Thanks Gavin, I have looked at this presentation before, will review again.
Mark.
Off topic I know but found GM3SEKs video very useful to help get rid of noise. https://www.youtube.com/watch?v=LSL1h6MJbaI Where I live it is more rural and we do have full fibre so no nasty VDSL but with anywhere between 2 and 4 teenagers and their devices getting the noise level down was problematic. When we had building work done I installed cat 5 around the house - so we currently have 3 APās. (The walls are rather thick and the house spreads over three floors). Anyway after much faffing around when everyone else was out turning everything off one of the main culprits was the power supplies for the ap / router and the worst was the psu for the Openreach fibre modem, and the cat 5 cables were acting as antennas fed against the ground. The solution was twofold, firstly plenty of turns around a good ferrite core between the PSU and the routers ( So it is the same rubbish Openreach power supply with about 20 turns around a good ferrite before it is plugged into the modem ) AND the shack filtering unit described by GM3SEK. The only time I have a problem now is when Northern power grid have a problem with their network as their HT line is close to the property - it got really noisy (S9+ 50Hz noise across everything) - then all the lights went out in the village and they repaired an underground cable and now it is quiet again!
Would be interested in an amplifier but I think it probably wouldnāt be very sensible with my semi-stealth antenna arrangements I donāt want to end up setting the wood alightā¦ 73 Paul
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Iām actually watching it now Paul, thanks, Iāve watched it before but a while ago. Cheers, Mark.
PS ā¦ I must read all the replies before responding! One other thing that was noisy was my Windows PC (Generic) which leaked RF out of everywhere, USB, Sound Card, Ethernet, Com Ports for CAT control. When I retired after spending 20+ years getting frustrated with Windows I went Mac and assumed I would be met with the same problems. My Mac mini however seems radio wise silent and has needed no filtering. Iām not sure what your DEC machines emit? (LW QRM?). The Cat 5 cables really confused me as the noise seemed to be coming from everywhere - and of course it was! The only way I managed to get rid of most of the noise was to turn everything off, run the radio off a battery and turn things back on one at a time. A few USB adapters then mysteriously disappeared and it appears that not all makes of LED bulbs are equal. Good luck with your noise hunt. The downside of having a low noise floor when working non-sota stations is that I can hear much more that I can be heard as most people seem to have a few more s points of noise.
PPS Extreme solution - we rented Honeypot cottage in Upper Teesdale when doing building work. It is shown on the photo here ( the first house ). The nearest neighbour was about 500m away!
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I know youāve considered this option but my experience was, for me, an IC-7300 was the answer. I started with an IC-705 for activating and also used it in the shack but found this frustrating. Buying the 7300 made a big difference. This wonāt apply to everyone but a factor for me is a generally poor QTH with a very small garden where I just have room for a small doublet antenna with an automatic ATU at the base of the mast. Transmission performance is fine but reception performance could be better. The result is with āonlyā 100W if I can hear a SOTA activator they should be able to hear me. If I had 400W (legal limit. 
) I might be heard further away but I suspect I wouldnāt hear a QRP station at that distance.
Of course, if you have the room for a better antenna the distant QRP stations will be heard and more power might be appropriate.
The menu system on the 7300 is more less identical to the 705 so the learning curve will be easy. Unlike the Yaesu FT-897D Iāve just bought (for the 50W multi-mode VHF) which has a menu system from another planet!
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Thanks John, I know this would make a lot of sense. When I helped with the Barrow SOS station I was able to navigate their IC-7300 with ease, I was really surprised as at the time I was clueless as the simularity.
Cheers, Mark.
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Is there a greater risk from spurious signals when amplifying qrp radios that much, compared to a QRO radio amplified by less to produce the same no of watts?
i.e. do qrp rigs supress spurious signals by the same dB relative to intended signal as a high power rig (which would be good), or just keep them below a specific dBm? In the latter case more spurious will presumably result from this configuration.
As a QRP activator Iām all for anyone chasing if you run your legal limit off your 100ā tower or qrp from a wire in your tree call me thats what Iām out for. I chase Sota from my shack with 100 watts from my Icom 7300 into my dx commander ABV. If I can hear the station I normally can work them , If I had an amplifier I probably would only use it to break through DX pile ups not Sota though thats just my personal preference for myself chasing, 100 watts normally does the trick for me.
73 de VE6JTW, Jesse
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This cannot be answered in general terms. There are QRP devices that produce a very clean signal and cause less interference with the PA than with a less good 100 watt device, but there are also QRP and 100 watt devices that should not be used with an amplifier. The reviews in the magazines provide information on this.
73, Peter - HB9PJT
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Just as an update - I built a GM3SEK mains filtering unit and have installed FAIR-RITE 0431177081 chokes on the HF coax feed into the antenna tuning unit and the back of the FTDX-5000MP (new shack rig!). I also have a choke to install as close to the EFLW matching unit as possible, but the WX hasnāt been agreeable. I have some smaller chokes installed on leads that connect directly to the rig, and the mains cords are looped through some Mix 31 ferrite rings.
I have had some RF issues in the shack, but they have been limited to a touch LED lamp I use to illumate the rig (installed right next to it) and a weird light thing the missus has in the bedroom - which is directly under the rig - and cost about Ā£6 and is as cheap and nasty as it gets.
I fixed the LED touch lamp from having issues by wrapping the base in copper tape except the touch controls. The weird LED light is still RF sensitive and shows Alex when Iām making a contact (itās an RF sensitive āON AIRā light). Wrapping it in copper tape would somewhat defeat itsā purposeā¦
My plan is still to connect all equipment chassis on the filtered side of the mains unit to a copper bar in star fashion then implement an RF ground using the technique mentioned in this article.
I have used RG58 on the counterpoise side of the MFJ artificial ground to run the counterpoise out of the shack - on the other side of the window I have an earth bar to which a couple of 1/4 length counterpoises are added (taking into account the RG58 length).
I have also read this article by Jim Brown K9YC - RFI-Ham.pdf which is very comprehensive. Iām still a little confused about some of the concepts, but I think my level of knowledge is better than it was.
The 200 watts of the FTDX-5000 definitely comes in handy at times, but Iām typically running 100 watts max on SSB and 30 on CW/Digital. It is amazing how you can lust after power, then as soon as you have some more you dial it back. The little power knob on this rig is very deceptive in what it controls.
Mark.
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Read up on PME and make sure you do the right thing if your house is wired for PME.
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Regarding the sub-topic of using QRO to chase summitsā¦ From the perspective of the north central US, I have been very pleased with the results of chasing with QRP (max of 5 watts). Besides being a committed (probably should be) QRP operator, that always seemed more āsportingā when the vast majority of the activators are QRP as well. But as they say, YMMV.
73,
Randy, ND0C
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Of course not. And - in my opinion - also absurd.
If I can hear an activator with the usual 10W, then I can also reach it with 10W.
And if not, what good will 1000W do for me? Except qrm and the usual stress in the pileup.
73 Chris
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Try chasing European and NA summit activations and resulting local pileups from a nice quiet location in ZL with 10w and youāll understand the desire for QRO. If bands are open I can copy them easily right down to S1, but breaking through the wall of local EU/NA stations to reply ā¦
So yes - I can chase EU / NA from ZL with QRP, but only if Iām the first or only station calling, or if the activator is kind enough to occasionally request QRP only or DX only (and chasers are kind enough to obey).
OK - a big directional antenna would also resolve this. But the impact on the local āoutstanding natural landscapeā would be problematic, more of an impact on others than simply upping the power.
So horses for courses, I say.
Matt - ZL4NVW
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This is as big a problem for those in the same continent! The best solution is to hang back and only call when the baying pack has moved off after other prey. This leaves one fewer in the mass of callers, which benefits the activator who also has to contend with that wall of sound.
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1000W gets the chaser heard above the rest of the pile up, worked quickly and so released to search for and work the next activator. Some people just have to be in front. 
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Clearly power levels are a very personal thing, and if it were possible to take 1KW on a mountain, someone would be doing it (and there would be lots of folk complaining about it).
Everyone seems to have their own version of how much power is acceptable, and when we are talking small numbers squaring power doesnāt seem that bad. So going from 5w to 25w is probably acceptable to the majority. However, going from 25w to 625w is suddenly a big deal.
No consideration of antennas here either. My EFLW is clearly not going to have the impact on a pileup that a 10 element log-periodic at 30m is going to have. So this is all very subjective. I could be transmitting 1KW into an effective dummy load and only causing problems for myself.
As far as Iām concerned if folk are using power within their license conditions and are operating in the spirit of amateur radio then Iām OK with that.
WRT the RF issues Iāve had, they happen on the lowest power setting of the rig. The issue isnāt high power it is very poor RF screening from cheap electrical gadgets.
Mark.
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I sometimes think about a linear to get to 400w, and then I usually realize that the wire antenna between trees in the wood would not be a sensible choice with more power, the ATU wouldnāt cope and probably the cost might not be appreciated by my XYLā¦ My next step might be a temporary Hexabeam
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As one who does almost entirely s2s, I canāt wait for a pile-up to clear. I have to be first in line so I can QSY to go after an in-state operator who will stay on 40m only briefly. Ironically, Iām the only one in SOTA history who has run a KW from a qualifying peak, apparently.
Elliott, K6EL
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You canāt just drop that in there Elliot without giving us a storyā¦?