Now I have a little more power to play with, it is interesting to see what VHF radio on 2m is capable of.  On Friday 23rd January 2004, I had a very enjoyable QSO with Dave (M0WAR) whose QTH is in Borough Green, near Sevenoaks.

I was using my FT-847 @ 50w and Dave (M0WAR) was using a Kenwood 2000 @ 40w.  Both of us were using tri-band collinear Antennas.  The QSO was made on 145.450Mhz FM (F3E).

I decided to try and model our QSO using "Radio Mobile" Software (Ver 5.0.0).  This is the terrain map of our locations.  With a bit of imagination you can fill in the gaps and see the Thames estuary, the North and South Downs, and the outline of the Kent Coast.

We recorded signal reports of 54 for M0WAR and 56 for M0PDJ, both with significant flutter, however the signals were never unreadable.  Here are the figures from "Radio Mobile" which roughly confirm our experience.  

The following plot shows the radio path (from left to right) from M0PDJ to M0WAR.  The propagation mode is diffraction which indicates that the signals do need to bend over the top of the peak of terrain to complete the path to Borough Green.  The green part of the plot are locations with readable signals, and the red parts are locations where the signal is estimated to be unreadable.

The following plot shows the reverse path (also from left to right) from M0WAR to M0PDJ.  

A fascinating piece of software, which I will need to play with more.  Radio Waves DO NOT travel in straight lines!!

Ham Radio Menu

My Shack

• Icom IC-756proII
• Yaesu FT-847
• Carolina Window 80
• 20m Dipole
• Triband Co-Linear
• 6m Halo Loop
• 4m Halo Loop
• 2m 4ele Quad
• 70cm 7ele ZLspecial

My Vehicle

• Yaesu FT-100D
• Ascom SE550
• Yaesu ATAS 120
• Triband Whip
• 4m whip

My Field Portable Kit

• Clark Mast
• HF beam (20m/15m/10m)
• Log Periodic (50-1300Mhz)

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