Observation 13018443: Foresail-1p (98467)

[auk]

Regarding Observation 13018443 …

It’s considered “failed” but the waterfall and audio is there?

[bali]

ussualy its false failed, caused when network is bottleneck, so late post the obs result

[fredy]

@bali

ussualy its false failed, caused when network is bottleneck, so late post the obs result

That’s not true, when watefall, audio file or data are uploaded even after a late post the status changes from fail to unknown.

The case here is that observation duration is 11min and 20sec but the audio duration is 4min and 13sec. When the audio file duration has more than one minute difference with the scheduled duration the observation automatically marked as failed.

@https://community.libre.space/t/observation-11595496-noaa-9-15427/13299/2

Why audio can have sorter duration?

The short audio duration means usually that there are lost samples, this happens:

1. When the CPU can not process all the samples that are coming from the SDR aka overflow. This is visible in the logs of client noted with several big O’s, you may need to change the logs level to see them.
2. When there is underflow, in other words SDR doesn’t provide the right amount of samples to maintain the sample rate. This is visible in the logs of client noted with several small o’s, you may need to change the logs level to see them.

---

For the first case, which is the most usual, there can be several reasons, below are some of them we have experienced:

1. CPU Temperature:
   In this case increased CPU temperature forces CPU to work at lower frequency to decrease the temperature, this lower frequency isn’t enough to allow processing of all the samples. Usually a CPU heat sink or fan or better ventilation can improve/fix the issue.
2. Power Supply:
   In this case the power supply isn’t enough to support CPU high frequency. Similarly to the temperature issue, the CPU works at lower frequency causing loss of samples. This can be solved by changing the power supply, after making sure that the current one doesn’t offer the necessary power.
3. High Sample Rate:
   In this case the sample rate of the SDR is set to a very high value, such that the CPU can not process. Solution is to set a lower sample rate.

[bali]

@fredy

When the audio file duration has more than one minute difference with the scheduled duration the observation automatically marked as failed

answer my failed obs too

thank you!

[pe2bz]

May I ask why the sample rate for SDR is choosen to be such a strange value instead of 2.048 ?

[bali]

i just test it, follow other station that give good result. but look not too good result on my station

[auk]

Hello,

Because of this topic : Observation 12326506: WEIRD WATERFALL - #11 by PE0SAT

I was told to reduce the rate to avoid a recuring issue with wrong SDR output.

[bali]

@auk

I was told to reduce the rate to avoid a recuring issue with wrong SDR output.

aha. i try follow sample rate @auk groundstation @pe2bz . look at this obs. very good result

[auk]

Please bear in mind however that I recently put the min/max dB manually to try to see a the signals better. Waterfall is not automatic on this one.