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San Bruno Mountain POTA: The first outing

 On the first POTA activation, the kids had hiked the mountain before, but it took ham radio to get me up there. The views ere incredible! I had no idea! Here's the view from the radio in the halfwave dipole.





Park:

San Bruno Mountain State Park (K-1196)

So far all the California POTAs have been reached via public transit. I took the SFMTA 43 to Chicago and Cordova and then hiked the rest of the way up the hill.



Radio Details:

Rockmite 20 meters using a Hamgadgets PicoKeyer. The halfwave dipole with embedded radio was about 8 feet up. This is evidenced in the picture above where I was able to get the camera very close to the radio.  


QSO/RBN spot map:


Happenings of Interest 

It seems like antenna height might not matter as much up here as I would have thought. The Rockmite and antenna were a few feet lower than on our second outing to this site, but QSOs were made further out. 


This, of course, could have also depended on the time of day, and/or the ionosheric conditions, so let's take a look at the longest contact: N4RKK 2,357 miles out. The QSO was made at 18:59 GMT (see the QSO log below.) At that time, the nearest Ionosonde in Pt. Arguello, CA produced the following ionogram:

Comparing that with a similarly timed QSO from the second outing:
VA7JCF57955918:5214058.3

which was about 800 miles out and the furthest out QSO for the day. The ionogram looks like:

The hmF2 (maxximum height of the F2 layer of the ionosphere) was a about 9 km  lower, so there's that. The 20 meter Rockmite was well within the maximum usable frequency both days.

The whole thing could also be chalked up to people further out just not being on the air the first  day. Although, you might also note that the spots for the second outing were more sparse:


That however, could also be chalked up to the memory keyer I was using that day.


QSO Log

Callsignrx RSTtx RSTTime (GMT)Frequency
KQ9L33935900:0014058.3
W6KC55957900:0014058.3
NA7US55957900:0014058.3
K7GT57959900:0014058.3
N6PF59959900:0014058.3
NZ7Q57955918:4914058.3
N6MKW55955918:5514058.3
NT6E52955918:5614058.3
N4RKK57959918:5914058.3
W7JRD52955919:2514058.3
KBTEST53955916:4214058.3 kHz


Unschooling Highlights

The 12, 10, and 8 year-old gang did meet me up there that day! They'd been up before, and so were not quite as facscinated by the views as I was. They came up on their own pastries in hand that they'd picked up when they made a bus switch. I'd already been up there for a while at that point. I love spacing our our trips like this because I get to work for a bit on my own, and they get to enjoy being out and about on their own around  town.


POTA tx QSL:



QSL rx album:





References

POTA (Parks on the Air)

Local Ionograms

https://lgdc.uml.edu/common/DIDBYearListForStation?ursiCode=PA836 (for example)


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