[Elecraft] Bass in audio is good

[Brian Lloyd]

On May 5, 2008, at 1:35 AM, G4ILO wrote:

> Mike Scott-7 wrote:
>>
>> I am surprised to hear that people don't like the extra bandwidth  
>> in the
>> audio response in the K3.
>>
> Because people use their radios in different ways. Some of us don't  
> want to
> waste energy generating frequencies that add nothing to the ability  
> to be
> heard when signals are weak. We don't use SSB to have "armchair  
> copy" chats
> using hi-fi speakers.
>
> Nobody is asking that improved low frequency response should be  
> taken away,
> just that it should be made an option. I'm not sure that the range of
> adjustment provided by TX EQ is great enough to restore the audio to  
> the way
> it was before.

I feel lots of heat but very little light on this subject here. There  
really is no problem. A SSB transmitter is just a linear translator  
that moves your baseband signal (audio in this case) up into the RF  
spectrum where you want it. When you mix to translate the signal  
somehow you need to get rid of the image. That means either filtering  
it out (filter-type SSB generator) or cancel it out (I/Q type SSB  
generator). Regardless, it doesn't matter whether you provide the  
bandwidth shaping at baseband or after your first mixer. DSP at  
baseband, DSP at the first IF, or a crystal filter at first IF or  
second IF doesn't matter. Any will solve the problem for you.

I think Elecraft has already thought this out.

Next we will talk about how it is ALL digital, that there is no such  
thing as analog. ;-)

Claude Shannon for President.

Brian Lloyd
Granite Bay Montessori School          9330 Sierra College Bl
brian AT gbmontessori DOT com          Roseville, CA 95661
+1.916.367.2131 (voice)                +1.791.912.8170 (fax)

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