Activating SOTA on VHF/UHF - Radios, Antennas, and Tips

Wanted to create a series of shorter videos focused on those interested in SOTA and/or newer activators. This is a ~10min summary of tips, radios, filters, antennas, etc for activating on VHF/UHF.

Additional info & links are in video description, and please check out channel playlist with 3 other videos focused on newer activators (1 Resource Overview, 2 Choosing your first Summit, 3 Activator Rules). Additional videos will be added in the future, and hoping they help inspire others to get on a summit for the first time! 73, James WA7JNJ

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I have done a few on an FT3DR. It works depending on where you are, I am trying to get a hold of a mountain topper QRP rig. Thanks for putting the video together.

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I’ve had the FT3DR get overloaded by NOAA stations multiple times as well as desensed by tower farms on summits. The best HT I’ve used for SOTA, without a doubt, is the FT270. 2m superhet. I’ve never experienced any sort of overloading or desense on that radio, even when the FT3DR had issues.

On a summit in W4G, I was receiving NOAA on the FT3DR tuned to 146.52 as clear as though I had tuned it to the proper 162.55 frequency. The FT270 was quiet as a mouse.

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Good stuff James!

I agree the FT3DR struggles on summits with high RF. Bandpass filter mostly fixes that. The APRS spotting capability that I get from the FT3DR has saved a few activations for me, so I accept its limitations. I have an ancient Kenwood TH-215A that I got for free and plan to use on our high RF summits (the Tigers, Squak Mtn, etc) once I rebuild the battery pack.

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Nice video, James, well presented.

In addition to your suggestions about antennas, I recommend experimenting with polarisation. I’ve found that horizontal polarisation outperforms vertical from summits and even tilting the average HT over so its antenna is horizontal can improve signal levels remarkably. This has to be done at both ends of course. Use your Arrow yagi or other antennas in horizontal polarisation and you’ll be pleasantly surprised at the improvement. I know, I know, FM is vertical, but why? It’s just convention arising from the convenience of vertical antennas on cars and on top of HTs. Just try it.

Then there’s SSB and (dare I say) CW, if you want to really find out what VHF and UHF bands can do. It’s another world.

73 Andrew VK1DA/VK2DA

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“Rule #1: Don’t use a Baofeng”.

Love it.

The FT5DR seems to burn through battery also, especially w/ APRS.

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Thank you for the feedback on FT3D experience, and interesting to hear it’s not just me. (-: I did seem to notice more interference (than FT70) and finally purchased the 2m band filter. Like Josh mentioned, I also like the APRS/GPS for spotting, texting spouse, etc with FT3D… always pros/cons. Very cool to hear about the FT270, and always interesting when you can compare like that! 73, and thanks for sharing! James WA7JNJ

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The FT70 is well known for having better RF strong signal handling than the FT3 and FT5.

Worth checking is VHF/UHF Handheld Performance Comparison (all QST tests)

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LOL… Many of us have learned rule 1, and was good for me to learn early. The Boafeng does surprise me at times with how far away I can talk with my boys…and was a dramatic improvement from bubble pack gmrs/frs… but not best for SOTA (-:
Interesting on FT5D battery, and I bought an extra after seeing how quickly the FT3D went through battery… realized it was mostly having GPS on and APRS, and in past have turned them off. Would like to use APRS more in the future, (-: 73

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Before I starting activating CW, I carried a Mobilink TNC with me to do APRS on the FT270 (No FT3D at the time). Little thing worked surprisingly well. Integrates perfectly into APRSDroid. Sending APRS messages was just like texting someone.

These days I just let RBN take care of everything if I don’t have service. :slight_smile:

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We were trying for a S2S with another activator about 42mi away as the crow files. Full quieting to us but she was not hearing us. I rotated the Arrow 3-element and she got us 59 when it was rotated to about 70 degrees from vertical. We may have been bouncing off another mountain causing the polarization to be wonky. VHF can be fickle.

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It’s hard to be sure, but polarisation does twist with reflections, even when there do not seem to be many reflective points on the path or near it. For some reason polarisation does not seem to shift so much when using horizontal.

Having the feedline run down between the elements is another way to spoil the radiation pattern of a yagi. The feedline needs to go out at right angles to the plane of the elements, or back along the boom and only go down when it’s a quarter wave or more away from the nearest element.

73 Andrew VK1DA/VK2DA

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