Nightly report of comparison kfs - kph on 80m to copy JA's in contest


ON5KQ
 

Hi Glenn,

Exactly.

When you have a very quit location and a really well working omni-directional antenna the only way to get better wspr-reception reports is:

- directional antennas......   AND (very important!)

- many of them in different directions 

with only one directional antenna you will have less spots than with the simple omni-directional antenna....

Only in that case it makes sense to me, to use more that one receiver on one frequency. Although it is clear that more receivers increase the number of spots due to statistical reasons...

As I do not have this directional antenna set-up at the moment I use only one receiver per band at the moment (with exceptions during antenna tests)


May be, I will NOT join coming Wednesday - we are planning a full day cycling tour and I might not be back in time for the meeting....

So please inform the group...

Ulli


Ulli,
An interesting comparison, thanks for sharing it.  Because of it, I took a look at Grafana to compare KPH/TCI-530 with KFS/best_of_all_merged_antennas  on 80m during that same time, it looks like this:


What I find interesting is that KPH and KFS are almost exactly the same on WSPR during this time of day - and actually overall. They are closer than the perhaps 6 dB of SNR improvement your JA CW captures show.  This seems to me to add support your hypothesis that the extra directivity, the F/B of KFS antenna is helping, but of course only in that direction. On average, considering all WSPR signal directions they have similar performance.
I think this rather confirms what we knew - directive antennas can be useful when used appropriately but they aren't a solution in every situation.  No doubt if there were noise sources over the pacific (maybe a really noisy SMPS at Rob's AI6VN/KH6 site (:>)  )  things might be different.



Glenn Elmore
 

Ulli,
An interesting comparison, thanks for sharing it.  Because of it, I took a look at Grafana to compare KPH/TCI-530 with KFS/best_of_all_merged_antennas  on 80m during that same time, it looks like this:


What I find interesting is that KPH and KFS are almost exactly the same on WSPR during this time of day - and actually overall. They are closer than the perhaps 6 dB of SNR improvement your JA CW captures show.  This seems to me to add support your hypothesis that the extra directivity, the F/B of KFS antenna is helping, but of course only in that direction. On average, considering all WSPR signal directions they have similar performance.
I think this rather confirms what we knew - directive antennas can be useful when used appropriately but they aren't a solution in every situation.  No doubt if there were noise sources over the pacific (maybe a really noisy SMPS at Rob's AI6VN/KH6 site (:>)  )  things might be different.


ON5KQ
 

Great, that kph is receiving again with the kiwi's...
I thought I use the Japanese CW contest to make a screenshot of kfs (NWest antenna) and compare it with the TCI 530 at kph
I know that this is not a fair comparison - for your information - both TCI-530s at kfs and kph were very similar with almost no difference in reception.

However if you already have a real good receiver, how much you need to invest more, to improve the reception further ? This gives some impression...

As usual, the 80m band is very noisy at 3h20 local California time....
So to hear the JA-stations in 80m CW you need some attenuation of the QRN (from the land side) and good gain over the pacific...
The directional LPDAs at kfs offer both....

Here is the difference - I attach two high resolution screenshots, so you can really compare the details.
All stations calling above 3510kHz are JA's in the contest calling. You can see, that just a tiny bit better reception makes the difference in this band propagation...
Most stations were difficult to copy at kph, due to the noise...
The noise situation was not much better at kfs, however the net gain into the northern Pacific make the difference - the visible stations were very easy to copy... some stations could be copied which were not at all readable at kph...

Conclusion: It is very worthwhile to have large directional antennas to the pacific from west-coast US-stations. Especially as the distances are very long, low elevation take-off antennas should be used...

Ulli, ON5KQ
P.S.: screenshots are taken exactly at the same time...