On Dec 5, 2021, at 1:28 PM, Bruce KX4AZ <bruce@...> wrote:

I wonder if anyone has ever done any rough calculations using the WSPR database to do some predictive calculations around the spot numbers that could be achieved in a continuous decoding (i.e. with a KiwiSDR) versus hopping (i.e. a WSJT-x software with a single frequency receiver).

My current  'KX4AZ/T' KiwiSDR site is working reasonably well with WSPR decoding, but I don't like to tie up all 8 of the Kiwi channels with the wsprdaemon.  Recently I have had it decoding on just 4 channels (80/40/30/20).  Now and then I'll turn on a separate Airspy HF+ Discovery  "hopper" receiver for the less active WSPR frequencies...but I've always wondered about how many spots I am missing with the hopper receiver.  Seems like the WSPR database would be an excellent tool to use for constructing some predictive calculations, but I can't quite wrap my mind around the mathematics & probability calculations it would require.  And for all I know this has already been done long ago.

I wonder if anyone has ever done any rough calculations using the WSPR database to do some predictive calculations around the spot numbers that could be achieved in a continuous decoding (i.e. with a KiwiSDR) versus hopping (i.e. a WSJT-x software with a single frequency receiver).

My current  'KX4AZ/T' KiwiSDR site is working reasonably well with WSPR decoding, but I don't like to tie up all 8 of the Kiwi channels with the wsprdaemon.  Recently I have had it decoding on just 4 channels (80/40/30/20).  Now and then I'll turn on a separate Airspy HF+ Discovery  "hopper" receiver for the less active WSPR frequencies...but I've always wondered about how many spots I am missing with the hopper receiver.  Seems like the WSPR database would be an excellent tool to use for constructing some predictive calculations, but I can't quite wrap my mind around the mathematics & probability calculations it would require.  And for all I know this has already been done long ago.

I wonder if anyone has ever done any rough calculations using the WSPR database to do some predictive calculations around the spot numbers that could be achieved in a continuous decoding (i.e. with a KiwiSDR) versus hopping (i.e. a WSJT-x software with a single frequency receiver).

My current  'KX4AZ/T' KiwiSDR site is working reasonably well with WSPR decoding, but I don't like to tie up all 8 of the Kiwi channels with the wsprdaemon.  Recently I have had it decoding on just 4 channels (80/40/30/20).  Now and then I'll turn on a separate Airspy HF+ Discovery  "hopper" receiver for the less active WSPR frequencies...but I've always wondered about how many spots I am missing with the hopper receiver.  Seems like the WSPR database would be an excellent tool to use for constructing some predictive calculations, but I can't quite wrap my mind around the mathematics & probability calculations it would require.  And for all I know this has already been done long ago.

On Dec 5, 2021, at 1:40 PM, Glenn Elmore <n6gn@...> wrote:



I can't answer for 'anyone' but the short answer for myself is "no, I haven't". But I think it depends what you are after. To maximize the raw spot count with limited receiver count probably following the herd as they travel will get you more total spots. If the goal is unique spots over a day, I think following the MUF may pay off better.

By watching unique spots vs band and time of day, I try to center the 6 receivers I use on WSPR at N6GN/K2, 3/4ths of a KiwiSDR,  on where the MUF /absorption has center of mass. at a particular time of day and year.  I change the schedule in wsprdaemon several times/day.

I'm more interested in the propagation than the counts but doing this does give more data so that watching it all in conjunction with the MUF map can give insight.

On 12/5/21 11:28 AM, Bruce KX4AZ wrote:

I wonder if anyone has ever done any rough calculations using the WSPR database to do some predictive calculations around the spot numbers that could be achieved in a continuous decoding (i.e. with a KiwiSDR) versus hopping (i.e. a WSJT-x software with a single frequency receiver).

My current  'KX4AZ/T' KiwiSDR site is working reasonably well with WSPR decoding, but I don't like to tie up all 8 of the Kiwi channels with the wsprdaemon.  Recently I have had it decoding on just 4 channels (80/40/30/20).  Now and then I'll turn on a separate Airspy HF+ Discovery  "hopper" receiver for the less active WSPR frequencies...but I've always wondered about how many spots I am missing with the hopper receiver.  Seems like the WSPR database would be an excellent tool to use for constructing some predictive calculations, but I can't quite wrap my mind around the mathematics & probability calculations it would require.  And for all I know this has already been done long ago.

On Dec 5, 2021, at 4:14 PM, Bruce KX4AZ <bruce@...> wrote:

Setting up a BBAI would definitely be the best solution for me if I don't eventually add a second Kiwi, but I have the impression that would require a fair amount of effort software-wise that exceeds my current skill set -  i.e. I had just enough to get wsprdaemon running on a Pi4.  Perhaps I should do is make it my summer 2022 project, when I return to the KX4AZ/T site where the KiwiSDR is running.

Generally speaking, my goal has been to maximize the unique station counts in a 24 hour period, without tying up the KiwiSDR too much.  When I occasionally run a supplementary hopper receiver, I adjust the bands based on the time of day, to focus on what makes the most sense, i.e. at night I don't bother with 15/12/10 meters, but 630/160m are worth including.  

This thread actually belongs in the wsprbeacon forum, it occurs to me.  My interest/curiosity is in devising a mathematical algorithm to predict how many unique stations might be missed on a specific band, if a receiver is only listening for x% of the time over the course of a 24 hour period.  Essentially it becomes a cumulative probability of spotting, taking into account the the proportion of the day that the beacons are transmitting, combined with the probability that the receiver will "see" a signal of adequate S/N ratio.  My sense is that a 20% duty cycle on a single band would yield much more than 20% of the total in comparison to a continuous (100%) receiving mode.  The question is what that % value might be.  And actually, this value could be extracted from the WSPR data base if one could interrogate it in the correct way, and see how many unique spots remain if 80% of them were randomly removed from entire set of raw spots in a day.  So I should be able to answer my original question once I improve my WSPR database skills.