Hello Dany,
Try perhaps to check if your results match others tracking applications.
I do use http://amsat.org.ar/pass or http://amsat.org.ar/pass.exe with wispdde driver or HDSDR.
Using last 2 combinations, I follow LO-19 constant carrier receiving CW and software follows right on frequency, using either an FT-736 or FT-897.
To calculate Xmt & Rcv Dopplers, I take into account instant satellite velocity related to user ground station, always using the latest TLEs.
We can share formulas to calculate both Dopplers if that helps.
Best 73, LU7ABF, Pedro
On Mon, Oct 30, 2017 at 6:53 PM, Dani EA4GPZ daniel@destevez.net wrote:
Hi all,
A few days ago I have transmitted and recorded a (low-power) FT8 signal through the FO-29 linear transponder to test some Doppler correction algorithms I'm developing (see http://destevez.net/2017/10/wsjt-x-and-linear-satellites-part-ii/)
After Doppler correction, I'm left with a linear frequency drift both in my downlink signal and in the satellite CW beacon. However, the drift rate of my signal and the beacon are different. Specifically, my signal drifts 1.26 times faster than the beacon. I suspect that this drift is due to one of the local oscillators in FO-29.
To understand this better, I need to look at a block diagram of the FO-29 linear transponder. The best I've found is this:
http://www.jarl.org/English/5_Fuji/systeme.gif
However, I need something similar to this:
https://funcubetest2.files.wordpress.com/2010/11/funcube_ rf_board_block_diagramv2-1_pa3weg_open-1.pdf
Since I need to see the frequencies of all the local oscillators involved in the transponder and CW beacon.
Is there a more detailed block diagram for FO-29 or does anyone know something about this information?
73,
Dani EA4GPZ. _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb