Hi Ron, I'm also a big fan of "frequency at the satellite" and it is one of the main reasons for using total computer control while working SSB sats. In fact, I can move the RX across the pass band and not have to worry about the uplink, it is always spot-on.
So my guess was that if both stations were computer controlled, they could be synced-up throughout the pass. However, as I'm learning here, there are more variables than meet the eye. Learning is part of the fun !
Incidentally, often times I hear two stations rag-chewing throughoutt the pass. I hear them both steadily but one sounds slightly higher/lower. Since they remain steady but I hear them differently, there must be much more going on here... (btw, I have worked HF so I understand when I am not zero-beat on the calling station's frequency)
Since you mentioned it, I have great respect for mobile stations operating SSB sats, it surely requires a great degree of dexterity and finesse. I guess I can never attempt that.
Appreciate the feedback. 73!Umeshk6vug
On Wednesday, February 6, 2019, 10:17:01 AM PST, Ronald G. Parsons w5rkn@w5rkn.com wrote:
Umesh,
A question and comment on your statement:
(b) Sometimes I hear a station calling CQ and it remains on the same frequency during successive CQs,
The method SatPC32 and HRD and others employ is keeping the “frequency at the satellite” a constant, varying your uplink and downlink frequencies as appropriate. In your statement above, do you mean by “on the same frequency” that you need not change your SatPC32 controlled frequency to remain tuned in to the CQing station? If so, then both of you are tuning to keep the “frequency at the satellite” a constant. This method is the preferred method of tuning for base stations. Mobile stations may not be able to do it. By keeping “frequency at the satellite” a constant, QSO’s with many participants can converse as easily as though they were on 20m.
Ron W5RKN
Umesh,
If you can tune around and always hear your own downlink on the correct frequency, then you are doing everything right.
73,
Paul, N8HM
On Wed, Feb 6, 2019 at 12:42 PM k6vug at sbcglobal.net <k6vug at sbcglobal.net> wrote:
Good Morning All, I'd like to understand something that seems to be happening with SSB birds.
I realize that they are two kinds of operators - one that has a computer controlled station and one that tunes manually, and I respect both types. The following observation is about two computer controlled stations working via a SSB satellite -
(a) My station is computer controlled (SatPC32 or HRD) and can hear myself on the downlink throughout the pass. I can also go up or down the pass band and still hear myself without needing to retune the uplink. It is pretty rock solid, almost like HF operation.
(b) Sometimes I hear a station calling CQ and it remains on the same frequency during successive CQs, so I'm guessing their station is also computer controlled. I can tune in and stay on their calling frequency.
(c) However, when I can respond, it seems they have to tune their downlink a bit to hear me well. So when they come back to my response, they are a bit off-frequency (about 300Hz) and sound like Mickey Mouse, until I retune the downlink to hear them well again. This keeps happening throughout the QSO.
(d) This "drifting" happens only with some stations calling CQ and not everyone.
Considering both stations are computer controlled at each end, I'm trying to understand if I'm doing anything wrong/incorrect. Learning to operate SSB sats has been humbling as well as exciting, I'd appreciate any pointers for this situation. Thanks in advance.
73! Umesh k6vug
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