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QRO (Heavy) vs QRP (Light) SSB/FM

This was asked on the FB group and I thought created an interesting conversation and curious some thoughts on here. Please keep in mind I am strictly an SSB/FM operator and looking at things from this perspective.

“Wondering if any experienced SOTA activators may own both an FT-817/818 and FT-891/857 and opt for the slightly heavier 857/891 option more-often-than-not? , Interested in thoughts behind the decision and lessons learned…(things beyond “more power is better during a sunspot low” and “you will need a bigger battery”; wondering about things an inexperienced / new activator might not think of relative to operations, other equipment choices, etc.)”

I use both an FT817ND and an FT857D. The only lesson that I learned for using the 857 and bigger battery was that I had to be less casual about how the rucksack was set up. With the greater weight the length of the shoulder straps and the waist belt needed to be just right, or you were feeling it by the end of the day!


@N4HNH and @W4KWM use an FT891 along with a BioEnno 6Ah battery. IIRC, they can get about 100 SSB QSOs at 45w using that setup.

I went with an FT818 and had good results with a SOTAbeams 20/30/40 linked dipole. I once had 80+ Qs from a summit in North Georgia on 40m, some as far as AZ. Didn’t have enough daylight to run 20m. :frowning:

I’m now running CW with an MTR3b and EFHW. Last weekend I rucked up the FT818 and all needed equipment and my legs/back could definitely tell a difference!


My experience tells me an “817” and a small PA is a better bet than an “857” type of setup. Most of the time you don’t need the extra power so you don’t need to carry the weight of a PA and bigger battery. You get to choose whether to take the weight penalty for a signal improvement. But if you buy a heavier radio then you always have the weight penalty even when 5W would do just peachy. Never mind the weight of a bigger battery.

So for me, a small PA and extra battery to add to an “817” system makes sense.

However, if you can be bothered you can get the equivalent of running 80W of SSB from your “817” setup for no extra weight penalty in radio or battery. It just requires some will power.


I never had success with SSB for SOTA, when I used QRP. I just met another activator during recent SOTA activation - K6EYE, who uses only phone modes (FM, SSB) for his activation. He also did not have any success with QRP SSB on HF.

With FM I can see that this is difficult in some areas. But SSB on HF bands too?

Are you selfspotting? That’s usually is the key to success with QRP.
QRP is perfectly fine. Just some days ago worked ZL from central Europe with 5 Watt ( about 18000 km - can’t go much further hi ).

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Probably using an EFHW then.



Hello AJ, as you mention FM, I assume some of your operating is VHF / UHF.
For these frequencies I tend to use the 817 and make up for lack of power by using aerials with some gain (multi-element Yagi). For the type of SOTA summits I work in the UK this seems to me the best option. Sorry, I can’t advise on HF.

This though obviously true becomes less convenient if you are going to use both HF and VHF, plus the extra cabling is something more to lose or have go wrong, besides adding somewhat to the set-up and breakdown time.

What is an EHFW?

EFHW - EndFedHalfWave antenna

And these EFHW antenna work perfectly well for me. I’m using a Xiegu G90, so this is not strictly QRP anymore, but I manage to reach much of Europe. I’ve even had recently two S2S from Switzerland to upstate NY and to QC.

73 de Martin / HB9GVW

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Always with the negative waves Moriarty, always with the negative waves.

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As far as I can tell, QRP 5W on HF SSB is good enough to guarantee successful activations, asuming you get spotted on SOTAwatch and you use frequencies not above MUF.
Not too long ago I had a great run of 79 QSOs in 50 minutes working 40m SSB with 5 watts from my FT-817ND into a 14m long endfed wire (not even a resonant haft wave length for that band)
If you want to go QRO, you’ll surely have bigger and longer pileups, so you should be prepared for that in terms of operating skills, resilience and battery charge, but that will be a personal choice, not a must definitely, because SSB on QRP has several times proved itself to be more than enough.
Whatever you finally choose, enjoy and have fun!



I found that on SSB a linear to get to about 30w made a big difference with only marginal extra weight. (Ft 817 set to 2.5W into a Chinese MX-50 Amp, usually on 80/60/40). ( I am usually time limited on the summit so speed for me is quite important )
Hopefully when we are further into cycle 25 the linear can go and the wavelength can get shorter! Am rather hoping to activate again in Cycle 25…I hope we are not measuring lockdowns in solar cycles… 73

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And Andy called ME negative!

40 m SSB QRP will work if you have a lot of local stations. This is applicable for Europe. It may not be a case in US.

What’s your idea of “local”?
On 40m SSB and QRP, you can be heard and chased at about noon by “local” stations in an area defined by a ring with inner radius of about 300 Km and outer radius of as far as 1500 Km…



Reasons I stay with my KX3 or FT 817 and sold my FT857.
FT 857 is 3kg and the battery I had to run it is 1kg before you put anything else in your back pack. RX for low down signals on CW is crap in spite of the alleged filtering in them. I gave up the idea 7 years ago, and I did not really yield any more QSO or Chasers by having extra power. I run my KX3 at 8 watts to a link dipole and it works fine. FT 817 comes with me on some hikes usually just to give it a run and it works fine as well and receives better than the FT 857. IMHO. Alert Spot Band choice Best antenna you can muster and willing Chasers are the key to success, RF power is way down my list.
vk5cz …

Newer ham and SOTA operator (licensed September). Besides the HT, the only radio I own is the KX2 (10w). I’m on a commercial EFHW multiband. If I do my part and put out alerts/spots that are accurate, there is usually a line of people waiting for me to call. Part of the challenge and reward of SOTA is making QRP work in austere conditions.

It’s not a fitness contest to see who can carry 50lbs of electronics to the highest elevation.