiver at around 0.015 or so and the scatter
>      > plot doesn't seem to be that tightly grouped either.
>      >
>      > Any idea what the problem could be? Hopefully I just forgot something
>      > somewhere and/or this is simply a result of my non-optimal test
>     setup.
>      >
>      > (BTW, I love how this thing is pretty much plug and play if you
>     have the
>      > cable kit from Elecraft--one cable each for the KX3's mic and speaker
>      > and one to ACC2 for PTT; ACC2 IO = PTT LO in the settings menu
>     completes
>      > the configuration.)
>      >
>      > Thanks,
>      >
>      > -Mooneer K6AQ
>      >
>      >
>      >
>     
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