1900 US Counties Confirmed on QRZ.com

A BIG thank you to Richard, N7WFK, located in Canadian County, Oklahoma, for being my 1900th United States County contact confirmed on LoTW and QRZ.com (1900 out of 3,007).

I noticed that it took me much longer to complete the last 100 Counties than it did to go from 1700 to 1800 Counties.  My q-rate for making contacts with new US Counties has noticeably decreased.  All the same, I am undeterred as completing contacts with all 3,007 US Counties is a long-term goal.  One thing that I have learned in life is to enjoy the journey more than the arriving at the destination.

Chasing US Counties is great fun and if you are looking for a new challenge in amateur radio, I encourage you to dive in.  You may be surprised how far you have progressed already.

Good DX and 73, NJ2X

Usefulness of Harmonics in Radio Direction Finding

Harmonics are undesired transmissions produced at multiples of the intended transmission frequency. 

Most radio frequency transmitters produce harmonics at relatively low power levels, as compared to the fundamental frequency (also called the first harmonic).  The second harmonic appears at double the frequency of the fundamental.  The third harmonic is at triple the frequency of the fundamental.  For example, if the fundamental transmit frequency is 146.550 MHz then the second harmonic would be at 146.550 * 2 = 293.1 MHz and the third harmonic would be at 146.550 * 3 = 439.65 MHz.  Harmonics are a potential source of radio frequency interference.

In general, in amateur radio transmitter harmonics are undesirable.  However, there is one situation where an amateur radio operating can benefit from harmonics - radio fox hunting.  

A wide-band receiver is useful for radio fox hunting

In a radio fox hunting, the objective is to locate a hidden transmitter.  Hunting with a wide-band receiver allows the radio fox hunter to tune to the hidden transmitted signal's 2nd and 3rd harmonic frequencies as a way of effectively reducing the received signal strength.  This can provide a competitive advantage since a weak received signal at a harmonic is much easier to locate directionally than a strong signal at the fundamental.

This technique works best when you are in close proximity to the fox transmitter.

Good DX and 73, NJ2X