[hpsdr] Proposal for a 'low-end' RX/TX board for HPSDR

[Robert McGwier]

Robert McGwier wrote:
> ***** High Performance Software Defined Radio Discussion List *****
>
> The six meter band is so quiet that the optimal QSD will not be quiet 
> enough in all cases and a preamp will be required.  It is good we know 
> we are starting with circuits that have the noisier as we go higher 
>   
noisier as we go higher problem FIXED

> problem.  This minimizes the amount of gain and the attendant decrease 
> in OIP3 that results.
>
> Bob
> N4HY
>
>
> KD5NWA wrote:
>   
>> ***** High Performance Software Defined Radio Discussion List *****
>>
>> Lower QSD noise is a good thing, and a worthy goal, but is not the 6M band so 
>> quiet that it would benefit from a pre-amp anyway in order to receive very 
>> weak signals?
>>
>> Signals so weak that in the lower bands they are masked out by atmospheric 
>> noise but not so in the 6M band.
>>
>> Even with lower QSD noise the noise of the sound card has to be overcomed 
>> also, although the figures comming out of the Janus are simply wonderful.
>>
>> Fix the QSD problem if it's fixable but I would not count out a low noise 
>> pre-amp. With a lower noise QSD you might not need very much gain but it 
>> might be nice to be able to kick it in if needed.
>>
>>
>>   
>>     
>
>   


-- 
AMSAT VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats,
NJQRP/AMQRP, QRP ARCI, QCWA, FRC. ARRL SDR Wrk Grp Chairman
"An expert is a man who has made all the mistakes which can be
made in a very narrow field."  Niels Bohr


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