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g7afm
Intermediate Member
Joined: Wed Jan 08, 2014 7:37 pm Posts: 63 Location: Herefordshire, wab so63
Feedback: 1 (100%)
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 2 METRE INTERFERENCE
Hi all just got back on 2 metres suffering with interference on ssb in the evenings when my next door neighbour gets on the childrens band anyone got any details for building a high pass filter or any links to purchase said item. Thanks Phil G7AFM
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Wed May 25, 2016 11:10 am |
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G0BHD
Contributor 2020
Joined: Sat May 23, 2009 1:46 pm Posts: 22851 Location: Shropshire UK IO82TN
Feedback: 6 (100%)
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 Re: 2 METRE INTERFERENCE
g7afm wrote: Hi all just got back on 2 metres suffering with interference on ssb in the evenings when my next door neighbour gets on the childrens band anyone got any details for building a high pass filter or any links to purchase said item. Thanks Phil G7AFM Strange to get interference from 27 Mhz I assume? Whats he running? Its an odd harmonic for dirty/harmonic interference from 27 Mhz operation, (5th and a bit), is he running some very dirty linear? I had a neighbor quite some time back, who ran very high power on 27 Mhz, he was well into his freebanding whilst I was involved with amateur radio, and 2 meters was never interfered with. (Other bands were from time to time). What 2 meter radio are you using?
_________________ Dave G0BHD. Been there and got the T shirt, sadly like the T shirt the memory of it has long since faded, gone rather tatty, and finally been consigned to the bin!
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Wed May 25, 2016 12:18 pm |
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G4LNA
Contributor 2020
Joined: Sat Mar 31, 2012 8:11 pm Posts: 3631 Location: Markyate, St Albans, IO91ST
Feedback: 8 (100%)
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 Re: 2 METRE INTERFERENCE
How much power is he running? Even running 400W on 10Mtrs would not affect operation on 2M, it sounds like he's got some seriously illegal stuff running there. I don't think a filter will help.
_________________
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Wed May 25, 2016 12:18 pm |
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g7afm
Intermediate Member
Joined: Wed Jan 08, 2014 7:37 pm Posts: 63 Location: Herefordshire, wab so63
Feedback: 1 (100%)
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 Re: 2 METRE INTERFERENCE
Thanks for the reply i know he has a linear not sure what reckons he doesn't use it very often the radio is a superstar 6900,says he is running about 30w even though the max should be 4 as far as I know but he is using some sort of echo/power mike i get about S8 of hash from him between 144,260 up to 144,350 my radio is the ft897d.
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Wed May 25, 2016 12:26 pm |
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G4LNA
Contributor 2020
Joined: Sat Mar 31, 2012 8:11 pm Posts: 3631 Location: Markyate, St Albans, IO91ST
Feedback: 8 (100%)
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 Re: 2 METRE INTERFERENCE
I don't think there's anything wrong with your radio, what you have described is a spurious emission from his rig, possibly the fifth harmonic.
_________________
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Wed May 25, 2016 12:40 pm |
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G0BHD
Contributor 2020
Joined: Sat May 23, 2009 1:46 pm Posts: 22851 Location: Shropshire UK IO82TN
Feedback: 6 (100%)
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 Re: 2 METRE INTERFERENCE
g7afm wrote: Thanks for the reply i know he has a linear not sure what reckons he doesn't use it very often the radio is a superstar 6900,says he is running about 30w even though the max should be 4 as far as I know but he is using some sort of echo/power mike i get about S8 of hash from him between 144,260 up to 144,350 my radio is the ft897d. I suspect he uses the linear, overdriven to death, far more than he lets on! The 897 can suffer beakthrough on 2 meters, as can the 857, I had an 857 for a few months on loan, it got clobbered by local paging, (no longer on air thankfully), whereas my trusty old FT221R, didn't suffer a bleep from it! A filter might help, designs out there are numerous, like this one: http://yu1lm.qrpradio.com/2m%20BP%20FILTER-YU1LM.pdfChoice of suitable rated components for amount of RF power you intend to run is critical of course. There are many other designs around, and some commercial ready made ones of course if you search online. Like these: http://www.dci.ca/?Section=Products&SubSection=AmateurGood quality off the shelf ones are not that cheap though! To be honest as he pushes the bounds of legality with his standard rig power, (4 watts AM/FM 12 watts SSB on the legal sections), let alone the "occasional" addition of a linear, and you are a licensed compliant HAM, I personally think he should clean up HIS act, rather than you be saddled with cleaning up HIS mess! 
_________________ Dave G0BHD. Been there and got the T shirt, sadly like the T shirt the memory of it has long since faded, gone rather tatty, and finally been consigned to the bin!
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Wed May 25, 2016 12:41 pm |
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g7afm
Intermediate Member
Joined: Wed Jan 08, 2014 7:37 pm Posts: 63 Location: Herefordshire, wab so63
Feedback: 1 (100%)
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 Re: 2 METRE INTERFERENCE
Thanks Guys Unfortunately not in the best of locations for VHF as surrounded by hills on 3 sides within about a mile radius so will probably do more portable work on 2 will have another word in his ear (with a bloody big bat if need be) fortunately he,s only on in the evening so the w/ends are quite (at the moment )
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Wed May 25, 2016 1:00 pm |
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M0VMT
BANNED
Joined: Wed Aug 14, 2013 8:29 pm Posts: 10538
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 Re: 2 METRE INTERFERENCE
Blow his front end off 
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Wed May 25, 2016 2:23 pm |
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G4LNA
Contributor 2020
Joined: Sat Mar 31, 2012 8:11 pm Posts: 3631 Location: Markyate, St Albans, IO91ST
Feedback: 8 (100%)
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 Re: 2 METRE INTERFERENCE
M0VMT wrote: Blow his front end off  Wouldn't take much, 400W on 10M should do it nicely. I don't know much about CB rigs, but my guess is the front ends are pretty naf.
_________________
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Wed May 25, 2016 3:16 pm |
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G7LAS
Advanced Member
Joined: Mon Apr 11, 2011 8:40 pm Posts: 104 Location: Swadlincote, South Derbyshire IO92fs
Feedback: 14 (100%)
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 Re: 2 METRE INTERFERENCE
Are you SURE it's his 11m radio and not something else?
In my experience the biggest interference to 2m are phone chargers. Rob G7LAS
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Fri Jun 03, 2016 8:03 pm |
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g7afm
Intermediate Member
Joined: Wed Jan 08, 2014 7:37 pm Posts: 63 Location: Herefordshire, wab so63
Feedback: 1 (100%)
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 Re: 2 METRE INTERFERENCE
G7LAS wrote: Are you SURE it's his 11m radio and not something else?
In my experience the biggest interference to 2m are phone chargers. Rob G7LAS Deffo from his 11m radio the only time I get it is when he transmits.
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Sun Jun 05, 2016 12:21 pm |
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M0RDI
Contributor 2020
Joined: Tue Nov 19, 2013 10:05 am Posts: 2480 Location: Banbury Oxfordshire
Feedback: 15 (100%)
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 Re: 2 METRE INTERFERENCE
 Are you afraid of him ??? Just ask him politely to turn his amp off because it causes interference to 2 metres . If he does not comply you know what to do  edit I really should read all the posts . If you have already spoken to /reasoned with him and he carries on regardless well........what other option is there?
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Sun Jun 05, 2016 1:04 pm |
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g7afm
Intermediate Member
Joined: Wed Jan 08, 2014 7:37 pm Posts: 63 Location: Herefordshire, wab so63
Feedback: 1 (100%)
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 Re: 2 METRE INTERFERENCE
M0RDI wrote: :scratch: Are you afraid of him ??? Just ask him politely to turn his amp off because it causes interference to 2 metres . If he does not comply you know what to do  edit I really should read all the posts . If you have already spoken to /reasoned with him and he carries on regardless well........what other option is there? As said this location not great for VHF so not to bothered but if somebody had a link for a reasonable cheap high pass filter it might have been worth just trying it.
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Sun Jun 05, 2016 6:52 pm |
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M0VMT
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Joined: Wed Aug 14, 2013 8:29 pm Posts: 10538
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 Re: 2 METRE INTERFERENCE
Go to the ofcom website and fill out the correct form and have him answer to them. Mark
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Sun Jun 05, 2016 9:29 pm |
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G4WIM
Moderator
Joined: Sat Nov 03, 2012 10:21 pm Posts: 624 Location: Freckleton, Lancs IO83NS
Feedback: 21 (100%)
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 Re: 2 METRE INTERFERENCE
If he's interfering with 144MHz due to an unstable amplifier you might like to point out to him that he's also likely interfering with other more important services (ambulance / police etc) and it'd be a good idea to either get it fixed or stop using it.
FYI I had a similar problem here some time back with a CB'r using an illegal and very dirty 'linear' - I pointed out to him the spurious and how on my spectrum analyzer I could see it causing problems to other users.
Only tracked him down because I heard him say qsy to S18 on two metres at which point he found me waiting for him :-)
_________________ G8GIW licensed in 1972 (C&G RAE), then G4WIM in 1984 (12 wpm CW test), then KT6UK in 2000 (USA Extra Class), now safely back in the UK and retired early (Google bought the company I was working for !)
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Tue Jun 07, 2016 2:00 pm |
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