dwtpa97 said:
Since energy cost is such a big factor, why doesn't KNOM use a higher tower (which would allow them to lower their wattage)? I know from other posts that they can't go any higher at the airport, but surely there are other sites available. If they could cut their wattage in half, wouldn't that result in some savings?
Going back to the beginning:
Land availability. At the time (1970-71) Nome was landlocked by The Bureau of Land Management. It took a lot of congressional delegation involvement to get ANY land.
Power availability. If you check a Google Map, follow the coastal road to the East of Nome. The KNOM transmitter is just before the Nome River Bridge on the right side of the road. Very nice ground conductivity, being up against Nome River right at Norton Sound (salt water). City power extended only about a mile more to the East to the FAA Vortac/outer marker site. The folded unipole design produces very nice groundwave coverage at the expense of sky wave but that's exactly what's needed for the area.
Alternate sites? To the North, mountains (very close). To the East the road moves somewhat inland and is a little higher and more dry. Plus, no power available. To the west no road, no power. Power was installed a little to the Northwest in the last few years but, again, dry higher ground that is even closer to the airport than the present site.
Airport. There are two airports at Nome, both of them on the opposite side of the city from the KNOM (also KICY) transmitter site. The KNOM site is slightly East and South of The KICY site. They're both very close to the flight path to the primary airport's instrument runway. In fact twice KICY lost a tower to aircraft impact.
KNOM dealt with the tower height limitation by using a folded unipole antenna which was a continuing problem until the original 3-fold design was changed to 6-fold a few years ago. Once some initial problems with the modification were fixed it's been much more user friendly.
For about 20 years 10 kW day/5 kW night covered the desired area but as villages got "city" power, added electrical appliances and started buying motor vehicles the noise floor rose and, to be heard, the power was upped to 25 kW days; 14 kW nights just to stay even. The noise floor is still rising (we're talking 200+ mile listening area) and it would be nice to up to 50 kW days. With a new, more efficient transmitter and DCC it might be affordable but it would be a daytime improvement only and consider the length of days up here. Super long in summer and measured in minutes in Winter. So higher nighttime power would solve that, right? Yeah. If The FCC would allow it. But they won't because of a crescent shaped interference zone with a station in Seward. That station is willing to waive because the zone is on an uninhabited glacier. Apparently somebody in D.C. thinks global warming might someday turn that ice into prime subdivision territory and won't budge on anything more than the current 14 kW night power.
Oh yeah, I left out the wind loading of a higher tower. The present 230-foot tower is of 1.75 inch solid rod stock with four levels of guys. Ice often builds to another 3 inches (plus) and that's when the wind kicks up to 70 MPH on a nice day. Taller would....well, you can imagine.
Good questions, though, and nice to sort through memories to address them. Thank You!