I do a lot of SOTA activating using 2m FM and have developed a few operating habits that can really make a difference. These may seem obvious but might be overlooked by operators new to the game. To get an overview of using VHF for SOTA, look at this article: How to Do A VHF SOTA Activation.
Here are three operating tips when using 2m FM for SOTA:
1. Upgrade Your Antenna
A handheld radio is commonly used for SOTA operation because it is a self-contained, compact radio. These radios always come with a rubber duck (electrically-short monopole) antenna. These antennas vary in quality but they are universally poor performers compared to a half-wave radiator. I’ve measured the effectiveness of many rubber duck antennas on 2 meters and they are somewhere between 8 and 12 dB worse than a half-wave radiator. So an easy upgrade is to use a half-wave telescoping antenna. Another popular option with a half-wave radiator is the roll-up J-pole (often called a “Slim Jim” antenna). An even better choice is a small 3-element Yagi such as the 146-3 from Arrow antenna, which is about 6 dB better than a halfwave antenna. Keep in mind that the Yagi should be held vertically-oriented for FM operating.
2. Open Your Squelch
The squelch circuit in an FM receiver requires the signal to be large enough to flip the squelch open. When operating at weak signal levels, the squelch may mask a signal that is actually readable. A recommended technique is to just open up the squelch control and let the FM noise come through. This maximizes the opportunity to pick out that weak signal out of the noise.
3. Point Your Antenna Everywhere
If you have a directional antenna, make sure you methodically point it in a variety of directions when calling CQ. For example, with a 3-element Yagi, you should divide up the 360 degrees around you into 45-degree sections. Point north, make a call, point northeast, make a call, point east, make a call, and so forth. Also be aware that the direct path to another station may not be the strongest path. This is especially true if you have tall summits around you that can block or reflect your signal. Many times I’ve pointed in the “right direction” to work another station but then found that the signals were strongest with the antenna pointed away from the direct path. So the secret is go ahead and try different antenna orientations to maximize the signal strength, even when you know the physical direction to the other station. Sometimes the radio waves decide to take another path.
Those are my three tips for today.
Do you have any to add?
73 Bob K0NR
If you can’t take a small portable 25 watt mobile radio and battery with you, at least take a 10 watt RFG or Wouxun handheld radio to avoid being a squelch biscuit on simplex using a low power 5 watt handheld.
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Bob, thanks for the 2 operating tips. I plan to op 2 meters using an
Arrow 3 element beam. I did not realize the need to aim it vertically.