[amsat-bb] PSAT2 SSTV/telemetry intervals?

[Tomáš Urbanec]

Hi Hans,
as you can see from documents mentioned above, the timing depends on 
battery voltage, which selects one of four operating modes, but 
basically we are lucky to be in highest mode A which means every 2 
minutes PSK telemetry and every second telementry frame is twice longer 
and contains also SSTV picture. All of this is overdriven by sunwire 
logic signal going low. That means no transmission on UHF downlink after 
going in eclipse for maximum of 30 minutes (failsafe timer).
If you will transmit on uplink and your signal will be sensed, it will 
switch on the downlink for the next 20s.
          Tomas OK2PNQ and Ales OK2ALP

Dne 6.7.2019 v 15:15 Hans BX2ABT via AMSAT-BB napsal(a):
> Thanks for the link, I hadn't seen that page, yet.
> 
> As for 2m: I have a nasty local case of interference here which wipes 
> out 145.825 in most directions (local electronic billboard), so I'm not 
> active with APRS.
> 
> BTW, what do you mean by NARROW-FM? I take it that it is the deviation 
> of the FM signal, with narrow being 2.5 kHz, right?
> 
> 73 de Hans
> 
> BX2ABT
> 
> 
> On 07/06/2019 09:42 AM, Scott via AMSAT-BB wrote:
>> There is quite a bit of detail on the possible modes of PSAT-2 
>> operation at:
>>
>> https://github.com/alpov/PSAT-2/blob/master/README.md
>>
>> ... so far, I've seen both PSK31 and SSTV in the 70cm downlink.  However,
>> at such low elevations I am not getting enough signal to determine 
>> exactly
>> what the current pattern of operation is.
>>
>> However, on the 2m downlink (145.825), the activity has picked up each
>> night as the rising elevation makes PSAT-2 available to more folks.  
>> Please
>> remember to transmit in NARROW-FM mode and if your radio has CAT control
>> and you can doppler-correct your uplink, better yet.
>>
>> -Scott,  K4KDR
>>
>> ==========================
>>
>> On Fri, Jul 5, 2019 at 9:28 PM Hans BX2ABT via AMSAT-BB 
>> <amsat-bb at amsat.org>
>> wrote:
>>
>>> Nobody knows? Here in east Asia some other hams are asking the same. We
>>> have good passes late at night (1400 UTC), but no PSK31 or SSTV seen at
>>> all. --Hans BX2ABT
>>>
>>>
>>> On 07/04/2019 10:48 PM, Hans BX2ABT via AMSAT-BB wrote:
>>>> Hello all. At what intervals do the SSTV and PSK31 telemetry get
>>>> broadcast? Just had another good pass, saw some SSTV in the beginning,
>>>> but until LOS not a single blip heard. Same yesterday. What gives? 73
>>>> de Hans
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>>
> 
> _______________________________________________
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