I just had a very noisy 6 degree max pass here in VT. There was nobody in the footprint on L Band so I tested nominal frequency for the uplink.
This time the nominal was ~ 8.5 kHz high. 1267.3585
More testing is needed, especially with lower power to fine tune.
Mike
Yes, definitely need to shoot a little high on the L-band uplink. I was running it about 10khz high, but it seemed to have some tolerance for being off by a few. Made contact on the 04:47z pass with Patrick WD9EWK, and also heard AD5MT, but couldn't complete the contact. Manual tuning of the FT-736R uplink, watching Gpredict's display, with computer control of the FT847 downlink and antenna rotisserie. That's the first contact on L-band since, um, AO-51? Nice to know it still all works! Now I need to figure out how to get Gpredict to run both radios...
Stations heard have a "distant" sound to them - kind of hard to describe, and not something I've heard on other satellites. I think the lower part of the audio frequency response may not be as strong as the upper part. Also, the audio was kind of quiet overall (comparing to the unsquelched hash). {shrug} Certainly not a big problem, however you do have to listen carefully. Headphones required.
Greg KO6TH
Mike Seguin wrote:
I just had a very noisy 6 degree max pass here in VT. There was nobody in the footprint on L Band so I tested nominal frequency for the uplink.
This time the nominal was ~ 8.5 kHz high. 1267.3585
More testing is needed, especially with lower power to fine tune.
Mike
Mike,
I confirm that the uplink frequency on L-mode is about 9kHz high. I made a QSO with ZS2BK, my good friend Andre yesterday and also check same on the previous pass of AO-92, being in the middle of the Indian Ocean and having the SAT for myself to test during the whole passage it was easy to confirm same.
On the other hand I believe that the SAT is very sensitive on L-mode, to explain I was made to understand that one needs about 100W EIRP to have reliable com on this bird on this mode, I was able to trigger it with about 70W EIRP as from horizon (ele. 0 deg.), and ZS2BK in spite some fading was crystal clear sometimes with about only 24W EIRP. We need a few more passes to determine the exact requirement and will do so this side.
Not to mentioning the U/V mode which is superb, 3 local HAM’s in 3B8 were able to make a QSO with Baofeng’s last Wednesday...
I hope my feedback is constructive.
73
Jean Marc (3B8DU)
On Feb 5, 2018, at 4:21 AM, Mike Seguin [email protected] wrote:
I just had a very noisy 6 degree max pass here in VT. There was nobody in the footprint on L Band so I tested nominal frequency for the uplink.
This time the nominal was ~ 8.5 kHz high. 1267.3585
More testing is needed, especially with lower power to fine tune.
Mike
73, Mike, N1JEZ "A closed mouth gathers no feet" _______________________________________________ Sent via [email protected]. 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
Hi Jean Marc,
Tnx for the info. Yes, this is very helpful. Lowering uplink power helps tremendously in finding the ideal frequency.
Reports so far all seem to be in substantial agreement.
Mike
On 2/5/2018 1:03 PM, Jean Marc Momple wrote:
Mike,
I confirm that the uplink frequency on L-mode is about 9kHz high. I made a QSO with ZS2BK, my good friend Andre yesterday and also check same on the previous pass of AO-92, being in the middle of the Indian Ocean and having the SAT for myself to test during the whole passage it was easy to confirm same.
On the other hand I believe that the SAT is very sensitive on L-mode, to explain I was made to understand that one needs about 100W EIRP to have reliable com on this bird on this mode, I was able to trigger it with about 70W EIRP as from horizon (ele. 0 deg.), and ZS2BK in spite some fading was crystal clear sometimes with about only 24W EIRP. We need a few more passes to determine the exact requirement and will do so this side.
Not to mentioning the U/V mode which is superb, 3 local HAM’s in 3B8 were able to make a QSO with Baofeng’s last Wednesday...
I hope my feedback is constructive.
73
Jean Marc (3B8DU)
On Feb 5, 2018, at 4:21 AM, Mike Seguin [email protected] wrote:
I just had a very noisy 6 degree max pass here in VT. There was nobody in the footprint on L Band so I tested nominal frequency for the uplink.
This time the nominal was ~ 8.5 kHz high. 1267.3585
More testing is needed, especially with lower power to fine tune.
Mike--
73, Mike, N1JEZ "A closed mouth gathers no feet"
participants (3)
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Greg D -
Jean Marc Momple -
Mike Seguin