Maximum Usable Frequency > 21 Mhz

     I am currently receiving a station in the Chinese language on 21550.00 Khz varying in strength between -76 dBm and -88 dBm (s7-s9) while my propagation widget is telling me 160 meters is fair and everything above that non-existent. 

     There are some deep fades and very bad selective fading that occasionally renders the signal unintelligible even when the signal is strong. There are some quite strong signals above 17 Mhz.  Given that it’s almost midnight local time this is somewhat unusual, especially given the relatively weak solar cycle.

     There is another station receivable on 21690.00 Khz but it is -90 dBm or less in strength and although I can tell there is a male voice, I can only hear it during peaks and there is too much noise to even discern the language.

     I scanned higher and found nothing and in ten minutes time 21690.00 Khz is no longer receivable, not even detectable.  The station on 21550.00 Khz is also gone.  Nothing above 19Mhz is receivable now.  There is a very strange periodically recurring signal between 18990 Khz and 19001 Khz that is almost like they’re trying to create an image in a spectrograph.  Check it out.  Tell me that isn’t weird.  It repeats about every 30 seconds or so.

19mhz

     This is one mysterious weird signal.  Now 17,985 is the lowest frequency I can receive any voice transmissions on.  The propagation has changed dramatically in half an hour.  Time for me to call it a night.

Art Bell – Retaking the Night

     Art Bell opened his show with Midnight In The Desert, “Taking Back the Night”.  It badly needs to be taken back!

     One of the really cool things about this show is that not only can you listen to it via streaming media but that includes an AAC stream.  AAC is a lossless compression, the audio is absolutely perfect.  There were some odd clicks on the first night but that was resolved by the next show.

     It is SO refreshing to see something done in radio by someone that actually cares about audio quality as well as content.

     Tonight they have Linda Moulton Howe, one of the very few remaining investigative researchers and reporters.  She is always an interesting guest, especially when you have a host that asks intelligent questions.

Anybody Remember the Loran Navigation System?

     On a “marine band” radio, these were radios that used to cover roughly from 1.6 Mhz to 3.6 Mhz, you could receive a sound around 1.8 Mhz that was the sound of the arrival of radio pulses from various Loran Navigation system transmitters.  It was a fairly broadband signal with a distinctive sound that selective fading would do weird things to.

      They discontinued those transmitters in 2010, they’ve been obsoleted by GPS systems.  However, this year eLoran is being brought online as a replacement.  Satellite GPS is accurate but it can be spoofed, jammed, and it doesn’t penetrate some areas such as canyons or inside some buildings.

      I have not been able to find much information on eLoran, can anybody tell me what frequency it will operate on?

      Also, if anybody has an audio recording of the old Loran signal as it sounded on an AM receiver, I would much appreciate it, especially if captured during a period of significant selective fade.