Re: Currently Active Beacons

[robman501a]

How do you decode these beacons so you know what you are listening to? Also how do you know what mode they are in?

[cwguy]

Robman -

There's really not much to decode.  Some of the beacons send a morse code letter or two, while others send a series of "dits" or "dashes" - hence the term "ditter" or "dasher".  The sending speed is slow enough that you can write down the dots and dashes and convert them to their equivalent letter using a morse code chart - unless you already can copy code by ear.  As you see throughout the forum, a lot of guys use a spectral display to look at a slice of bandwidth and the dots and dashes practically write themselves right onto the computer screen!

Most of the beacons can be identified pretty much by just tuning onto their posted frequency. If you hear a beacon, it's probably the one that's posted on this list. 

Is that what you were asking about?  Maybe you know all of this - I'm just not sure what you meant by "decode". 

[robman501a]

Oh, I haven't came across any HF beacons yet but if they have the same sounds as the LW NDB beacons, then how can you tell what you are listening to? That was what I meant by 'decode' but first I have to look for these HF beacons to hear what they sound like.

[Tom S]

Well it helps to know Morse code for one.  That way you'll know what Morse characters, if any, the station is sending.  However, a lot of them just send strings of dits or dashes.  The HF pirate beacons don't have the same sound as LW NDB's.  NDB's are sent in MCW mode, that is an AM carrier with Morse imposed upon it.  These pirate beacons are usually just plain CW. 

[cwguy]

Tom is right - and that means you'll be listening for the HF beacons with a receiver capable of SSB reception (in order to hear the "tone" of the morse code - or cw).  Your receiver should be in the "cw" mode, or lacking that, USB or LSB will work just fine.  A lot of the ham gear I come across seems to receive the same whether in USB or CW mode (the 'same' meaning the freq readout is the same between those two modes, and the signal will sound unaffected when switching between those modes) - the mode switching just changes how the transmitted signal is handled - the receive is the same however.  This may not be for EVERY radio out there...but it seems common.

In short, use CW or USB modes, tune for a beacon on the list, write down the dots and dashes, and I'll bet you can find a written chart of the code online so you can translate what you hear. 

At this point, it's a lot like listening to an NDB!

And, as Tom said, a lot of the beacons just send dashes or an endless string of dits....

[Teotwaki]

How do you decode these beacons so you know what you are listening to? Also how do you know what mode they are in?

Someone should have pointed you to this thread with links to audio recordings of various beacons and who captured the sound.

http://www.hfunderground.com/board/index.php/topic,19965.0.html

There is no guarantee that you may hear any of them but at least this is a good sample of the wonderful variety out there. Try using your radio's CW mode and narrow filters. I have found that it is good to be patient. I may set the radio on a frequency and just leave it for a while as a weak signal might slowly increase in signal strength and become audible. Try different times of day and night. Sometimes the beacon's frequency will drift so tune a little high and low.

Jim

[Teotwaki]

--------snip-------  A lot of the ham gear I come across seems to receive the same whether in USB or CW mode (the 'same' meaning the freq readout is the same between those two modes, and the signal will sound unaffected when switching between those modes) - the mode switching just changes how the transmitted signal is handled - the receive is the same however.  This may not be for EVERY radio out there...but it seems common.-----------snip---------

What those radios are doing is displaying what the center of the carrier frequency would be for any mode BUT they switch in the appropriate filters, tuning offsets and demodulator to properly capture the modulated signal.The discussion could take up a whole thread. Lots of good explanations out there:

http://www.hamuniverse.com/ssbinformation.html

AM signals have the carrier at the center frequency plus both upper and lower sidebands. USB mode is only the upper sideband with no carrier, LSB is the lower sideband only and CW is simply the carrier being keyed on and off at the center frequency.

[cwguy]

Nice graphical representations, Jim.  I don't know what receiver Robman is using - I thought giving a simple answer might get him on his way.  If he's using an older receiver without a digital frequency readout, he might have to hunt a bit with an analog dial.

Robman, any luck yet?  Jim's technique is a good one - just parking your receiver on a known frequency and seeing if a beacon presents itself over time will often yield results!