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The Reverse Beacon (RB) Network

So what is a RB? The easiest way to explain this is to say what a 'Forward Beacon' or, more

commonly labeled, a Beacon station is.

A beacon station transmits signals on a regular basis with the intent that many stations be

able to receive it to determine band condition. A beacon station does not listen for replies,

would like to occupy an exclusive segment of band space and, other than its intended

purpose, is not useful beyond its one purpose.

A reverse beacon is exactly the opposite. An RB only listens to band activity and reports its

receptions to a commonly accessible point (in this case via the internet). Every station simply

having a QSO or calling CQ provides signals for the RB to receive and, as such, an RB

occupies no band space while it listens and never transmits unless the operator does so to

have a QSO.

The RB Network is not a new idea. I became interested in systems like the RB Network

before I had discovered WSJT and JT65a via the PropNet PSK system and, to me, JT65

seemed a much better alternative for such a system. It didn't require active beacon stations

sending specific text (as PropNet does) and worked more reliably at the weakest (most

interesting) signal levels. Basically I saw that you could gather all the information necessary

to determine a transmitter's location simply by watching the band for normal traffic and the

highly structured JT65 messages makes extracting the details trivial.

So, just over three years later, the JT65 RB network has collected (and saved) near 10 million

reports without ever having need to intentionally transmit a signal as a predefined beacon

text. While less specific than data collected by PropNet or WSPRNet (in that with the former

an indication of power and/or antenna gain is given) the JT65 RB Network, again, does not

require stations to transmit specialized messages solely for the sake of beacon action and I

consider this a positive consideration.

I don't know if the data collected will ever be of any use as a database of propagation

conditions, but, it certainly is seen as a useful tool for day to day users of JT65 on the HF

bands and I hope you will consider contributing your reports as well.

You may view reports sent to the JT65 RB Network at;

http://jt65.w6cqz.org/receptions.php

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Carrier 42 HQX Manual de usuario Pagina 29