Hearing a station identification or unique slogan over the air is the only good way to confirm a station reception. Some stations might verify reception reports, but this is time-consuming, and it is better to be certain of your results before submitting them for confirmation.
In one recent case, i was pretty sure I identified a particular broadcaster after looking up possible stations for the frequency. Then the frequency that was announced was not the frequency shown on the tuner readout. This was an image signal due to the single-conversion design of the BCL-2000.
While tuning in mediumwave stations and trying to obtain station identification, I found several tools and methods to be quite valuable for determining the probable id:
* Check affiliate station lists for nationally-syndicated radio shows. Programs such as Coast to Coast AM are broadcast on a number of frequencies across the country. Thankfully, the Coast to Coast AM website lists all of their affiliate stations. So when I hear this show on a frequency, I check the affiliate station list and try to match the frequency to its sender.
* The FCC AM Radio Database Query page allows lookups with parameters such as city, state, callsign, and frequency.
* The Find Radio Stations site performs searches based on city, zipcode, callsign, and frequency. This site's pages often turn up in Google search results for broadcast frequencies.
Some stations that are hard for me to identify are broadcasting in languages other than english. Sometimes they will broadcast an english station identification on the hour, or sometimes they will announce their station's nickname (e.g. Oakland's Best Japanese Radio) in English.
When receiving a signal that I can't identify, I track these reference points in my log:
* approximate time of day (AM stations in the United States sometimes have different licensing conditions for transmission power during the daytime and during the nighttime)
* type of content
* the approximate direction the radio is facing (weak and distant AM signals tend to be directional in relation to the internal ferrite bar)
By the way, I would like your advice on tracking down stations believed to be in Mexico. Is there a good way to look up the callsign, website address, transmission strength, etc?