Just a quick note. 

My partner and I went to see Robot Dreams with the 11 and 9 year olds about a week and a half ago. First, the movie is awesome! It stays almost true to the book in that there are very, very few words at all. More in the movie than there ever were in the book, but still. The whole thing was a lot of fun and I highly recommend it.

After the movie, my partner and I went off to do errands in one direction, the 11 and 9 year old headed  towards the house on BART. And! Guess what?

They ran into their older sib on the bus home. There routes coincidentally linked up for the last leg and they hopped on the sam bus she was on. About a stop later, they all realized it.

Public transit and independent kids are pretty awesome! We got to do our errands. The kids got to go do what they wanted, and they ran into each othere anyway! Without transit, I doubt we could have even seen the movie because we'd have been making camp pickups and whatnot. Woooo MUNI and BART!

 On one of the most interesting radio days of our recent camping trip, Project TouCans made QSOs with Australia, Japan, Columbia, and Argentina, all on the same day! The QSOs to Japan and Australia were made in the middle of their night. The Japan, Australia, and Columbia QSOs were all made in a sixteen minute window beginning with VK3YV at 12:40 UTC.

What was the Propagation Mode?

Chordal Modes Introduced with Villard

Carter Manny Jr. worked with Stanislaw. Here's his Chicago Tribune obituary.

Finding Our Antipodal Point

To find the anitpoidal point, we can follow our longitude over the North (or South for that matter) where it will become the same longitude minus 180 degrees, or pi radians if that's the unit you prefer. You can see this in the diagram below where our longitude of about -107 degrees traced over the pole becomes about 73 degrees.

Meanwhile, our latitude above the equator will be used to find the same number of degrees below the equator:

37.82275 becomes -37.82275.

More precisely, we get 

37.822754°N 107.717935°W -> 37.822754°N 72.282065°E

And our anitpodal is shown below near the 70 degrees East label.

Pretty excellent discussion of anitpodal points.

Conclusions for the moment

 The fact that KO6BTY and I both made our POTA contacts with Japan while it was still very much nighttime in Japan, fascinates me. Here's what my QSO with JG0AWE looked like with respect to the night sky and the grey line.

 The gang and I made our first QSO with Australia this week!

The QSO came bundled with two other DX contacts made with Project TouCans—all in a 16 minute window—which I'll write about soon. Our camping site is nestled below Anvil Mountain to the East and across the Million Dollar Highway from South Mineral Springs, about two miles north of Silverton, CO. We're surrounded by peaks on all sides. Bear Mountain peak is framed in my pictures of the rig.

Project TouCans was probably 20 feet up in its dipole. This turned out to be difficult to show in photographs with the proper perspective. I finally decided to make a gif of different zoom levels of a single photo. The picture below starts out focused on Bear Mountain Peak and then zooms out to include the rig and the ground outside my partner's and my tent.

You can see the Bluetooth transmitter that brings the head phone audio down to the ground hanging from the bottom of the rig.

The campsite is gorgeous and almost completely bug free. I managed to make it out on one hike. Tawnse—the nine year-old—our puppy, and I were treated to views like this

That brings us to the circumstances of the QSO with VK3YV, the first DX QSO of that morning. Here's our campsite from a way's out showing the F2 skip path (estimated using real-time data from the Boulder, CO ionosonde), as well as the path of the QSO along the ground. 

So, with all those mountains in the way, how did we talk to Australia?

Project TouCans threaded the valley to the west of our campsite! Check this out!

I'll leave you with the map of the QSO so you can trace along the path at your leisure. Use the time control in the lower left corner or the slider along the bottom of the map to locate the QSO at 12:40 UTC. From there, you can zoom in and out using a mouse center-button wheel. You can also tilt by holding down the control key, and then moving the map using the left mouse button.

Update

Due to a bug in the ionosonde code that I'd immediately introduced, the F2 layer height was not 307 km as shown in the diagram above. It was in fact, 235 km over Hawaii which had data at the time, (Boulder, CO in fact did not), and which was closer to the middle of the QSO path as well. The difference in F2 height resulted in the first mountain intersection that used to look like this

with the incorrect data looking like this with the new F2 height data

References

Ionosonde Data

This was made possible with data collected by 

Reinisch, B. W., and I. A. Galkin, Global ionospheric radio observatory (GIRO), Earth, Planets, and Space, 63, 377-381, doi:10.5047/eps.2011.03.001, 2011.

• http://spase.info/SMWG/Observatory/GIRO

 POTA activation from Silverton in twenty-one minutes!

Project TouCans had one of its highest ever antenna placements.

I'm loving the, (very real), yet very sci-fi look of what's going on with the F2 skips from this rig at this location

Turns out, it's line of sight between mountains from here

QSO Map

Here's the map you can steer around in on your own! Remember, click play in the lower left hand corner, then move the time slider all the way to the left. You'll be able to see all the QSO paths and their F2 skip paths (based on Boulder, CO ionosonde data at the time of the QSO.) If you click play again, you'll be able to see how the QSOs played out over time.

Notes

Difference in Altitude

I'm still working through getting the F2 traces to routinely emit from the ground. This time, Google Maps said the elevation here was 2982.468 m, but Cesium is happier with 2947.468 m, co about 35 meters lower than expected. Even then, we're not on the ground

SQL Query

select

  tx_lng,

  tx_lat,

  rx_lng,

  rx_lat,

  rm_rnb_history_pres.timestamp,

  rm_rnb_history_pres.dB,

  rm_rnb_history_pres.Spotter,

  haversine(tx_lat, tx_lng, rx_lat, rx_lng) as total_path,

  gis_partial_path_lat(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lat,

  gis_partial_path_lng(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lng,

  id,

  strftime('%Y%m%d', timestamp) as date,

  strftime('%H%M', timestamp) as time,

  'US-4399' as park,

  'KD0FNR' as call,

  'BC840' as ionosonde,

  2947.468 as elev_tx

from

  rm_rnb_history_pres

where

  dB > 100

  and timestamp > '2024-05-29'

  and timestamp < '2024-05-30'

order by

  rm_rnb_history_pres.timestamp desc

SQL Query for RBN and QSOs

Due to a bug/oversight in the system, I have to run with tx location coordinates set in the query when I want to include RBN spots, so here's that query

select

  -107.7179358 as tx_lng,

  37.8227611 as tx_lat,

  rx_lng,

  rx_lat,

  rm_rnb_history_pres.timestamp,

  rm_rnb_history_pres.dB,

  rm_rnb_history_pres.Spotter,

  haversine(tx_lat, tx_lng, rx_lat, rx_lng) as total_path,

  gis_partial_path_lat(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lat,

  gis_partial_path_lng(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lng,

  id,

  strftime('%Y%m%d', timestamp) as date,

  strftime('%H%M', timestamp) as time,

  'US-4408' as park,

  'KD0FNR' as call,

  'BC840' as ionosonde,

  2947.468 as elev_tx

from

  rm_rnb_history_pres

where

  timestamp > '2024-05-29'

  and timestamp < '2024-05-30'

order by

  rm_rnb_history_pres.timestamp desc

References

Ionosonde Data

This was made possible with data collected by 

Reinisch, B. W., and I. A. Galkin, Global ionospheric radio observatory (GIRO), Earth, Planets, and Space, 63, 377-381, doi:10.5047/eps.2011.03.001, 2011.

• http://spase.info/SMWG/Observatory/GIRO

 We got to camp a bit more in the middle of nowhere than we usually do while traveling across Utah last weekend. My partner found the Burr Trail Scenic Byway. I've looked for a route across southern Utah for the last several years, but had somehow missed this really nice, well-paved, little road.

We camped at the foot of an East-facing cliff, and the QSO map for the POTA reflected that fact pretty nicely:

How? How had the signal cleared the cliff and skipped out to Perris, CA?

Using data from the Boulder, CO ionosonde, at the time Project TouCans was spotted in California, the F2 layer skip is modeled in the gif below. Note that it clears the mesa, (just barely.)

The other skip off to the Southeast was headed to the Cayman Islands. All of the skewing around is to convince myself that the the F2 path lines up with the path to the spotting station. You'll notice that there's a slight elevation offset that needs to be fixed.

More Notes on the POTA

I blew out my knee a bit sitting on the ground outside the tent for a three hour podcast interview on Friday night, consequently, the gang did most of the station set up including deploying Project TouCans in its dipole. Throughout that process, the family pup kept me company

When the gang were done, we had what, for Project TouCans, was a fairly typical antenna height of about five feet over the ground

One really interesting aspect of this POTA was that I didn't have the ability to Internet spot myself. Frankly, I wasn't sure it was going to work out at all, and for the longest time from about 00:02 GMT 24-05-27 till 13:50 GMT on the same day, it didn't. (Yes, I was asleep for most of that time with the rig turned off.) And then! Thanks—I think—to a few neighboring POTA stations, ops started to realize that TouCans was there! It may have also helped that my first QSO with WI5D was a bit of a rag chew.

Also, while hanging out on the cliff, the gang found an interesting mineral/quartz/mica/I don't know sample of rock. It was flat, broke easily, and contained pockets of crystals that were translucent. Any ideas what this might be?

For the moment, I'll leave you with this map of all the spots and QSOs for the POTA over the course of the evening, and into the next morning. Click play, then move the time slider all the way back to the left to see all the spots and QSOs with their associated F2 skips at once. Then, you can hit play to see how it all unfolded. (Keep in mind, the overnight nothingness is included in the map. You may want to skip over that.)

As a final note, while I'm waiting for all the F2 data to come back, I've been trying to convince the gang that the F2-height datastream from the Boulder, CO ionosonde 

is in fact entered manually by a room of accountants not unlike those in John Wick, but to no avail. I guess they're just digital natives :) 

Ah! And credits to where the ionosonde data actually is coming from

This was made possible with data collected by 

Reinisch, B. W., and I. A. Galkin, Global ionospheric radio observatory (GIRO), Earth, Planets, and Space, 63, 377-381, doi:10.5047/eps.2011.03.001, 2011.

• http://spase.info/SMWG/Observatory/GIRO

 Here's the query I'm using for Burr Trail

============================================

select

  tx_lng,

  tx_lat,

  rx_lng,

  rx_lat,

  rm_rnb_history_pres.timestamp,

  rm_rnb_history_pres.dB,

  rm_rnb_history_pres.Spotter,

  haversine(tx_lat, tx_lng, rx_lat, rx_lng) as total_path,

  gis_partial_path_lat(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lat,

  gis_partial_path_lng(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lng,

  id,

  strftime('%Y%m%d', timestamp) as date,

  strftime('%H%M', timestamp) as time,

  'US-4399' as park,

  'KD0FNR' as call,

  1770.829467773438 as elev_tx

from

  rm_rnb_history_pres

where

  dB > 100

  and timestamp > '2024-05-27'

  and timestamp < '2024-05-28'

order by

  rm_rnb_history_pres.timestamp desc

=======================================================

At some point I'll add an ionosonde field using this map for each QSO. For the Boulder, CO ionosonde, the query will look like

=========================================================

select

  tx_lng,

  tx_lat,

  rx_lng,

  rx_lat,

  rm_rnb_history_pres.timestamp,

  rm_rnb_history_pres.dB,

  rm_rnb_history_pres.Spotter,

  haversine(tx_lat, tx_lng, rx_lat, rx_lng) as total_path,

  gis_partial_path_lat(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lat,

  gis_partial_path_lng(tx_lat, tx_lng, rx_lat, rx_lng, 200) as el_lng,

  id,

  strftime('%Y%m%d', timestamp) as date,

  strftime('%H%M', timestamp) as time,

  'US-4399' as park,

  'KD0FNR' as call,

  'BC840' as ionosonde,

  1770.829467773438 as elev_tx

from

  rm_rnb_history_pres

where

  dB > 100

  and timestamp > '2024-05-27'

  and timestamp < '2024-05-28'

order by

  rm_rnb_history_pres.timestamp desc

limit 1

====================================================================

The extra ionosonde field works!!! 

References

Ionosonde Data

 The F2 skip traces in Cesium have looked a bit odd:

It's because they're starting from sea level, not the altitude of the station.... I think... What follows are somewhat random development notes.

Relative to Ground: True, Alt: 0

Almost!!!

Relative to Ground: true, elevation: 1770.829467773438

I got the more accurate elevation from the elevation plugin using:

{{ tx_lat }},{{ tx_lng }}|{{ rx_lat }},{{ rx_lng }}

So, it seems like the correct altitude in this case should be 0. (Start the line on the ground.) But, if I put in zero for altitude, I get the result shown above

 The recent pair of QSOs to Japan from Project TouCans from Great Basin National Park has me wondering about F2 layer ionospheric skip propagation again.

I got our F2 skips working for CZML. Here's a look at the skip path for JJ2JQF de KO6BTY. Notice the Earedson ionosonde is almost right in the middle

Here's the map to take a look at 

Note that the path goes for a little while underground. However, Hugyens:

Query for JJ2JQF

Query for JG0AWE

And the data went away!

Notice that the table on the left isn't there. Take a look at the JJ2JQF data (two days later) for comparison

Sources of Ionosphere and specifically F2 data from around the world

New to me: Mirrion ionosonde images from NOAA. I haven't seen this page before. Not super-useful to me because it points at images, not numeric data.

Lowell Digisonde Station list: Handy map of where stations exist.

CZML and HTML style comments

Accessing data via URL

We use an address like this

https://lgdc.uml.edu/common/DIDBGetValues?ursiCode=PA836&charName=hF2,hmF2&fromDate

to pull in ionosonde data. To access different stations, you need different ursiCode values, (one per station.) These can be found at https://www.digisonde.com/ under the URSI column.

This URL worked great in the browser, but thanks to this issue, stumbled a few times in the czml plugin's calls to get_f2m.

References

Ionosonde Data

 Today KO6BTY made a QSO to Japan from Great Basin National Park!!!

Just like last year!

I was using a bit more power this year. Project TouCans is running somewhere between 3 and 5 Watts at the moment.

He caught me just before the gang go the oatmeal ready, (we're camping on the edge of Great Basin National Park), On top of that, a RBN station in Japan had spotted Project TouCans about half an hour before. There wasn't a grey line between our locations, so I'm curious about what was going on, but delighted to have made the QSO!

Here's the activation in Cesium so you can see where the sun was in relation to the QSO. The QSO takes place at 14:49 near the end of the animation.

 Washi tape to the rescue again!

Tuesday morning, with Project TouCans working better that it had in days, I noticed that the ends of our stranded wire antenna had begun to fray out. I grabbed a roll of washi tape from my pocket, (who doesn't take washi tape on a radio outing?), and a few minutes later, voila

 The band's looking alright to Project TouCans this morning!

spotter	● spotted	distance mi	freq	mode	type	snr	speed	time	seen
K3PA-1	KD0FNR/6	1360 mi	14057.4	CW	CQ	8 dB	18 wpm	1244z 17 May	3 minutes ago
ND7K	KD0FNR/6	385 mi	14057.3	CW	CQ	7 dB	18 wpm	1244z 17 May	3 minutes ago
W6YX	KD0FNR/6	207 mi	14057.4	CW	CQ	13 dB	17 wpm	1244z 17 May	4 minutes ago
W1NT-2	KD0FNR/6	2601 mi	14057.4	CW	CQ	8 dB	17 wpm	1243z 17 May	5 minutes ago
W1UE	KD0FNR/6	2579 mi	14057.4	CW	CQ	4 dB	18 wpm	1242z 17 May	6 minutes ago
KO7SS	KD0FNR/6	533 mi	14057.3	CW	CQ	6 dB	18 wpm	1239z 17 May	8 minutes ago
TI7W	KD0FNR/6	2746 mi	14057.4	CW	CQ	8 dB	17 wpm	1238z 17 May	10 minutes ago
AC0C-1	KD0FNR/6	1376 mi	14057.4	CW	CQ	4 dB	17 wpm	1237z 17 May	10 minutes ago
ZF9CW	KD0FNR/6	2633 mi	14057.3	CW	CQ	9 dB	18 wpm	1237z 17 May	11 minutes ago
VE6WZ	KD0FNR/6	1154 mi	14057.2	CW	CQ	11 dB	18 wpm	1236z 17 May	12 minutes ago
W6YX	KD0FNR/6	207 mi	14057.4	CW	CQ	12 dB	18 wpm	1234z 17 May	14 minutes ago
K5TR	KD0FNR/6	1272 mi	14057.4	CW	CQ	5 dB	17 wpm	1234z 17 May	14 minutes ago
ND7K	KD0FNR/6	385 mi	14057.3	CW	CQ	12 dB	18 wpm	1234z 17 May	14 minutes ago
K3PA-1	KD0FNR/6	1360 mi	14057.4	CW	CQ	10 dB	17 wpm	1233z 17 May	14 minutes ago
W1NT-2	KD0FNR/6	2601 mi	14057.4	CW	CQ	4 dB	17 wpm	1232z 17 May	15 minutes ago
W4KAZ	KD0FNR/6	2261 mi	14057.3	CW	CQ	6 dB	18 wpm	1232z 17 May	16 minutes ago
K6FOD	KD0FNR/6	118 mi	14057.4	CW	CQ	4 dB	17 wpm	1231z 17 May	16 minutes ago
W3OA	KD0FNR/6	2145 mi	14057.4	CW	CQ	4 dB	17 wpm	1231z 17 May	16 minutes ago
ZF9CW	KD0FNR/6	2633 mi	14057.4	CW	CQ	6 dB	17 wpm	1230z 17 May	18 minutes ago
KA7OEI	KD0FNR/6	569 mi	14057.4	CW	CQ	16 dB	18 wpm	1229z 17 May	19 minutes ago
KO7SS	KD0FNR/6	533 mi	14057.4	CW	CQ	6 dB	18 wpm	1228z 17 May	20 minutes ago
VE6WZ	KD0FNR/6	1154 mi	14057.3	CW	CQ	12 dB	17 wpm	1226z 17 May	22 minutes ago
N0OI	KD0FNR/6	161 mi	14057.4	CW	CQ	7 dB	17 wpm	1225z 17 May	23 minutes ago
W6YX	KD0FNR/6	207 mi	14057.4	CW	CQ	12 dB	17 wpm	1224z 17 May	24 minutes ago
ND7K	KD0FNR/6	385 mi	14057.4	CW	CQ	8 dB	18 wpm	1224z 17 May	24 minutes ago
AC0C-1	KD0FNR/6	1376 mi	14057.4	CW	CQ	7 dB	17 wpm	1223z 17 May	24 minutes ago
K3PA-1	KD0FNR/6	1360 mi	14057.4	CW	CQ	12 dB	18 wpm	1223z 17 May	24 minutes ago
WA7LNW	KD0FNR/6	348 mi	14057.4	CW	CQ	6 dB	17 wpm	1223z 17 May	25 minutes ago
K5TR	KD0FNR/6	1272 mi	14057.4	CW	CQ	6 dB	18 wpm	1223z 17 May	25 minutes ago
TI7W	KD0FNR/6	2746 mi	14057.4	CW	CQ	5 dB	17 wpm	1223z 17 May	25 minutes ago
KA7OEI	KD0FNR/6	569 mi	14057.5	CW	CQ	28 dB	18 wpm	1218z 17 May	30 minutes ago
W8WWV	KD0FNR/6	2078 mi	14057.4	CW	CQ	5 dB	18 wpm	1218z 17 May	30 minutes ago
VE6WZ	KD0FNR/6	1154 mi	14057.4	CW	CQ	11 dB	21 wpm	1215z 17 May	33 minutes ago
K7CO	KD0FNR/6	530 mi	14057.5	CW	CQ	2 dB	21 wpm	1215z 17 May	33 minutes ago
W6YX	KD0FNR/6	207 mi	14057.5	CW	CQ	18 dB	20 wpm	1213z 17 May	34 minutes ago
ND7K	KD0FNR/6	385 mi	14057.4	CW	CQ	3 dB	21 wpm	1213z 17 May	34 minutes ago
K3PA-1	KD0FNR/6	1360 mi	14057.5	CW	CQ	17 dB	20 wpm	1213z 17 May	34 minutes ago
WA7LNW	KD0FNR/6	348 mi	14057.5	CW	CQ	7 dB	20 wpm	1213z 17 May	35 minutes ago
AC0C-1	KD0FNR/6	1376 mi	14057.5	CW	CQ	13 dB	20 wpm	1213z 17 May	35 minutes ago
K5TR	KD0FNR/6	1272 mi	14057.5	CW	CQ	9 dB	21 wpm	1213z 17 May	35 minutes ago

 The rig is back up and running.

I made two QSOs last night from the home QTH with a lot of noise! They were to KA6JLT in Reno, NV and and WN1Z in Susanville, CA from here in San Francisco.

This time, we did not measure the power out of Project TouCans. I suspect our several decades old Radio Shack power meter has given up the ghost, or there's something wonky in one of the cheapo connectors from Amazon.

As a side note, the radio is much quieter and works better when the RF output leads are soldered directly to the banana binding posts at the top of the rig that the antenna attaches to.

Side, side note. KO6BTY and I need to keep a slightly cleaner workbench. The rig sparked and vaporized a stray shred of wire yesterday once when we powered it up.

 Reading up on the Tuna Topper and funding for amateur radio projects

Since we're now blowing FETs on Project TouCans, and KO6BTY and I are giving a presentation about the rig to the San Francisco Amateur Radio Club on Friday, I've been reading up on amplifier theory. I really like this article explaining how the different classes of amplifiers work except for the horribly gendered  first paragraph.

In other reading news, (it's finals week for KO6BTY and I'm getting ready for our camping trip, so mostly all I've had time to do over the last few days is read), Simon Willison pointed out that the Amateur Radio Digital Communications group has grants for advancing the usage and technology of amateur radio. Here are some examples of what's been funded.

And finally, here's a link to the article that taught me how to increase power output on the Tuna Topper by upping the bias voltage. It's an even more cool article now that I know how the calls A Tuna Topper amplifier actually works.

To wrap things up, we're hoping to get TouCans back up and running today. Here's a nighttime look at the rig from the ground. The white object is the 10 meter rig's balun.

Or, how I learned to miss hard resetting RFI.

Up until about a week and a half ago, Project TouCans and the Flying Rockmite before it had never blown a final amplifier transistor. Our good fortune with transistors was caused in large part not by any particular genius in the construction or handling of the radio, but almost entirely to radio frequency interference. When too much RF energy was reflected back into the radio on key down, the Rockmite's picokeyer would reset chirping out an only slightly irritated 73 in Morse code. Hence, we couldn't use the rig, hence we changed the antenna or repaired the rig, or turned down the bias voltage on the Tuna Topper final until we could use the rig without resetting that little keyer.

Then! Then we did something that was both cool and, (we'd later find out), somewhat daunting. We removed the last of the wires that attached Project TouCans to the Earth and our RFI just went away. Which has been great for signal quality, and as it tuns out it's occasionally been hell on the amplifier.

At present count, we're three transistors down.

After the rig dropped from about 15 feet up to the ground recently, I did a quick inspection and then, (why!!!!??? why did I do that???), decided I'd measure the rig's output power since I hadn't done that in a while. The power meter reported 3 Watts. The rig nominally outputs 5 Watts. I adjusted the bias voltage on the Tuna Topper and.. still 3 Watts. I increased the voltage two more times, and? The final transistor blew out. (Eventually taking the rechargeable battery with it.) KO6BTY and I completed our debug yesterday, reattached the power meter, (which apparently no longer works since it reported 0 Watts at all bias voltages), and fairly quickly blew out the amp transistor again as I blithely upped the bias voltage.

Turns out I can't do that anymore. our keyer RFI safeguard is gone.

Interestingly, we did discover that when the bias is set to low on the amp, there's a whistling feedback tone that appears in the audio output. When the amp is biased correctly, and before it's biased too high and takes out the transistor, (i.e. in nominal operating mode), the whistling tone goes away. Audio debug lives on to a certain extent.

We'll be dropping in transistor number four tomorrow. I'll keep you posted.

 KO6BTY and I attended office hours with Simon Willison yesterday.

Here's what you're seeing. There's an SQL query in our Datasette instance that grabs only the QSOs from our Cibola National Forest POTA back in March. That query resulted in 9 QSOs shown in the table. Our additional CZML (and now Cesium viewer) plugin creates a CZML map that is loaded into a Cesium Ion viewer at the bottom of the page.

I'm not releasing the code that loads up the viewer quite yet because I have to get the access token squirreled away and all that good stuff. Meanwhile the CZML plugin has been released for a few days now.

By the way, we need a way to pull adif files from POTA activations into Datasette. Keep an eye out :)

 I completed the first prototype of my CZML QSO mapping template for Datasette yesterday.

So far, I've implemented animation by using the interval property in CZML. Intervals can be attached to any (?) other tag it seems. I had to intuit what to do on a large degree based on the documentation.

{
    "id": "myObject",
    "someProperty": [
        {
            "interval": "2012-04-30T12:00:00Z/13:00:00Z",
            "number": 5
        },
        {
            "interval": "2012-04-30T13:00:00Z/14:00:00Z",
            "number": 6
        },
    ]
}

I used CZML polylines to display each QSO. Each polyline has a show property. I attached an interval to each QSO of one minute, like so:

.

    "id":"ea1ec",
    "name":"ea1ec",
    "polyline":{
      "positions":{
        "cartographicDegrees":[-106.5569121602622,32.371370471129424,0, -3.689354499999999,42.3504659,0]
      },
      "material":{
        "solidColor":{
          "color":{
            "rgba":[255, 0, 0, 255]
          }
        }
      },
      "show":[
          {
              "interval":"2024-03-14T23:29:00Z/2024-03-14T23:30:00Z",
              "boolean":true
          }
      ],
      
      "width":5,
      "clampToGround":true
    }
  }

The inference that the viewer (happily) made was that if the show property was true in the interval, then it must be false the rest of the time. (The default value of 'show' is true, so I was quite pleased with this implementation instead of the alternative where I might have had to define intervals for when I wanted the line turned off. This solution is far more intuitive to me.

I like several things about how this worked out with Cesium as opposed to other geospatial solutions available on the web. First, Cesium has animation available directly on the web as opposed to a desktop application. 

  {
    "id":"document",
    "name":"my first map",
    "version":"1.0",
    "clock":{
      "interval":"2024-03-14T23:28:00Z/2024-03-15T00:00:00Z",
      "currentTime":"2024-03-14T23:24:00Z",
      "multiplier":60,
      "range":"LOOP_STOP",
      "step":"SYSTEM_CLOCK_MULTIPLIER"
    }
  },
  {
    "id":"k6mdg",
    "name":"k6mdg",
    "polyline":{

The "clock" "interval" specifies the entire time available to the player. I need to modify my template a bit to make the beginning of the interval, (which is the time of the QSO at the moment), match the currentTime, (which is a few minutes earlier to provide a runway into the animation.) I suspect this may be what's causing me to have to click the play button twice to start the animation.

The final nice feature I'll point out today is that the Cesium Sandcastle makes it easy to play and experiment with both CZML and using JavaScript to control the viewer. You can even import CZML into Sandcastle sessions using the viewer's load method and statically hosted files. I used github as an easy platform to serve files from. (Keep in mind that new commits to files take about a minute to reach the raw page.)

On the downside, the documentation for CZML took me a while to get used to and required several mental leaps and experiments, some of which were incorrect. 

Oh! And it turns out you can share and embed slide shows. I'm not an expert at these yet, but they seem promising.