Boat anchors, somehow you forgot the classic 100KHz crystal calibrator.
I can not speak for anyone else but personally I did not forget something like the 100 kHz crystal calibrator built into some older radios. And even if not built in you can build one for a few dollars and add them to just about any radio. And I think that might have been what ridgescan might have been referencing as calibration points on his radio.
But, I do not like to use them when other options are at hand.
Such crystal calibrators are pretty good when dealing with mainstream broadcasters. Most of these broadcast stations are on some multiple of 5 kHz and you can often “eye-ball” the dial to get within 5 or 10 kHz between known 100 kHz CC markers. But typically using such a marker with the average boatanchor dial you probably can not get closer than maybe 5 kHz, and sometimes not even that close.
So what happens when you are trying to ID a station that is not on a 5 kHz step? Say Radio Gazeta, out of Sau Paulo, Brazil, in Portuguese and on 9685.3 kHz. CRI out of China also transmits in Portuguese on 9685.0 kHz. Yeah, you try to catch the IDs and hope you can make it out, but when dealing with a foreign language knowing the real frequency can be a real help to narrow down what you expect to hear in the ID. Or when you hear a foreign language that you can not ID, knowing the real freq can help narrow the possibilities down quite a bit. If you can just tell the freq is about 9675 or 9680 kHz and the language is one you can not ID, might that be Turkish, Tibetan, Hindi, Arabic, Mandarin, Chinese, German, Sudanese, or Spanish? Because all are on those 2 freqs, several are scheduled at the same time from different stations around the World. But knowing that the station you are hearing is actually on 9677.8 kHz can quickly narrow it down to probably Voice of Justice, in Azeri, out of Azerbaijan, a language I probably would not be able to correctly ID by ear.
And in the case of the OPs post, he thought the station was near 15100 kHz, but it actually turned out to be 15540 kHz. Using a 100 kHz CC without referencing an external source such as WWV/WWVH/CHU would result in him thinking it was 15140 kHz, still incorrect and not a help in trying to ID the station.
Yes, crystal calibrators were a good thing back in the day, but after I got hold of my first BC-221 in the 60’s I pretty much never used a CC again, and my logs contained much fewer “guesses” and much more accurately recorded frequencies. And once you learn how to use the –221 or LM-XX series they are pretty much as quick and easy, while being much more accurate, as finding the nearest 100 kHz marker tone and guessing the possible freq from interpolation.
T!