Around here “local” is mostly just California which from my QTH is
as far as 500 miles away. A lot of the summits are too close for
40, too far for VHF. We have to go to 60 meters to be able to hear the QRP
activators, and I’m not sure I’ve ever worked an activator on 60M SSB.
73,
John K6YK
I’m just surprised that there aren’t more people keen to use the 80W PA for their 5-10W rig that doesn’t weigh much at all or need special batteries.
Gidday mate, which specific amp are you referring to here?
He’s referring rather obliquely to the gain in signal acquired by learning and using CW as opposed to SSB.
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Thanks for the translation mate much obliged! 
Guys, a little interjection wearing my moderator hat.
AJ2I asked a question. He was [quote=“AJ2I, post:1, topic:24716”]
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
[/quote]
Virtually all the answers fall into either the category of “I’m happy with my QRP rig”, “use QRP + amplifier” or “forget SSB/FM and use CW”. This may be intended to be helpful but it is not germane to the actual question and as such is a waste of electrons!
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I do and also have a (more recently acquired) KX3. I use the KX3 instead of the ft-817 - at least partly because it will do 15W rather than the 5W from the 817.
I used to carry the 857 on almost all activations until the KX3 arrived - and on quite a few while the KX3 had the original 10W limit.
The ft-857 comes out from time to time if there is a short, easy walk and I have a reason for wanting the 40+W then available.
My progression was from VX-3 to VX-7 (both 2m FM and with proper aerials) to ft-817 to ft-857 (initially 2m ssb as well as 2m FM and then, via 70cm FM to HF). The VX-7s are still in use and Vicki, M6BWA/P, has activated 500 uniques using hers. This has worked well for us both - in the UK. Things will be different elsewhere.
73
Rod
I made MG just using an 817 and a linked dipole on HF (with a few 2m SSB contacts thrown in for fun)
Good Brian! Your post was like fresh air! The moderator hat really fits you!
I have an FT-857 and an FT-817. I have had S2S with Australia from the UK using the FT-857. I have had contact with a New Zealand base station using the FT-857. I don’t think either of these would have been likely with the FT-817. Recently I have been chased from the US and Canada using the FT-817 on 5w.
In the winter I only consider the FT-817, due to total pack weight including winter clothing and equipment. Now that I’m a bit older and have aches and pains in my back I think twice about taking heavy equipment full stop. The better propagation due to the new solar cycle is negating the requirement for 100w for the most part. I still really enjoy QRP.
I don’t take an amp with me when operating the FT-817, but for a long time I took a little Chinese Amp giving me 25 watts. This combination is significantly lighter than an FT-857, but with extra punch compared to a barefoot 5w FT-817. You’ll probably get more contacts. It is widely believed that around 30 watts is the best power/weight compromise, after that as you increase power the weight requirements don’t justify the benefits to your signal.
So I turn it back to you. What kind of results would you like? If you are after DX from a summit then 100w will help. If you really enjoy a pile up that is possible with QRO or QRP. I will often take the FT-857 when chasing SOTA, because it increases my chance of breaking a pile up or making a contact with an activator.
From an inexperience point of view, things to consider:
- loads of folk will recommend QRP and a resonant antenna as an alternative to QRO.
- QRO rigs tend to be more fussy with power, which means SLABs or LifePo4s. Buck converters and LiPos won’t handle the power requirements.
- If you go QRO what will you have to leave behind to keep your pack weight sensible. I like taking the JetBoil and having brews on summits (and a bacon sarnie on the last outing).
- Get both rigs and see what works for you.
Most of it boils down to what floats your boat.
Hope that helps, Mark.
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I’ll just add another point that maybe isn’t obvious to beginners.
A QRO rig like the FT-891 or FT-857 will draw significantly more power than a QRP rig like the FT-817 when running at low power, due to the biasing current required on the bigger finals.
This is why, for example, the FT-817 and Chinese Amplifier will run for much longer at 25 watts than an FT-857 would, and why it would make no sense taking an FT-857 and running it at 10 watts either, as the current draw might be 10x that of an FT-817 on 5 watts.
So there is a lot of sense in taking ‘just enough power’.
Mark. M0NOM
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One usefull feature of the 857 is its notch filter, invaluable for dealing with the antisocial lids that tune up on frequency! I could do with something like that on my 817.
Hi
QRO or QRP depends on the difficulty of the references you want to make. If you want to make beautiful walks, more difficult, where weight counts, use qrp, if you want to make easy sotas use qro. In both ways with the tools that are available with the good hunters we have, it is easy to validate the references.
Gomes CT1HIX
QRO versus QRP
Hi AJ,
Since 2002 I have used a variety of equipment from FM hand-helds running 500mW to QRO HF kit. For WAB portable in days gone by, almost all of us used QRO.
It’s important to note that a 100W HF radio such as my IC706-2G, used on countless SOTA summits, (and the FT857) needs an increasing amount of input current per Watt output as you go down the scale. The highest power may only be needed for (part of) one QSO in ten but 100W out needs 20 amps in. (In reality with battery Voltages below the optimal 13.8V it might only take 16 amps and give out say 70W). From tests, it takes approx 5 to 8 Amps to produce 2 to 10W and in the order of 11 to 13 Amps to produce 40 to 50W from a 100W capable HF rig.
I used to run about 40W which I think is about the best compromise between consumption and the power required to ‘get on with’ the activation without too many repeats being required in mediocre conditions. (I think Dave G0EVV uses similar.) I need full output on 160m in daylight.
On the other hand I have also had some amazing successes with an FT817ND barefoot. When conditions are good it’s surprising what 5W can do and that’s down to the difference between QRO and QRP in terms of dB and ‘S’ Points at the chaser end. It’s common knowledge that in theory reducing 80W down to 5W results in an S9 in the chaser receiver dropping to S7 so there’s not much need for QRO in good condx.
Summit time can be similar with QRP and QRO. QRO will be heard by more chasers but hopefully you’ll need fewer repeat overs even in QSB. Despite more repeats with QRP, you can be on your way quicker provided conditions are reasonable since you won’t work as many chasers. If conditions are bad you still have the option to log a handful and go.
QRO means your battery needs to be at least twice or three times as big or more if you’re doing multiple summits or plan for a longer summit time/ more bands etc. In 2004 to 2008 I was doing several summits in a day with QRO and lead-acids so I know how backbreaking it can be.
Another thing is perception of pack weight. I find anything up to about 7kg is barely even noticed but 10kg is twice as heavy and 13kg is twice as heavy again! Multi-band overnight stays are the worst at 20kg plus. Unless it’s an easy summit, QRO will make you sweat more meaning more discomfort for the activation, significant in winter. You may opt for an extra layer to combat that. You will need extra food in winter and extra fluids in summer, which adds still further weight.
As mentioned by Andy if you go for a 5W rig and an amp you have more versatility as you can leave the amp in the car for one or more summits. I find that my FT817ND plus MX-P50M sucks in significantly less current than my 100W rig for the typical power I use – 30W (2.5W from the 817) or 50W (5W from the 817). This combination weights about 2kg with its interconnect cables (without batteries) whereas my IC706-2G weighs 2.5kg including wiring and that’s after I spent almost 40 hours hand-crafting a honeycomb epoxy case for it years ago.
On balance, I think QRP is likely to be the best choice for SOTA, particularly if you use CW and stick to bands like 40m or 20m (or higher in sunspot high). When conditions are not so good or if you want to mitigate against possible poor conditions when you get there or do specialist bands such as 160m, QRO has a role.
There are some good points in the thread and holes can be picked in some of what I have written here. There are many different approaches, experiences and ways of looking at things. That’s just mine but I think weight is up there with weather conditions when it comes to activating SOTA. A handie with slim Jim is like another World. I love it more and more now I’m getting on a bit!
HNY to all,
John
(G4YSS/ GX0OOO/P)
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I’ll tell you my story.
I started with QRP (FT818) short after getting my license (most of my radio activity is portable). After a first success. I struggled on a few activations… I could barely make the 4 contacts (20m and 40m) after spotting and had to search and pounce. And then on one activation, that didn’t even work and only made 1 contact. I decided to get an amplifier.
Fast forward a few months. I got the well known MX-P50M amplifier. All my activations became very successful. Of course I thought it was entirely due to the amplifier.
Fast forward another few months… I struggled and even failed on a few early morning or late afternoon/evening activations, with the amplifier: indeed 40m can be totally dead or unusable in the evening, especially in the summer due to QRN, and there are less active chasers some parts of the day (it seems chasers are still in bed before 8am 
)
Then I looked back at my failed activations without an amp… and guess what, they were in the late afternoon or evening, and in the summer. That was it… my failures in the early days of my SOTA adventures were probably caused by lack of experience and lack of understanding of propagation (not even being able to feel the band conditions), and not because of running QRP vs QRO.
The bottom line is that the level of experience of the operator is a key element to be successful at QRP. I had heard this many times (“QRP is not for new hams”) but did not want to believe this and didn’t understand it anyway. Now I do
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Hi Romain,
Yes band conditions are far more important a factor in success than, antenna, rig, power - almost anything. I’ve had some terrible times with 100W and barely made any contacts. On the other hand I’ve worked people with QRP on HF then noticed the mast had fallen down and the dipole was on the ground!
There’s no substitute for good condx.
John
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Sorry to get on the CW kick earlier, but seriously if you are going to
work SSB, more power is better! Sounds like the little amp is the
better deal.
73
John, K6YK
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Better than ? and what for?
That’s what I’m missing in your statement, John.
QRO is heavier in terms of transceiver and battery. Is that better?
QRP is lighter and enough to enjoy good pileups on HF surely qualifying the activations. Is this better or worst?
To me, QRP is better for SOTA activating because it’s magic that 5W from a summit let’s us contact friends at the other side of the planet.
73,
Guru
The increase in tranmitted power between 40w and 5 watts is a ratio of 8 and that translates into a fraction over 9 decibels. (10 log power ratio).
Because voice waveforms are not constant, and have an average power down in the 20% area, ssb is at a disadvantage to CW mode just in terms of output power. This can partly be fixed by adding a compressor such as the one sold by sotabeams and others. This device, when adjusted correctly, increases the average power of the ssb transmitted, without significantly degrading the quality of the transmission. Estimates vary but some say the improvement is equivalent to adding the 9db of the amplifier option. I certainly notice increased performance from my 817 when using the compressor.
When using the MXP50M amplifier, care is needed to avoid overdriving it, as overdrive results in a wide transmitted signal and does not improve the on-channel intelligibility. The power meter may rise but the perceived signal on frequency does not. Maybe most of the extra power is in the spurious signals on either side… with my amplifier, 40w is output with 2.5w input from the 817, 20w from 1w drive and 10w with 0.5w the lowest setting on the 817.
Having said all that, I have run activations where all contacts were made at the lowest setting of the 817, half a watt. I didn’t work any dx that day, but then, in VK many of the contacts are out at 1000km and are taken as normal, whereas in other places that would be a contact with another country and qualifying as “DX”. Eg. Canberra to Melbourne is only 450 km, but Canberra to Adelaide or Brisbane is around 1000 and Perth vk6 takes it out to over 2000km. Canberra to ZL3 is similar. These contacts are routine when using a 10w kx3 or 5w 817 and an efficient antenna.
A lot of results depend on selecting the right time of day, efficient antennas and choosing a good frequency, combined with spots on sotawatch. I really like the post above from @SP6SUD. Spot on…
Making contacts on HF is not like working through repeaters on VHF FM, or making phone calls. There are additional factors and only experience will allow the operator to learn how to use them to best effect.
73 Andrew VK1DA/VK2UH
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