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 2278 102 1032
AL 0 12082 159 608
AP 0 8 125 5
AR 0 7829 75 695
AS 0 0 3 15
AZ 0 20884 91 1930
CA 0 94159 409 8592
CO 0 18871 122 1410
CT 0 7352 38 315
DC 0 532 0 27
DE 0 1839 3 71
FL 0 44030 133 1790
GA 0 18884 143 942
GU 0 4 125 102
HI 0 2866 64 842
IA 0 6538 28 296
ID 0 9623 181 1143
IL 0 19618 298 731
IN 0 15657 232 548
KS 0 7241 41 373
KY 0 9711 100 504
LA 0 5987 107 357
MA 0 13348 20 802
MD 0 11182 46 401
ME 0 4240 8 542
MI 0 21182 394 750
MN 0 11588 65 438
MO 0 14439 861 762
MP 0 1 48 155
MS 0 4723 321 332
MT 0 3713 24 778
NC 0 22439 101 1379
ND 0 1452 51 122
NE 0 3757 17 184
NH 0 5440 23 530
NJ 0 13258 60 526
NM 0 5810 80 865
NV 0 8026 63 744
NY 0 26403 103 1601
OH 0 28094 111 814
OK 0 8646 1116 808
OR 0 19200 77 2207
PA 0 24649 133 900
PR 0 1620 2505 1309
RI 0 1945 2 86
SC 0 10202 125 476
SD 0 2048 36 141
TN 0 19895 55 939
TX 0 53178 368 3501
UT 0 17769 198 939
VA 0 20581 83 1166
VI 0 11 108 148
VT 0 1964 11 282
WA 0 31628 116 3477
WI 0 11492 66 397
WV 0 5573 133 713
WY 0 1929 14 424
Totals 0 737418 10121 51966