[Central-Electronics] RE: Sideband supression

[K6JEK]

Thanks for the tip.

At one point I had my 100V down to 50 dB below at 1 kHz but it was  
only 30 dB down at 2 kHz and 25 dB down at 400.     I was optimizing  
for LSB.  I imagine the USB situation was worse.  It makes sense to  
have the best opposite side band suppression where most of the audio  
power from your voice resides.   Is that 1 kHz?

I talked with my phasing rig expert friend, Rod, KQ6F.   You can read  
about his homebrew phasing  rigs in QEX.   He says the big challenge  
with phasing rigs is even phase shift across the audio spectrum.   In  
his homebrew he divides the audio spectrum into five bands with  
separate phase shift circuits and separate adjustments for each  
band.   However, he has the luxury of using op amps.   That's  
cheating, don't you think?

BTW.   His homebrew sideband transmitters sound superb -- the best  
I've ever heard from anything including Flex Radios and CE rigs,  
although the CE rigs might be in second place.   I'm biased, of course.

Jon

On Mar 14, 2008, at 5:37 AM, Steve Hobensack wrote
On Mar 14, 2008, at 5:37 AM, Steve Hobensack wrote:

>
>
>
> I use Rycom selective level meter to finish off the adjustments.  
> There are many brands of selective level meters sometimes called  
> selective volt meters at reasonable prices on the bay. I have a  
> CE-10B, I get it the best possible with a cheap scope to about 38  
> db down, then the Rycom will get it to 42 db down. Never thought to  
> to check at other audio frequencies from 1.2 khz.
>
>
> ..Steve...N8YE
>
>
> _________________________________________________________________
> Connect and share in new ways with Windows Live.
> http://www.windowslive.com/share.html? 
> ocid=TXT_TAGHM_Wave2_sharelife_012008_________________________________ 
> ______________
> Central-Electronics mailing list
> Central-Electronics at mailman.qth.net
> http://mailman.qth.net/mailman/listinfo/central-electronics