Thanks for reading this. I recently installed SatPC32 from an AMSAT purchased CD onto a new WIN 7 laptop with a dual-core Pentium processor. The laptop is interfaced with a Yaesu FT-857D for 144MHZ and a Yaesu FT-897D for 432 MHZ. The interface is via a STAR-TECH Express Card serial adapter which provides 2 COM ports. The program installed properly, I updated the KEPs file, and the program controls the radios. My problem is that I can't fine tune the Doppler shift properly for my set-up. I have tried using the CAT Tuning dialog box to adjust the Downlink in order to hear my own CW signal in the downlink, then reset the downlink adjustment to zero, and then adjust the Uplink by the same frequency amount in the opposite direction, and then save the uplink calibration. I was able to get AO-7 mode B working pretty well using this technique; however, for VO-52 even when I adjust the downlink to hear myself and then change the uplink and store the change, my signal is no longer heard in the downlink... even before saving any changes, I have to continually adjust the downlink in order to hear my own signal as my signal will move out of the downlink ....I can't seem to find the correct Doppler corrected frequency pair... I thought that once I adjusted the downlink so that my signal was peaked that that would be a constant "correction" throughout the pass. Are there other adjustments that I need to try in addition to the uplink calibration? FO-29 is even harder to try and figure out than AO-7 and VO-52. Is anyone else using two Yaesu FT-817 / 857 / 897 rigs with SatPC32? If so, what do you think I am doing wrong and what are your DOPPLER.SQF data lines for AO-7, VO-52, and FO-29 (as well as any other critical settings)? I have been manually adjusting for Doppler shift for about a year on the linear satellites but I never got proficient enough to tune around the passband and answer other calls... I just parked myself on an open frequency and called until someone answered me. I can greatly appreciate the benefits of Full Doppler Tuning, I just can't seem to configure SatPC32 in order to take advantage of it! I live in central Maryland, FM-19.
Thanks for the help,
Guy Brauning
N3SCR
guyjeanbraun@comcast.net
Hi Guy and Amsat-List!
I'd like to know the answer to this too! I just recently started using twin FT-817ND's and SatPC32 as well, and notice the exact same thing -- audio drifts slightly thorughout the pass, even though I have the dopper correction set pretty close. For me, it only drifts a few hundred Hz at most, but it's still enough that I have to tweak the offset on the uplink. I'm new to SSB sats so not sure as well if there's something I'm doing wrong. I've got the time on the PC clock set within 1 second, and my lat/long within 0.01 degrees.
I'm measuring the drift just roughly based on my own audio coming back over the downlink -- unfortunately as I've called CQ on FO-29 and VO-52 the last few evening's passes (0100-0500 UTC), no one else has been on the sats for a direct QSO! My own audio comes back nice and clear (even out to 5 degrees elevation) so it's not a reception problem, as far as I know.
Any help for those of us new to the satellites would be appreciated!
Thanks,
Dave KB5WIA CM88 Northern California 2xFT817-ND, Elk Log-Periodic, MH-72 Duplexer, Samsung Netbook running SatPC32.
Is anyone else using two Yaesu FT-817 / 857 / 897 rigs with SatPC32? If so, what do you think I am doing wrong and what are your DOPPLER.SQF data lines for AO-7, VO-52, and FO-29 (as well as any other critical settings)?
participants (2)
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David Palmer -
Guy Brauning