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N1MM Spectrum display with Hackrf1

N1MM does offer a Spectrum Display  that can display a panoramic view some  newer radio's support band data from the first broad m.f.  like the IC7300
Radios that connect to the PC using USB or WAN can offer a data stream to N1MM Spectrum Display so older types need an other solution.

My K3 is connected with rs232 for CAT for low speed serial data  like frequency mode
T/R CW keying 
The Hackrf1 i recently got can be used  if your K3  has the Xverter I/O option.
Hrf1 should already be working okay with SDR-console or SDR# before trying to connect with N1MM Spectrum Display
Download ExtIO_HackRF.DLL
This ExtIO_HackRF.dll   must be copied to the N1MM  program directory.
   C:\Program Files (x86)\N1MM Logger+
Connect the  Hackrf1 with the IF out.
Hrf1 USB should be pluged in , no other  SDR program must be running with it.

Start N1MM like used to  then open window Spectrum Display
In my case the N1MM Spectrum display automatically found the ExtIO driver.

the left configuration window  tab 3   the button in tab 3 opens a smal window where bandwidth and gain settings of the Hrf1 can be set

The Hackrf1 is receiving at the i.f port 8.215MHz
I reduced the Vga gain to 10dB and maximized the Lna  to see more details in he spectrum
I found it not easy to see in  the spectrum CW or  LSB signals in this case on 40m since the default noise line is a bit high and hiding the wanted signals.
I have done the Elecaft K3 IF buffer mod for low serial K3 mine is serial 1404
replacing main PCB back R8 1k by 13k
Possible an other amplifying filter adaption is needed to gain a better dynamic range
The strongest  signal 9+30 40  show no more then +20 dBm over the noise in the spectrum now.
Before i have used Hackrf1 with SDR# tuned at 8.214MHz  then during the CQWPX phone i could see phone  signals very good but then the frequency in the spectrum display does not correspond with the K3 tuning
The Hrf1 did receive well and also the audio was fine at  the K3 i.f. out.
 I was expecting similar result using N1MM Spectrum  but it is not so good  possible some setting is wrong? But have not found any setting to improve the spectrum view
anyway this is an easy way to have a band scope.
 - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

WSPR 80m

Still  the distance calculation of WSPR spots in the morning grey line is wrong.
the km DX  should be just the other way calculated over the south-west not over North East
Morning path to ZL is over G CT to S-W so we have 19651+ km to ZL  CT is closer..

 2020-04-06 06:22  CT1EYQ  3.570173  -23  0  IM58ob  5  ZL2005SWL  RE68mx  19651  205 
 2020-04-06 05:08  DK2DB  3.570041  -25  0  JN48fw  5  ZL2BCI  RE79nd  18636  54 
 2020-04-06 05:16  PA0O  3.570028  -24  0  JO33hg  5  ZL2BCI  RE79nd  18387  37


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