AMband.org » Radio History

KNSN nee KSON gets new tower after 2004 Collapse

Ted — Tue, 13 Jan 2009 14:54:35 +0000

From CGC Communicator – The new KSON(AM) tower was
completed and activated today at about 4:30 p.m. according
to Joel Saxberg who performed the RF matching. The tower is
grounded at its base and skirted to permit RF to be induced
onto the structure.

Actually, two stations are diplexed onto the tower, each
with its own set of tuning skirts. The stations are KSON(AM)
on 1240 kHz, now KNSN with its recent call sign change (“K North
South North” as we call it); and KURS on 1040 kHz. The remaining
portion of the old tower structure will soon be dismantled and
the RF matching to the new tower will be checked after that
(there is obviously some mutual coupling between the towers).
Both stations are currently operating at full power.

Congratulations to all parties involved and particularly
to Eric Schecter, KSON’s former Director of Engineering, who
performed a large part of the planning, and to Bill Eisenhamer
who was involved in this project from the beginning and still
has a large number of finish-up details to tidy up.

Following is a December 10, 2008 photo showing the remains
of the old tower (left) and the new tower structure. The new
tower was just about completed at the time of the photo but
still had a gin pole on top:

http://earthsignals.com/add_CGC/Images/KSON/kson_DAWN_sm.jpg

Here are some photos shortly after the collapse.

Radio-Locator Decoded

Ted — Thu, 19 Jun 2008 14:47:51 +0000

I have received a lot of questions about the contours shown on the Radio-Locator maps. For AM they are:

Red – 3.0 mV/m – Generally the Sellable area of the station
Purple – 0.5 mV/m – Rural protected service area, but nobody would buy ads.
Blue – 0.1 mV/m – You might still get it on a car radio

For FM they are:

Red – 60 db/uV or 1.0 mV/m – Protected service area for Class A and C stations
Purple – 50 db/uv or 0.316 mV/m – A pretty weak Signal, nobody would buy ads.
Blue – 40 db/uv or 0.1 mV/m – You won’t pick it up, except in rural areas

I determined this by comparing the plots of sample stations in Radiosoft’s Comstudy with their Radio-Locator maps. Hopefully this clears a few things up!

Canadian AM Stations Wink Out

Ted — Tue, 27 Feb 2007 18:13:56 +0000

All across Canada broadcasters have been moving their AM signals over to the FM band. The Canadian Radio Television C ommission will authorize only so many stations in each market – to assure that each station has the economic potential for success, and each station has to promise to meet a specific programming need. In many Canadian markets there are several FM channels available.

Most of Canada’s population is clustered on the border with the US. The FM channels are generally not limited to the north by other stations, so it has been possible to move many AM stations over to FM channels. The CRTC requires that the AM signal go off the air when the FM takes over.This may be good news for AM stations, because the night interference that these now silent Canadian AM stations cause to US stations is only on paper. Many Canadian AM stations have high night power and complex directional antennas. They did not always work as planned due to breakdowns, icing and other problems, so they sometimes caused a lot of interference to US stations at night.

The Canadian government generally has not deleted the frequency allocations for these stations for international purposes, but keeps them on the books to reserve the channel. In fact, several large facilities were taken over by another station in the same market that now has a better signal. Some others were moved to another town.

There are probably a number of US AM stations that could improve their signals because the Canadian stations that were protected in the original design are no longer there. While the Canadian government protects the allocations, it is not unheard of for the FCC to issue an STA for increased night (or daytime) power when the foreign station clearly has not been operating for a number of years.