I’m a fan of the 6m band. It fascinates and frustrates me in equal measures, which is part of its appeal. It’s unpredictable, you can be working local stations within 50km of your QTH for some time and then all of a sudden a Portugese station will call you and they’re 59+40dB drowning out anything local. Sporadic E openings are a lot of fun on the band and it supports other propagation forms like TEP and even F2 at the peak of the sunspot cycle (not this one!).
I only operate on 6m when I’m out portable and I have two antennas, both of which I feel are suitable for portable use. My 6m operating is mostly a mix of SOTA activations and contesting, although I did go out for one or two of the SpE openings after work on a summers evening.
I have the SOTABeams SB6 Beam and the 6m 5ele Tonna 220505 Yagi options for my 6m portable operations and am pleased with both of them, however in terms of performance there’s not too much to pick between them. This is surprising given the SB6 Beam is essentially a 2 element Moxon, while the Tonna 220505 is a 5 element monster Yagi and much, much bigger!
Surprisingly the 5ele Tonna Yagi has less gain than the SB6 beam. I suspect the SB6 beam is broader, but it is also much smaller and lighter! The only trouble I have (being in IO91) is that I’m surrounded by QRO contesters and it’s harder to null them out with the SB6 than the Tonna.
I’ve been very impressed by the performance of the SB6 6m antenna. I’ve used it in numerous contests and on SOTA activations this year and it’s a tough one to beat for portable use.
Side by Side Specs
Here’s how the two antennas compare, these are taken from the published specs and also include some of my (subjective) opinions based on personal experience:
|SOTABeams SB6||Tonna 220505 5ele Yagi|
|Cost||£59.95 (from SOTABeams)||£89.95 (from Martin Lynch & Sons)|
|Front to Back ratio (calculated)||24.6dB||23.8dB|
|Power rating||150W||500W (never used more than 10w myself!)|
|Overall Length||2m (width), 0.5m (depth)||3.4m (long)|
|Time to Erect||~2 minutes||~10-15 minutes|
|“Erectability”||8/10 – Very easy to keep up in the air using a lightweight fibreglass fishing pole. It does catch the wind a bit, but this is pretty much unavoidable with any 6m antenna, bar a vertical.||5/10 – Quite difficult. This is a lot of metal to hold up in the air on a windy hill top! I use an aluminium mast guyed at two separate points, using 6 guying ropes in total. This certainly needs more engineering if it’s to stay in the air.|
|Strength||5/10 – Quite fragile (made from fibreglass), the feed point broke off on the first use due to it hitting the ground. It’s not rock solid by design and this is how it achieves its light weight nature.||9/10 – Not fragile (made from aluminium).|
|Directionality||6/10 – Quite directional. You can easily peak signals by turning it slightly, although it feels quite broad. This is no bad thing sometimes, as your signal will gain wider coverage, perfect for SOTA but not ideal for contest DX or to null out local QRO stations.||8/10 – Good directionality. Despite the similar (predicted) radiation patterns this antenna does feel more directional. I feel like I can pull out weaker DX stations than I can with the SB6 and the beam is a bit narrower. This is all subjective of course!|
|Visual Impact||8/10 – Pretty low visual impact for a 6m antenna! I feel more comfortable using this one in public locations. An added bonus is that you can paint the white fibreglass poles to make it blend in a bit – sky blue or battleship grey?!||4/10 – There’s no hiding this antenna, people see it from miles away and it certainly gets some looks. I wouldn’t feel comfortable using it on any busy public hilltops. Perfect for UKAC use in the dark though 🙂|
Using the SOTABeams SB6 During the RSGB 6m AFS
Another bonus of the SOTABeams SB6 is that you can quite easily make a 2m version with just 5 spare fibreglass rods, some wire and two plastic separators. SOTABeams do offer a 2m version (SOTABeams SB2), but I wanted to make it myself. You could also quite easily make a 4m and even a 70cms version, but for 70cms I’d prefer a few more elements.
You can probably guess that I’m quite fond of the SOTABeams SB6, I still find it amazing that such a small and simple antenna can punch well above its weight and compete with a 5 element Yagi, I’ve still not got my head around this!
If I want to enter a contest seriously I’ll still reach for the Tonna, as I feel the directionality is better on this, but for everything else I’ll pack the SOTABeams SB6 without thinking.
For my operating needs the SOTABeams SB6 clinches the deal and if I could only have one it would be this!
Have you used anything else for portable 6m operation? Leave a comment below!