In reply to G8JSM:
I’d dispute GW/NW-044 as being a problem hill.
GM/SS-056 Green Lowther 5x16GW erp 24cms ATC Radar, GB3LA 2m repeater.
Andy
MM0FMF
In reply to G8JSM:
Hi Colin
G/CE-003 Bredon Hill can be added to the list.
Jonathan
M6HBS
In reply to G8JSM:
Presumably this depends on the mode used! I was up Cryn y Brain last year on 2m FM and suffered badly! Geoff 2E0BTR was on 2m SSB had no probs at all!
My advice use an 817 and the superior mode SSB!!!
My 2 pennies
Matt G8XYJ
In reply to MM0FMF:
I was bound to get some wrong!!, I can see that this is going to be interesting, getting consensus of what constitutes interference, and how severe, this obviously depends on the equipment, but at least the list could be used to make people aware of possible problems
Colin
In reply to G8XYJ:
There’s no way this wouldn’t garner comments as well as summits. So, Colin, if you keep the list at the top of thread updated we can all gibber away at the bottom and thus the number of birds killed per stone will be greater than one!
My Icom IC80AD is overloaded by the users own brain waves never mind external RF! 
It’s terribly sensitive to overload on 2m with an external antenna. I’ve used that on Feol Fenli/Moel Famau without a trace of interference this year. There’s a lot of gear up Cyrn-y-Brain and the last time I was there (2010) there were times when the IC80 noise floor was raised but not enough to limit comms. So if this problem is common on Cyrn-y-Brain then there’s something new at the site since Autumn 2010.
Maybe we should include the radio and antenna in use when suggesting problem summits? Just so we can gauge how bad the problem is likely to be. e.g. “Trio 2300 + internal whip was unusable” would imply nothing would work there. “Baofeng UV-3 + SOTA beam” suggests that most receivers would be usable 
Just a thought.
Andy
MM0FMF
In reply to G8JSM:
Gm/ns-151 mount eagle. Strong interference on 2m fm with my vx170, ok with the 817 on fm, both usIng sotabeam 3 ele yagi
Adrian
In reply to MM0FMF:
Well someone had to open the can of worms didn’t they!.
My thoughts, if you are going to make the effort to get to the top of a hill you would want the best aerial that you could carry, then sort out the rest.
I don’t mind trying to keep the list updated, but what is the best way to keep the columns separated, the formatting changes when I submit the text.
Colin
In reply to G8JSM:
Just a suggestion, Colin: when the list gets mature put it in the files section of the SOTA group.
73
Brian G8ADD
In reply to G8ADD:
Hi Brian,
Sounds like a good plan. I was trying to use OpenOffice spreadsheet so that I could sort into some kind of order, but the reflector doesn’t seem to support the formatting so I’ll have to do it the hard way!
Colin
In reply to G8JSM:
Colin,
For 2m FM with a VX-7 and dipole I think we need to add GW/MW-026 Long Mountain Beacon Ring and GW/SW-033 Wentwood.
Rod
In reply to M0JLA:
For 2m FM with a VX-8 and dipole, you can also add G/SP-013 Gun.
73 Mike
2E0YYY
In reply to 2E0YYY:
…and my house too 
You can add:
GW/NW-070 Great Orme
G/SP-015 The Cloud (problems from Sutton Common mast opposite experienced on wideband HH - VX7)
But…
With the “right” rig/aerial combo, you could find yourself with problems on many hills. And with the right rig/aerial combo, you can eliminate problems on most hills.
Tom M1EYP
In reply to M1EYP:
I agree, the point is to know which hills have a problem before you travel a couple of hundred miles to activate them
Colin
Colin,
G/CE-001 Cleeve Hill only needs to be on the list once !
Stewart G0LGS
In reply to G0LGS:
Didn’t have a problem up there with my old Kenwood TR-2600 on a whip antenna… Not the same for multiband HTs though.
73 Graham G4FUJ
I think that this has been running long enough to get most of the problem summits.I am not sure of the best place to put the list, or how to keep it current,possibly with more information on what rigs/aerials work where. All of the reports seem to be interference to fm handies with wideband receive, how many ssb handies are there?
The majority of these hills score only one point (17 one point, 4 two point and 1 four point).They are the kind of hills that a newcomer might try to see if Sota is for them, they are also suitable for a quick lightweight activation using a handie provided that the interference can be dealt with. At this point I would reccomend that you read the article that Rod M0JLA contributed to Sota News,An Anti-pager Filter for 2m Handys. These things work, I use one on Billinge Hill .I don’t think they will deal with kilowatts of radar interference or a local 2 metre repeater, but they certainly improve the situation regarding pagers.
I think that this will have been a worthwhile excercise if;
a) more filters are built.
b) the list is updated occasionally and it is easily accessible.
c) equipment for other bands as well as 2 metres is taken up these hills.
d) it alleviates the frustration of all of the chasers that are calling because the 2 metre equipment will be chosen/modified to work on the summit.
Any comments
Colin
G8JSM
In reply to G8JSM:
Colin
Surely the best place to put this sort of information is on the summits pages? They are likely to be the first port of call for most activators. A list on the reflector will soon be forgotten.
73
Richard
G3CWI
In reply to G3CWI:
Richard,
I think that is a good idea; a list will disappear and/or not be found when needed. Notes on the summit page are there to read when looking up other summit details. Perhaps a compact note on this info could be incorporated into the body of the summit entry.
e.g. “Pager makes 2mFM difficult with multi-band handys.”
I think that phrase sums up much of the info that Colin has collected here. Suitable versions would be needed for the ones with radar problems.
73,
Rod
In reply to M0JLA:
Hi Rod,
I agree, the summit pages are definitely the best place for this sort of information. I note that the summit page for G/SP-017 Billinge Hill already has a few items mentioning this.
I may add my short video showing the problem I had using a VX7-R on a short helical. I never intended using this for the activation & only switched it on to see how bad things were up there…I was not disappointed Hi!
My FT817ND however, had no problems on at all on 145MHz FM, using a vertical J-Pole.
73,
Mark G0VOF