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Did Project TouCans Have a Vertical Quarter Wave Antenna for Just a Bit?

 I spent some time testing out a theory about briefly running a quarter wave vertical antenna from the backyard.The short answer? The theory did not pan out during an empirical trial this morning.

A few days ago, while adjusting the antenna with the radio in beacon mode, I accidentally dropped the end that stretched down to the backyard. The sturdy little radio bounced off of some chicken wire below our back deck. The rig—still embedded in the antenna—was about five feet off the ground, hanging from it's antenna mount on the second floor of the house, and still transmitting. When I got everything sorted back out about half an hour later, I noticed something that seemed weird. The radio had reached W3UA and W3RGA just before it went away during my fixes. I knew I had data on the whole thing, so I put off checking things out until last night.

After I updated my database, I wrote a query that found the dropped antenna data

select rowid, id, tx_lng, tx_lat, rx_lng, rx_lat, timestamp, strftime('%H:%M:%S',timestamp) as tod, dB, frequency, Spotter from rm_rnb_history_pres where "timestamp" > :p0 and tod > strftime('%H:%M:%S','13:01:01') and tod < strftime('%H:%M:%S','16:01:01') order by timestamp 

Quickly enough, I found the two stations:



112861661375211-122.4229937.72286-112.041733.31252023-10-05T14:07:0014:07:001614058.0K7MJG
112871661375206-122.4229937.72286-94.958339.14582023-10-05T14:07:0014:07:00914058.0K3PA-1
112881661374995-122.4229937.72286-122.291737.89582023-10-05T14:07:0014:07:00214058.0NU6XB
112851661375503-122.4229937.72286-76.708340.89582023-10-05T14:08:0014:08:00314058.0W3RGA
112841661376390-122.4229937.72286-71.458342.89582023-10-05T14:10:0014:10:00814058.0W3UA
113061661392150-122.4229937.72286-114.458351.81252023-10-05T14:50:0014:50:001014057.5VE6WZ
113071661392145-122.4229937.72286-122.541749.18752023-10-05T14:50:0014:50:00614057.5VE7CC


Notice that everything is going smoothly until 14:08 GMT; then TouCans was spotted by two stations on the East Coast; then it wasn't seen again for forty minutes while I put the antenna back up.

But was this different than any other morning in this time window? Let's find out by narrowing down the stations and expanding the time window.

The first pictures we have of operating the Rockmite with the Tuna Topper amp are from 9/12. So, we'll only look for those stations after that:

select rowid, id, tx_lng, tx_lat, rx_lng as longitude, rx_lat as latitude, timestamp, strftime('%H:%M:%S',timestamp) as tod, dB, frequency, Spotter from rm_rnb_history_pres where "timestamp" > :p0 and tod > strftime('%H:%M:%S','13:01:01') and tod < strftime('%H:%M:%S','16:01:01') and (Spotter = "W3RGA" or Spotter = "W3UA") order by timestamp 



I turned on mapping for the query to show that the stations are on the East side of the US.

84211653280026-122.4229937.72286-71.458342.89582023-09-17T14:06:0014:06:00714057.4W3UA
110311660548883-122.4229937.72286-76.708340.89582023-10-03T13:09:0013:09:00314058.1W3RGA
110501660558911-122.4229937.72286-76.708340.89582023-10-03T13:44:0013:44:00414058.1W3RGA
112851661375503-122.4229937.72286-76.708340.89582023-10-05T14:08:0014:08:00314058.0W3RGA
112841661376390-122.4229937.72286-71.458342.89582023-10-05T14:10:0014:10:00814058.0W3UA
The above data shows that we did in fact hit both stations the morning of the 17th, but...
The morning of the 17th, we weren't in San Francisco, the kid and I were in New Mexico where we did a POTA:


Which leaves the question of what—if anything—was going on on the morning of the third. It looks like nothing all that different, but also, TouCans didn't hit W3UA that morning. Expanding the date range and looking only for W3UA using

select rowid, id, tx_lng, tx_lat, rx_lng as longitude, rx_lat as latitude, timestamp, strftime('%H:%M:%S',timestamp) as tod, dB, frequency, Spotter from rm_rnb_history_pres where tod > strftime('%H:%M:%S','13:01:01') and tod < strftime('%H:%M:%S','16:01:01') and Spotter = "W3UA" order by timestamp 

Reveals we've only ever hit that station twice in the morning since the Tuna Topper has bee in use. Only once from San Francisco—on the morning I dropped the antenna.

What if we ignore the time of day?
40981573487640-122.42100640845337.80776743-71.458342.89582023-04-12T02:20:0002:20:00314058.3W3UA
41091573489297-122.42100640845337.80776743-71.458342.89582023-04-12T02:31:0002:31:00414058.3W3UA
41221573490793-122.42100640845337.80776743-71.458342.89582023-04-12T02:44:0002:44:00314058.3W3UA
44801578665448-122.42100640845337.80776743-71.458342.89582023-04-20T05:44:0005:44:00214058.4W3UA
47741580768206-122.42100640845337.80776743-71.458342.89582023-04-25T03:39:0003:39:00814058.4W3UA
48441581046555-122.42100640845337.80776743-71.458342.89582023-04-26T06:16:0006:16:00414058.4W3UA
48751581049916-122.42100640845337.80776743-71.458342.89582023-04-26T06:40:0006:40:00414058.4W3UA
48661581051306-122.42100640845337.80776743-71.458342.89582023-04-26T06:49:0006:49:00414058.4W3UA
48921581052877-122.42100640845337.80776743-71.458342.89582023-04-26T07:00:0007:00:00414058.4W3UA
48841581054493-122.42100640845337.80776743-71.458342.89582023-04-26T07:13:0007:13:00614058.4W3UA
49041581056299-122.42100640845337.80776743-71.458342.89582023-04-26T07:25:0007:25:00614058.4W3UA
62161635201350-122.4229937.72286-71.458342.89582023-08-10T03:26:0003:26:00314058.1W3UA
66861639707187-122.4229937.72286-71.458342.89582023-08-17T10:18:0010:18:00314058.0W3UA
84211653280026-122.4229937.72286-71.458342.89582023-09-17T14:06:0014:06:00714057.4W3UA
85801653816220-122.4229937.72286-71.458342.89582023-09-20T01:11:0001:11:00514057.4W3UA
86671654143172-122.4229937.72286-71.458342.89582023-09-21T01:54:0001:54:00314057.4W3UA
91861656003250-122.4229937.72286-71.458342.89582023-09-24T03:01:0003:01:00514058.0W3UA
91691656014479-122.4229937.72286-71.458342.89582023-09-24T03:16:0003:16:00514057.4W3UA
103461659301184-122.4229937.72286-71.458342.89582023-10-01T00:48:0000:48:00514058.1W3UA
112841661376390-122.4229937.72286-71.458342.89582023-10-05T14:10:0014:10:00814058.0W3UA
115201661557675-122.4229937.72286-71.458342.89582023-10-06T01:07:0001:07:00514058.0W3UA
114991661558730-122.4229937.72286-71.458342.89582023-10-06T01:16:0001:16:00514057.9W3UA
114861661559149-122.4229937.72286-71.458342.89582023-10-06T01:20:0001:20:00414057.3W3UA

Turns out the solo Rockmite has hit the station a few times, but never in the morning, only at night, and usually from out of town. The only other time W3UA spotted the Rockmite at that time of morning the gang and I were camping at Mt. Tamalpais.



Given the data, it was worth a try to lower the antenna again. I did that exact thing earlier this morning, and the results were exactly as you might have expected. Propagation got worse to everywhere. TouCans only reached W6YX and W6BB and wasn't happy about it. (Rockmites have a pretty wonderful—albeit unintended—audio SWR meter. The sidetone makes audible rasping and sucking noises when the SWR gets out of hand. If things get too far out of hand, the keyer chip will simply reset itself. (This is my safety net for moving the antenna around while the radio is sending.)
So, no new antenna setups, but it was fun to be able to easily play around with the data and try experiments.















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