N2XE Laboratory
The N2XE Beacon Project was started in December, 2004 by Paul Stroud, AA4XX, Raleigh, NC and John Ceccherelli, N2XE, Wappingers Falls, NY with the goal of having a little fun and to go where no diminutive signal has gone before. The beacon transmitted a unique code word each evening. Receiving stations were required to correctly copy the code word in their report. The word was published the following morning.
By the end of the project, a world record was established on 80 meters with Wild Bill Tippett, W4ZV, copying a 26 microwatt signal over a distance of more than 500 miles and he achieved great fame and fortune. A press article describing the monumental event can be found here
The beacon transmitted from an off-center-dipole, inverted L or Fly Rod Vertical. Below is some advice that was posted on www.n2xe.com for new weak-signal aficionados to help them acquire the infinitesimal signal:
Some Information About the N2XE Beacon
The N2XE beacon transmits from a Ten Tec Argonaut V, Elecraft K1 or Small Wonder Labs RockMite. Antennas used are an 80 meter off-center fed dipole, 160 meter inverted L or Fly Rod Vertical (FRV). The dipole favors the NE and SW from Wappingers Falls, NY. The inverted L favors the SW and the FRV radiates equally poorly in all directions.
Message Format
The Message format is "VVV N2XE/B ABCD ABCD ABCD" where ABCD is the code word and it changes every day. The message transmits continuous wave Morse code at 12 words per minute.
Frequency
Frequencies may vary but usually it's 1999.5 KHz, 3545.5 KHz and 7023.5 KHz. Hours of operation are local sunset to sunrise-give or take.
Reporting
Reception reports may be sent to n2xe@verizon.net . Include the code word in the e-mail subject line. Your report should contain the following:
Call sign, name State Time(UTC) Grid Square RST Rig & Antenna
Power Output
Power output is measured and calculated using two methods. The raw output from the beacon transmitter is measured with a MFJ 872 power and SWR meter. This meter has been calibrated to be accurate within +/- 5% in the 0.2 to 1 watt range.
After measuring the transmitter output, the attenuation to obtain the desired power output is calculated. I use precision Hewlett Packard and Tektronix 6dB, 14dB and 20dB attenuators. A Hewlett Packard 8494A step attenuator provides 1dB increments. I can vary the transmitter power supply to make minor adjustments to the raw output. After inserting the calculated attenuation, the power output is verified with an Agilent 8563EC Spectrum Analyzer. If the calculated and measured values don't jive, I have to figure out where I screwed up. It's usually a math error.
When conditions are favorable and there are some great operators listening, I'll play RF limbo to see how low they can go. The minimum received power to date is 27 uW (.000027 watts). If you cannot hear the beacon, I might be playing RF limbo.
Can't Hear it?
Every once in a while, I'll do a calibration run in turbo mode, running ridiculously high power at 10-50mW. If you cannot hear the beacon, there are several things you can do about it:
a) change your location
b) change your antenna
c) change the way you listen
You can't do much about location but several free programs like VOACAP and W6ELprop can tell you if you should be able to receive the N2XE beacon. Google it for the websites.
From the data I've acquired, nothing grabs a weak signal better than Dr. Harold Beverage's antenna-especially on 80 and 160 meters. Dipoles don't fare very well on those bands but are more effective on 40 meters.
The way you listen to the signal is probably more important than the rig. The sidetone pitch used makes a HUGE difference. Bill Tippett, W4ZV, the current 80 meter MPW record holder, uses a 270 Hz tone. Many people are uncomfortable with a note that low (I like it around the note A, 440 Hz) but it is effective and for reasons to complex and lengthy to go into here.
The human ear/brain can distinguish a low note better than a high note. It has been reported that a pedestrian CW op can easily pick out a signal 3dB below the noise. It is estimated that the 27uW signal W4ZV received was 6dB below the noise. The limit of the human ear/brain is about 10dB below the noise. Since the N2XE beacon is never above 100mW, count on it being near or below your local noise floor. Again, a half-way decent Google key-word search will net tons of good information on human ear-brain science.
Beacon Location
The feedpoint for the OCD is located at:
41 36' 15" N
73 52' 30" W
Grid Square FN31bo
This is 65 miles due north of mid-town Manhattan, roughly half-way between Albany and New York City on the Hudson river.