[hpsdr] Comments on setting up PureSignal

[Bill Diaz]

Brian,
     Based on extensive testing by Mukesh, KE3VG, with a ClearRF 
sampler, good results were achieved on 20 and 40 meters when the 
external sample level was 6db higher than the observed internal 
crosstalk level on that band.  This may not be practical on the higher 
bands due to the higher crosstalk at higher frequencies.

     A table of optimal PureSignal  "ATT on TX" attenuation settings was 
constructed using a barefoot ANAN-100D and various PowerSDR settings.  
Here is the one from my barefoot ANAN-100D:

PowerSDR 3.2.9 Angelia 2.8, ANAN-100D
ATT on TX Attenuation level needed for 1 db above ADC overload at 
various PowerSDR settings:

Band      Alex      Alex Man.    Bypass       Alex Auto and
           Auto      Byp 55mhz    on Tx        Bypass on Tx
                                (EXT1,2)
160       8         0-RED        0-GRN        0-YELLOW
80        12        0            5            5
40        15        2            10           5
20        19        14           15           18
17        21        15           17           18
15        22        20           19           20
12        27        24           18           20
10        22        23           18           21
6         28        26           19           28

Mukesh used a similar table he created with his Barefoot ANAN-100D using 
internal crosstalk.  Then, with his ClearRF sampler attached to the 
output of his Amp Supply amplifier he increased his ATT on TX 
attenuation to 6 db above the level shown in his barefoot table.  He 
then adjusted his ClearRF sampler output to a point 1 db past the point 
where ADC overload was experienced. He acheived ~45dbc using this 
method. YMMV.

Bill KC9XG
On 2/26/2014 9:40 AM, Brian Lloyd wrote:
> ***** High Performance Software Defined Radio Discussion List *****
>
>
>
> Now that people are experimenting with PureSignal with external amps, 
> I think I see a possible trend for an error that can be made that 
> results in less improvement than might otherwise be possible with 
> better configuration.
SNIPPED some great info.

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