A Basic Introduction to VHF Contesting with a Colorado Emphasis

Bob Witte, KØNR
25 October 2015

This is a brief introduction into how to operate during a VHF contest. The main contests, roughly in order of popularity, are the ARRL June VHF Contest, the ARRL January VHF Contest, the ARRL September VHF Contest and the CQ Worldwide VHF Contest in July. 

I prefer to think of these “contests’ as “activity weekends” because the word “contest” often makes people think of the fast-paced, chaotic, band-crushing experience of HF contests. VHF contests usually have a much different feel. The problem with the VHF bands is that they are often underutilized. You put out a call on simplex and nobody is there. Dead silence. But on VHF contest weekend, you are sure someone is going to be on the air, so the event tends to increase the activity, bringing people out of the woodwork. A VHF contest is more like a friendly reunion of local VHF enthusiasts.

(Sometimes a VHF contest can get pretty intense, especially if there is a significant band opening on 6 Meters. Then things start to sound like the HF bands with signals coming in from across the country.)

Frequencies

Frequencies above 50 MHz (6m and higher) are used during the contest. Most of the operation will be on 6 meters, 2 meters and less on higher bands. Most of the operation will be on the SSB portion of the band, so if you have an all-mode VHF rig, you’ll want to use it. Perhaps you have one of those HF rigs that also does VHF, such as the ICOM IC-706 or the Yaesu FT-100D. This weekend will be a great time to try it out.

The standard SSB calling frequencies are:
50.125 MHz
144.200 MHz
432.100 MHz

Most SSB operation on VHF is done using horizontal antenna polarization. A yagi or dipole antenna with radiating elements parallel to the ground produces a horizontally-polarized signal. A vertical whip antenna, commonly used for FM, produces a vertically-polarized signal. Working a station with opposite antenna polarity causes a substantial signal loss, so it is best to maintain the same polarity. For serious SSB operators, this means horizontal polarization.  Kent Britain WA5VJB designed a series of homebrew yagi antennas, that are cheap and easy to construct. See Cheap Yagi Antennas

CW (Morse Code) is used on the weak-signal VHF bands, often intermingled with SSB operation. It is fairly common to have a station switch from SSB to CW when signals are very weak, since CW will get through at lower signal levels. You don’t need to be able to work CW to enjoy a VHF contest but it does have advantages.

If you only have FM gear, you will be at a disadvantage but you may still be able to work a bunch of stations. Starting in 2016 the ARRL contests allow the use of the 2m FM calling frequency, 146.52 MHz. Don’t monopolize this frequency. If it gets busy, move off to any of the other standard simplex frequencies. Never use a repeater for contest contacts.

The FM calling frequencies for the other bands are:
52.525 MHz
446.000 MHz

Operating Categories

The VHF contests have quite a few operating categories to choose from, depending on the number of operators at a particular station, the power level and other factors.

Feel free to read the rules to understand what is available, but for beginners these are the most relevant categories for the ARRL contests (CQ VHF is a little different):

  • Single Operator Low Power – this is the “standard” single operator category, without running a big amplifier. Power limits are 200 W PEP on 50/144 MHz; 100 W PEP on 222/432 MHz; 50 W PEP on 902 MHz and higher.
  • Single Operator 3 Band – this is a new category starting in January 2013. Use 6m, 2m & 432 MHz only; 100 W or less on 6m/2m, 50 W or less on 432 MHz
  • Single Operator Portable – this is the QRP category, 10 W PEP or less, portable power source, portable antennas, cannot be set up at a permanent station location
  • Single Operator FM Only – this is a new category starting in January 2013. Use FM only on the bands 6m through 446 MHz, 100 W or less on all bands.

You might also try being a rover, which means operating from more than one grid during the contest. If you operate in a Rover category, you need to say the word “Rover” after your callsign so that other operators know that you will be operating from multiple grids:

  • Rover – this is the “standard” rover category, 1 or 2 operators, use all bands above 50 MHz, 1500 W PEP
  • Limited Rover – operator category, 1 or 2 operators, 6m – 432 MHz only; 200 W PEP or less on 6m/2m, 100 W PEP or less on 222/432 MHz

As a beginner, you can probably just choose your category based on the equipment you have. Or, if you want to go mountaintopping, consider operating as Single Op Portable. If you want to operate mobile from a number of grids, then choose one of the rover categories.

Making A Contact

OK, so you get on the right frequency and the right mode. Now what? You need to make a contact. An official contact requires that the two operators exchange callsigns and grid locators. VHF grids are a system that divides the world up into rectangles that are 1 degree of latitude by 2 degrees of longitude. You can work each station once per band for contest credit (except for rovers, who get to work everyone again in a new grid).

For a map of Colorado with Grid Squares shown, see
http://www.k0nr.com/rwitte/vhf_grids.html

All of Colorado Springs and Pueblo are in grid DM78.
All of greater Denver and Castle Rock are in DM79.
Longmont, Loveland and Fort Collins are in DN70.

If you are close to the edge of a grid, you will need a good map or a GPS receiver to figure out your grid.

More information on VHF operating can be found at the Rocky Mountain VHF Plus web site: www.rmvhf.org

Plug it in, turn it on and work someone on VHF this weekend.

73, Bob K0NR