Mount Roosevelt Activation 2015

Great Day today!!!

Also a quick video!!

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Sorry we didn’t manage to make it on 28mhz yesterday, I heard you in and out and you came back a few times asking for the portable station, but my 3db less than you was just too much.

I was on GM/SS-154 and round to the south east side of the hill and slightly down (hiding from the wind) so the antenna was a bit shielded in your direction.

I guess the S2S in GM you got was Steve gm1ink ?


Yep, Steve had a great signal.

How was I sounding on your end. I was getting some amazing reports out of Austria and Germany.

sadly quite weak with me, as I was with you. my aerial was shielded in your direction by the hill I was on. I use 10m of wire up a pole and an ATU and I think it may be worth trying a dipole to see if that works better.

1/4 Wave, Low angle-5 pieces of wire on a SO239 C, Easy for 10m. And maybe a small amplifier and you will have fun !


For 10m, I’d even recommend a 5/8 wave, which is something manageable and gives you about 3dB of gain and a lower radiation angle conpared to a 1/4 wave.
However, using a vertical gives you equal chances to work anywhere in the world but makes you waste power when you want to focus on a specific direction.
An interesting directional array is a center fed vertical dipole on a fishing pole and a vertical reflector at the right distance behind.
Or even an inverted V dipole on a pole and an inverted V reflector behind on another pole.
Or a moxon rectangle held in place with the help of a couple fishing poles…
Many options.
Best 73 de Guru - EA2IF

ahh that small amplifier. It has a “small battery” to power it? :smile:

Ahh, it’s true, many options - I think I have enough things to try to keep me busy for a while!


Isn’t that called a Moxon in the vertical plane :smile: Tried that, good idea but difficult to set up in anything but a marginal wind. Yes a 5/8 would be better, but then you need to match a high Z to 50R, where as with the 1/4 Lambda your pretty close.

Not as much power as you think; its surprising a 50W PA will last a long time on a 7 Ah Battery. A number of us do this. I am actually building a 150W version that I have used in my PicASTAR to go portable with - soon to be fully licensed call, but then again big batteries don’t really cause me an issue.


Once I started using this inverted V antenna I haven’t looked back. Easy to carry, easy to set up, and running 10 watts SSB I seem to get some pretty good signal reports. I really enjoy hitting the stations in the UK and Europe. What an awesome hobby!

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Which design did you use? (or a design you think is good at the moment)
Any recommendations for a 50W (around that) PA for HF? I’d like to pair it with Softrock.


If you want to Homebrew one, I suggest you look at G6ALU’s pages. Softrock - the “pennywhistle” pinched his design basically.

W6JL has developed a good 50W final amp, using inexpensive IRFZ24N’s which are about 60p each. I have used the same finals in my Portable Minima HB transceiver with a different OP topology producing very good results. I will draw and publish the schematic if your interested.

You will also need to build a suitable LPF - Low Pass Filter network. Depending on your skills you may choose to design one in a CAD tool such as AADE filter design, or use LTSpice to simulate them, which I am doing at this very moment as it happens ! Alternatively there are plenty of designs on the web.

Have fun homebrewing !


Yes Im looking to homebrew things even if I fail in the beginning :smile:

Regarding design, simulation and optimisation, Im not at that level at the moment but I could build an existing design.
I could even simplify the network is I build it only the the softrock’s bands.

Design that I can source the component in the UK easily would be great! Im interested in your design for sure. We could chat off reflector if you like.