Amateur radio license map info

Welcome to my little spare time project. I've been working on this on and off for about a year as time and motivation allows.

This is more of an excuse to have some fun with Maps and Geocoding than anything else but it hopefully provides something interesting to play with. "Geocoding" means to convert physical addresses into longitude and latitude coordinates. Behind the scenes, this site has been slowly geocoding all active amateur radio addresses in the FCC license data. The FCC data includes all licenses which have a status of "active".

I've found it an interesting project with lots of little challenges. Some of this is because of the wide variation of population and therefore "ham density" throughout the country. I've had to balance that with performance issues both at the database query level and practical limitations of Google Maps. The data is also kind of messy with multiple licensees at one address and multiple addresses at the same location. This last issue is mostly due to spelling variations. In general, one marker appears on the map for each unique latitude / longitude point.

The performance / data quantity compromise I've come up with is that it searches within a 20 mile radius of the map center and has a limit of 200 location markers. The results are sorted by distance which means that the circle is complete until it hits the 200 markers. I haven't found a gridsquare that has more than 200 so if you center on a gridsquare, I think we always get all in that square.

The initial geocoding was done in bulk using Nominatim / OpenStreetMap. This succeeded in finding about half of all addresses. Then over a long period of time the rest were processed using Geocodio.

Geocoding continues using Geocodio at a rate of 125 per hour or a total of 2500 per day which keeps it within the free limit.  Every hour it selects 125 addresses from the database to geocode. These are chosen with the following priority.

  1. New addresses that have not be geocoded before.
  2. Those that previously succeeded on OpenStreetMap. Reprocessing these with Geocodio seems to be improving the results.
  3. Those that previously failed. Some now succeed because of better data.

A weekly import from the FCC usually happens early Wednesday morning eastern time. Only those stations with a status of "active" are retained. About 1000 addresses are added and deleted each week. Geocoding the new addresses is usually completed by late Wednesday.

Of course some addresses are PO Boxes and other mailing services. Addresses starting with "PO Box" are simply excluded. Also, many licensees are not active in the hobby. Be that as it may, it can be fun to play with the Street View feature of the maps to look for antennas.

Although I've only considered data from the USA, it's written in a generalized way so it can handle data from other countries but I'm not aware of any other countries who make their data publicly available.

It's built with Drupal 8. The code is all on Github here, here and here.

Anyway… I think it's pretty much "done" in terms of new features unless someone comes up with a good idea. I've probably spent way too much spare time on this already and it's time to get my antenna up again and do some QRP construction. Feedback is welcome. The easiest way is by email to tetranz (at) gmail.com

73
Ross  KT1F

Geocode report

StateNewSuccessfulNot FoundPO Box
AK 0 2269 87 1098
AL 0 11858 162 629
AP 0 7 126 6
AR 0 7675 89 694
AS 0 0 4 15
AZ 0 20412 168 1940
CA 0 96275 521 9134
CO 0 18462 126 1425
CT 0 7367 46 319
DC 0 515 1 24
DE 0 1792 5 72
FL 0 43308 178 1836
GA 0 18594 185 966
GU 0 3 138 121
HI 0 2896 75 896
IA 0 6486 33 284
ID 0 8946 340 1107
IL 0 19687 275 755
IN 0 15492 226 554
KS 0 7176 42 379
KY 0 9149 387 529
LA 0 5942 87 376
MA 0 13347 15 807
MD 0 11191 45 429
ME 0 4209 17 550
MI 0 21094 345 724
MN 0 11551 46 422
MO 0 14370 798 777
MP 0 0 56 176
MS 0 4776 310 354
MT 0 3557 25 771
NC 0 21669 129 1397
ND 0 1474 40 130
NE 0 3691 19 187
NH 0 5318 44 523
NJ 0 13306 107 539
NM 0 5861 84 902
NV 0 7864 59 802
NY 0 26578 103 1649
OH 0 27982 140 821
OK 0 8538 1029 839
OR 0 18865 126 2238
PA 0 24296 162 882
PR 0 1496 2357 1302
RI 0 1952 1 93
SC 0 9887 142 476
SD 0 1951 29 143
TN 0 18873 307 919
TX 0 52272 445 3574
UT 0 17457 186 936
VA 0 20230 82 1168
VI 0 13 108 145
VT 0 1911 12 283
WA 0 31271 221 3555
WI 0 11302 92 391
WV 0 5436 192 739
WY 0 1806 20 404
Totals 0 729705 11194 53206