[amsat-bb] Doppler PSK

aflowers at frontiernet.net aflowers at frontiernet.net
Mon Jan 23 14:51:14 UTC 2017

I sent Joe the documentation directly.  If the site isn't fixed in a little while I'll find somewhere else to put them.  In the meantime, if anyone else needs the DopplerPSK package please let me know directly.
While not documented, the settings.ini file defines the Doppler center frequency in Hz.  This can be changed manually and the program restarted to "recenter" the audio carrier driving the SSB transmitter.  The default was chosen to be 2000Hz as the default since this means that the entire Doppler shift will typically run from about 1400-2600Hz with NO-84.  This should be within the IF passband of most SSB transmitters while keeping the second harmonic beyond the cutoff frequency of that same filter...if you keep things linear in the audio chain a lower frequency should be okay.  This might be helpful if your transmitter shows significant rolloff at high frequencies.
Andy K0SM/2

    On Monday, January 23, 2017 9:37 AM, Joe <nss at mwt.net> wrote:

 Yeah just getting started on this cool bird.

How well was I getting in?

I need to better my receive end.

Started with a Mini wheel and ARR Gas fet pre amp, was OK but nothing to 
scream about.

Over the weekend swapped that out to what Bob APR suggests a 2 meter GP 
3/4 wave on 70 CM and the pre-amp.

See of that works any better B4 I end up with the complex beams and 
rotors etc.

The Original Rolling Ball Clock
Idle Tyme
On 1/23/2017 8:29 AM, KO6TZ Bob wrote:
> Joe,
> There is no configuration utility built into the program.  You need to 
> simply edit the following four (4) text files in the program as needed:
> 1.        SETTINGS.INI  (this is where the settings you asked about are)
> 2.        DOPPLER.SQF (use this to add future satellites)(rarely needed)
> 3.        TLE / nasabare.txt  (VERY Important...update weekly)
> 4.        MACROS / <filename>  (configure to your liking)
> I have seen your call recently on the satellite, late in the pass for 
> me.  At present the high spin rate of NO-84 is making copy of the 
> PSK31 signals difficult.  You are there.
> Bob
> Looking for help with this program.
> All the Google results that have help guides are busted.
> I fully understand the concept of the program.
> But wonder is there a way to adjust the base start up frequency?
> Every time I have used it, I'm worried if I may be passing out of many
> peoples passbands! Even my radios for that matter on transmit. It seems
> really high all the time. I do not think it has ever been lower than 
> 2500 Hz
> Joe WB9SBD

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