Of my approximately 290 activations in 5 years, I have only run 100W a couple of times - once from JW last year and once in connection with the LA SOTA meetup a week ago. These activations gave me the inspiration to make a serious attempt to put together something I could use. I pulled out a Pelicase copy I had lying around and took the spare home rig, the Icom IC-7000, which was only used for 2m/70cm. I had a separation cable for the front panel, and with Velcro this can be attached to the lid of the box during activation. I bought a LiFePO4 with 12.8V/7.8Ah/99.84W that I could fit in the box. The box weighs a total of 5.2kg This is 2kg more than my “Elecraft KX3 Retrofit V2” from RadioSet-Go
The first test was at Bjørnberget where I got a great result of 53 QSOs. I have never apart from JW had more QSOs on one activation. It was on this activation that one of the chasers used the term SOTA-QRO, a term I had not heard before and find very amusing.
The results are directly comparable with previous activations, as I used the same antenna as during the last 150 or so activations, the DXpeak vertical antenna
This is such a big difference between 5-10W and 100W that I will probably use the IC-7000 for activations, e.g. where it is less than 2 hours walk to the summit
Some of the readers will probably wonder why I use such a heavy box to keep the equipment in. The reason for this is primarily to protect expensive equipment from external influences such as impact damage and water/snow. Quite often I hike in hilly terrain where there are no trails or ski tracks. Throughout my activations, I have occasionally fallen, but no equipment has broken.
I used IC7000 and 10Ah LiFePO4 for couple activations during sun minimum. I found it good but too heavy for my old knees, especially on desent. I was even chased by couple DX stations (Japan, Indonesia and US) on SSB
Nowdays, if there is SOTA DX event going on I take MX-P50M and mcHF QRP. With the same battery I can operate much longer and save about 1.5kg in weigth. I find that with current propagation 50W is more than enougth for SOTA DX.
Thank you for sharing your experience of turning down the power and still being able to run DX, I will try that. My knees are not as they were either , but I always use walking poles and find that it is a good help for me.
Knut, you can use suitable camera bag for you equipment instead of heavy case. It gives adequate protection against the shock, as for waterproofing the backpack usually copes well with it.
I use the Yaesu FT 857D and made a case with PVC pipes.
It weighs much less than your Pelican.
Regarding the antenna, I believe you improve performance more if you use a Linked Dipole or EFHW.
Watch a video showing the manufacturing of the case.
You now have the dilema I have experience for the past few years, QRO and small summits or QRP and large summits. A healthy mix is good I think whilst the back to take it!
IIRC the most QSOs I’ve managed on a SOTA summit is 173 using an FT857 and SotaBeams Band Hopper IV linked dipole.
Dilemma, ORO vs QRP you are absolutely right
I often carry SotaBeams Bandhopper 4 as a spare antenna, and for use with “local” contacts at 80 metres. It is a very good antenna, but the disadvantage is that it takes a long time to set it up and change the band. This can be particularly challenging in bad weather, especially in winter in Norway,
I believe 100w is not necessary.
I make a lot of contacts with Europe and the USA with 40 watts.
the 857 consumes 14ah. The battery doesn’t last long.
Carlos
100W is nice to have, I am enjoying a lot portable DXing a lot and usually run 50W with 857. But quite often only switching to 100W gives me the chance to accomplish QSO. Especially if I chase someone on the west coast NA. Otherwise vertical with elevated radials brings a lot of QSOs even with bare KX3, especially on 15m
I’ve been considering a portable station with enhanced watts. My current rig is the IC-705, which I run barefoot and use for both SOTA and POTA activations. I recently activated a park in California on 20m and 40m and had huge success. That activation reminded me and encouraged me to stay on the simplistic course. I seldom make over 50 contacts spanning NY to Hawaii like I did that rare afternoon at Park K-0812, but I usually achieve enough contacts to score the activation officially.
I have several antennas I use for my activations. For the rugged 8-10 SOTA pointers, I usually carry my ID-52 along with my Arrow Yagi. For those peaks requiring less strenuous summits, six and below, I haul my IC-705 up the mountains. I get the best signal reports using my 705 coupled with my three-band SotaBeams inverted-V dipole configuration. But occasionally, I will also drag my MP1 Super Antenna with me.
Does anyone have advice about ideal conditions for the vertical (low angle) antenna vs. the dipole? Can anyone advise me on a good portable and lightweight 50-100w amp for my IC-705?
I asked my good LA SOTA friends which amplifier I should buy for my KX-3: They said it would be cheaper to buy a used 100 W (e.g. HF mobile station) and weight-wise about the same instead of the KX3 and an external amplifier. Since I already had the Icom IC-7000 I am using this. Is this something you should consider?
That’s a valid point. I am so happy with he quality of the KX2 and IC705 and enjoy their utility, I struggle to compromise on the rig. But I should look into it.
(tr)uSDX (5W) with endfed, coax, two ~15m ropes, throw-weight → packs very tightly and can be carried along in office backpack (for the “just in case” activations, similar to "Just in case" pays off, but not such splendid views mostly)
My experience is that the <5W with the (tr)uSDX are mostly comparable to the 20W G90 activations. When I struggle, I think that it is mostly due (a) activating after work late in the afternoon or (b) suboptimal conditions as I am more limited in placing the antenna or (c) the (tr)uSDX struggles with SWR (wet foliage?). But I may be lucky with having so many chasers eager to catch me or lucky being in easy reach for many chasers in Central Europe.
But maybe I have just been riding the lucky waves of the sun.
@HB9GVW quote=“LA9DSA, post:12, topic:33418”]
cheaper to buy a used 100 W
[/quote] @LA9DSA
Maybe but the KX3 is a better rig than the Yaesu 891, 857D etc.
Consider this kit if you are comfortable with a soldering iron. I have one, works great.
I use an RM Italy HLA-150V amplifier paired with the IC-705. They are fairly lightweight and it realistically provides about 80 watts. I use 4.2 AH 4-cell LifePo4 batteries, or on occassion a 22AH Ultramax ‘carry handle’ battery which seems to be easier to carry in the hand than it would be in a rucksack.
Having said that a lighter weight option would be an MX50 or equivalent 25-50w amplifier, mine puts out 25 watts. It makes more sense when teamed up with the FT-817 and 5w than the IC-705 with external power and 10 watts in terms of gain.
It’s good to have options - I’ve found this out over the years that having separate QRP rigs and amplifier, and small and large batteries, means you can custom fit the RF gear to match the activation.
When it comes to vertical antennas I’m still a bit clueless. I’ve taken a Super Antenna to Lanzarote and had 5w contacts with Australia. I think short verticals require better band conditions than inverted-v dipoles. The signal is stronger and more consistent in terms of QSB with the inverted-V compared to a vertical, although the Super Antenna doesn’t suffer from losses compared to my Chameleon MPAS 2 vertical - but, the Chameleon excels as a multi-band antenna - a simple band change on the rig is all that is required to transmit between 6m and 60m. It is my go-to chasing antenna, and also excels as a S2S antenna, whereas both the Super Antenna and Inverted-V require faffing with every band change.
Totally agree with this perspective especially when viewed over an entire sun cycle and different conditions. Which reminds me…I need to find my AlexLoop…perfect for 10m, 12m, etc
, but I always use walking poles and find that it is a good help for me.